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Emmonak-Alakanuk Wind Design and Construction Project 65% Design - Sep 2010 - REF Grant 2195468
Alaska Village Electric Cooperative Emmonak/Alakanuk Wind Design and Construction 65% Design Documents AEA Grant #: 2195468 September 24, 2010 Table of Contents Executive Summary……………………………………………………………………………………………………………… 1 Schedule and Budget Overview……………………………………………………………………………………………. 3 Electrical System Overview…………………………………………………………………………………………………… 6 Performance Modeling…………………………………………………………………………………………………………. 9 Civil Design……………………………………………………………………………………………………………………………. 12 Electrical Design……………………………………………………………………………………………………………………. 16 Mechanical Design………………………………………………………………………………………………………………… 23 Operations Planning……………………………………………………………………………………………………………… 24 List of Included Attachments………………………………………………………………………………………………… 26 Executive Summary The Emmonak/Alakanuk Wind Design and Construction project involves the construction of a four turbine (400 kW total generation capacity) wind power project and electrical intertie between the communities of Emmonak and Alakanuk. Activites are currently underway and the majority of project construction will be completed during 2011 and consists of three primary components: 1. Four Northwind 100 (100 kW) wind turbines 2. 10.5 mile electrical intertie between Emmonak and Alakanuk 3. New, automated switchgear, secondary load equipment and associated controls for the Emmonak power plant Construction of the project is scheduled to begin during the winter 2010-2011 season. Turbine installations and the intertie run will be completed during the winter/spring of 2011 and all integration activities are expected to be completed by early 2012. Construction activities will be completed by Alaska Village Electric Cooperative (AVEC) through existing construction management contracts and electrical integration activities will be completed by internal cooperative resources. Cost estimates have been outlined in the existing grant agreement between AVEC and the Alaska Energy Authority (AEA) and are summarized below: Total Wind Project Costs $ 4,200,000 Total Intertie Project Costs $ 3,200,000 Total Integration/Control Costs $ 1,488,000 Total Project Costs $ 8,888,000 The total project cost is inclusive of an $888,000 project match by AVEC and the $8,000,000 grant from the AEA. AVEC is currently engaged in efforts to expand the project (install more turbines) through the solicitation of additional, non-AEA funding. If successful, AVEC could expand the project from four up to ten turbines without the need to modify the current electrical integration strategy documented in this submission. Wind conditions at the project site have been estimated at 5.89 m/s (at 37 M hub height) through the combination of recorded MET tower data and correlation with long term recorded wind data from the community of Emmonak. The completed project is expected to run at a 23.4% capacity factor (100% availability) which will create a low penetration wind/diesel system once the project is fully complete. Average wind penetration level for the project is estimated to be 14.1% (100% turbine availability) based on a combined average load for the villages of Emmonak and Alakanuk at 687 kW. Combined, Emmonak and Alakanuk have a recorded minimum load of 380 kW and a peak load of 1,053 kW. The combined system of Emmonak and Alakanuk will become one of the largest, in terms of overall energy consumption, within AVEC’s network once completed. Through the 1 of 26 scope of work under this project, the installation is expected to displace approximately 55,664 gallons of diesel fuel annually. Completed geotechnical analysis indicates that the project site and route for interconnect transmission line lie within a discontinuous permafrost zone in generally silty soil conditions. Geotech analysis has not revealed any conditions that the project team is not intimately familiar with through the execution of similar scopes of work in similar locations across the Yukon Kuskokwim Delta. Foundation designs for the installed wind turbines have been designed with consideration of soil conditions at the project site and document an engineered pre-cast concrete solution supported by driven piles. AVEC has utilized the same foundation design at AVEC’s wind turbine installation in Quinhagak. Six thermo siphons will also be installed at the each foundation to preserve frozen ground and improve stability at the installation site which will be located on the North West corner of the village. Minor site access roads will be developed at the project site and along the transmission line route to support construction and future operation and maintenance requirements. All wind generated electricity from the project will be managed through Dispatch/Secondary Load Control equipment installed in the Emmonak powerhouse. Integration equipment installed as part of this project consists of automated switchgear, turbine dispatch/secondary load control, and resistive heat load equipment (electric water heater). AVEC will utilize a dump load water heater to control/monitor excess wind energy supplies which have been estimated to be minimal due to the relatively low penetration of the installed system. Heat generated from the excess energy will be utilized at the Emmonak powerhouse. If the system is expanded in the future, AVEC intends to further evaluate the necessity of additional load management equipment and will explore the potential of implementing dispatchable heating equipment in various locations in Emmonak and/or Alakanuk. Major equipment (wind turbines) is covered under a two year manufacturer warranty and AVEC will service the new generation equipment in accordance with established procedures for AVEC’s existing wind energy systems. The Emmonak / Alakanuk project will be the 10th wind-diesel installation the cooperative has undertaken. Installed equipment and operational procedures will be consistent with AVEC’s existing fleet-wide components and practices. 2 of 26 Schedule and Budget Overview Project activities for the Emmonak/Alakanuk Wind Design and Construction project are currently underway. As of September, 2010, the majority of project equipment, materials, and supplies has been procured and are in the process of transport to the project site. Construction of the project will begin during the winter 2010 season. Construction activities for the wind farm and intertie route are expected to be completed by spring 2011 and integration work is expected to be concluded by the end of 2011. A summarized project schedule indicating specific milestone activities is included at the end of this section. An updated version of the project master schedule is included as an attachment to this document. The total project costs for the wind power/intertie project are estimated to be $8,888,000 and the current project design of four turbines and the associated intertie has been budgeted for as follows: Total Wind Project Costs $ 4,200,000 Total Intertie Project Costs $ 3,200,000 Total Integration/Control Costs $ 1,488,000 Total Project Costs $ 8,888,000 Consistent with AVEC’s/AEA’s grant agreement, an updated project budget is included below: A TOTAL GRANT BUDGET BY TASK OR MILESTONE $ 180,000 $ 3,500,000 $ 5,158,889 $ 50,000 $ 8,888,889 BY BUDGET CATEGORIES $ 354,000 $ 55,000 $ 2,750,000 $ 159,000 $ 5,450,000 Materials & Supplies $ 54,000 $ 66,889 $ 8,888,889 BY FUND SOURCES $ 8,000,000 $ 888,889 $ 8,888,889 Milestone 3 TOTAL Grant Funds (90%) Grantee Match – Cash (10%) Construction Services Other Direct Costs Travel Contractual Services BUDGET SUMMARY Milestone 1 Milestone 2.1 (major procurements) Milestone 2.2 (remainder of Milestone 2) TOTAL TOTAL Direct Labor and Benefits Equipment 3 of 26 AVEC is also current engaged in efforts to solicit additional non-AEA funding to expand the scope of this project. If successful, AVEC intends to utilize the funding to install additional wind turbines during the current construction schedule. By capitalizing on equipment already on site, AVEC anticipates the ability to construct and integrate additional turbines to the project for an approximate incremental cost of $800,000 per turbine. 4 of 26 5 of 26 Electrical System Overview AVEC expects the installed Northwind 100 wind turbines to produce approximately 14% of the electricity consumed in both Emmonak and Alakanuk today (14% wind penetration level across the combined community load). The wind turbines should supply almost 845,600 kWh of electrical energy annually, including a minimal amount for use to heat water. Should the project scope be expanded through the installation of additional wind turbines, AVEC believes an additional 6 Northwind 100 wind turbines could be installed without significant changes to the current integration and load management strategy. Electricity generated from the installed turbines will be consumed in both villages through the completed 10 mile electrical intertie. The wind turbines will interconnect with the existing diesel power plant in Emmonak. Secondary load control will dispatch the installed water heater as required to use excess wind energy while allowing the diesel generators to continue running at efficient/programmed levels. The wind-generated electrical energy will be delivered using a slightly extended electrical distribution grid also included as part of this project. The goal of this project is to reduce the cost of energy within the two communities and this will be accomplished through the displacement of diesel generation fuel and the reduction of O/M expenses in Alakanuk. Once this project is completed, the current diesel generation facility in Alakanuk will be converted to stand-by status and primary electricity will supplied form the installed wind turbines and diesel generation facility in Emmonak. The conversion of the Alakanuk is not included under the scope of work for this project. AVEC is seeking non-AEA funding for the completion of this work. Constraints Electricity generated from the project is subjected to the constraints of physical abilities to transmit the energy to where it is needed when it is produced (or stored for a use at a later date) and the total energy demands across the connected communities. Due to the installation of appropriate transmission equipment and the relatively low penetration level of the installed system, neither constraint is expected present challenges to the completed project. Wind Resource Documentation Wind data recorded at the project site from an installed MET tower has been collected over a 16 month period and utilized in the analysis attached to this submission. Detailed information regarding the wind resource is included in the attached “Emmonak, Alaska Wind Power Report.” Report submitted and accepted by the Alaska Energy Authority in August, 2010 (Milestone 1 submission). Wind resource data is included with the electronic attachments (HOMER file - Emmo and Alakanuk, AWOS adjust.hmr). Annual Electric Load Data To evaluate a combined Emmonak and Alakanuk load profile, generation data was combined for the two communities and synthesized using the Alaska village load calculator spreadsheet developed by the AEA. 6 of 26 The results were then adjusted slightly to match actual data recorded in the communities of Emmonak and Alakanuk documented by AVEC in the cooperative’s annual power generation report. The result is a virtual Emmonak-Alakanuk village with a 687 kW average load, 1053 kW peak load, and 380 kW minimum load. Seasonal, daily and DMap profiles of the Emmonak-Alakanuk virtual load can be found in the attached Emmonak, Alaska Wind Power Report. AVEC is currently in the process of installing digital data loggers at all of their generation facilities across the cooperative’s network. Data loggers have been in place in Emmonak since July, 2009 and in Alakanuk since July, 2010. Data captured through these devices is recorded at 15 minute resolution and is included with this report as an electronic attachment. Load Projection The communities of Emmonak and Alakanuk have experienced steady growth in monthly kWh consumption that is consistent with AVEC’s system wide averages. Consumption/Generation in Emmonak has increased by approximately 16% since 1992 (.86% annual average) while consumption/generation in Alakanuk has increased 54% (2.42% annual average) over the same period. It is expected that the combined load for both villages will continue to grow throughout the duration of the project’s lifespan at a rate that is comparable to AVEC system wide averages. Over the same period (1992-2009), consumption has grown by 27% (1.36% annual average) across AVEC’s entire network. Information involving trends regarding average monthly consumption for the communities of Emmonak and Alakanuk can be found in the charts below. 382 393 387 367 382 388 396 403 408 397 392 399 413 399 420 425 422 446 317 326 336 335 344 352 362 376 380 390 393 399 397 390 392 390 396 404 200 250 300 350 400 450 500 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 Alaska Village Electric Cooperative Average Monthly kWhr Consumption for Residential Class Emmonak Village Average Monthly Residential kWhr Consumption System-wide Average Monthly Residential kWhr Consumption 7 of 26 276 278 282 264 296 345 362 380 372 389 407 426 431 399 389 394 416 425 317 326 336 335 344 352 362 376 380 390 393 399 397 390 392 390 396 404 200 250 300 350 400 450 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 Alaska Village Electric Cooperative Average Monthly kWhr Consumption for Residential Class Alakanuk Village Average Monthly Residential kWhr Consumption System-wide Average Monthly Residential kWhr Consumption 8 of 26 Performance Modeling Operational Modeling The relatively low penetration level of the completed wind-diesel system (estimated at 14.1% wind penetration – 100% turbine availability) in comparison to existing AVEC managed wind-diesel systems will result in little excess wind generated energy. Nonetheless, and due to existing AVEC established operating procedures, there will be periods when the amount of wind generated electricity on the combined Emmonak / Alakanuk system exceeds current demand and minimum diesel generation set- points. This excess energy will be managed through the use of secondary load controlling equipment. Excess energy will be utilized at the Emmonak powerhouse through an installed dump load water heater that is connected into existing heat loops within the facility. Due to the relatively low heat contributions, excess energy supplies have not been factored into economic modeling (HOMER analysis anticipates no contributions to heat through excess wind generated electricity). Anticipated wind production also correlates well to periods of high demand within the communities. This also contributes to a more stable electrical system. More information about anticipated monthly energy contributions from generation resources in the community can be found in the attached Emmonak, Alaska Wind Power Report. A summary chart of expected wind penetration on the combined system can be found below: 9 of 26 Updated Economic Modeling In August, 2010, the Alaska Energy Authority completed a revised economic analysis for the purpose of evaluating this project. A summary of AEA’s analysis is included below: Results NPV Benefits $5,550,034 NPV Capital Costs $8,383,720 B/C Ratio 0.66 NPV Net Benefit ($2,589,501) The AEA analysis was based on the following assumptions: Performance Unit Value Displaced Electricity kWh per year 676,480 Displaced Electricity total lifetime kWh 13,529,600 Displaced Petroleum Fuel gallons per year 48,794 Displaced Petroleum Fuel total lifetime gallons 975,885 Displaced Natural Gas mmBtu per year - Displaced Natural Gas total lifetime mmBtu - Avoided CO2 tonnes per year 495 Avoided CO2 total lifetime tonnes 9,908 Proposed System Unit Value Capital Costs $ $ 8,888,889 Project Start year 2011 Project Life years 20 Displaced Electric kWh per year 676,480 Displaced Heat gallons displaced per year Displaced Transportation gallons displaced per year Renewable Generation O&M $ per kWh $ 0.007 Base System Unit Value Diesel Generator O&M $ per kWh $ 0.020 Diesel Generation Efficiency kWh per gallon 13.86 Parameters Unit Value Heating Fuel Premium $ per gallon $ 1.00 Transportation Fuel Premium $ per gallon $ 1.00 Discount Rate % per year 3% Crude Oil $ per barrel $ 110.00 Natural Gas $ per mmBtu EIA As part of this design document, an additional cash flow/cost-benefit analysis based on separate assumptions has also been created. Summary info on this analysis is below: 10 of 26 Project Returns NPV INVEST NPV BENEFITS Cumulative Benefit Discount Rate 3%($1,270,123)$9,603,227 12,632,816$ 4%($1,932,172)$8,583,420 5%($2,494,590)$7,715,933 Benefit/Cost Ratio 6%($2,973,370)$6,974,188 1.42 7%($3,381,701)$6,336,711 8%($3,730,498)$5,786,086 Payback (Years) Project IRR 1.45% 18.86 The summary above was generated though the assumptions included below. An electronic copy of this model and the one generated and accepted by AEA is included as an electronic attachment. Direct Labor and Benefits 354,000$ Travel 55,000$ Equipment $2,750,000 Materials & Supplies 54,000$ Contractural Services 159,000$ Construction Service s 5,450,000$ Other Direct Costs 66,889$ Total Project Costs 8,888,889$ Include Energy Sales in Cash Flows ("Y"=Yes; "N"=No)Y Current Enegy Sales Price (EMO - $/kWh) 0.303$ Assumed Price Reduction from Wind 15% Post Wind Install Energy Sales Price ($/kWh) 0.25738 Estimated Project Life (Years- Enter either "20" or "25") 25 Installed Turbines 4 Fixed Annual Project O/M Costs (% of Total Project Cost) 0.50% Variable Annual Project O/M Costs ($/Generated kWh) 0.00975$ Estimated Diesel Cost ($/gal) 2.8072$ Estimated Annual Diesel Cost Inflation (%) 2.15% Estimated Value of Green Tag Sales ($/kWh) 0.005$ Estimated Annual Value of Alakanuk Plant Decommissioning 170,000$ Expected Annual Gross Energy Generation (Total Project - kWh) 845,600 Estimated Wind Project Loss Factor (%) 17% Estimated Annual Net Generation (Total Project - kWh) 701,848 Estimated Efficiency of Existing Diesel Plant (kWh/Gal) 12.94 11 of 26 Civil Design AVEC has spent significant resources evaluating two specific project sites in Emmonak to hold the installed wind turbine generators. Determinations about the final civil designs for the project have been based on the following course of project related events: May, 2007: MET Tower installed in EMK November, 2008: Grant Submitted $10.7 million requested for a 800 kW, 8 turbine project with interconnect line between EMO/AUK $4M per village cap was adopted after submission of application Project recommended an $8 million award with a match of $890k February, 2009: Site control obtained for two potential wind farm project sites, each with room for six turbines March, 2009 - Round 2 Funding Recommendations Announced by AEA August, 2009 - Legislature approves $25 million in spending to support some of the recommended project Program shorted $25 million for the funding year April, 2009: Project size reduced from 8 turbines to 5 based on project analysis and funding limitations Changes made based on a proposed total budget of $8.89M and new intertie route September, 2009: Recon completed of intertie route between EMO/AUK. Tie line routing scouted by helicopter by DMA/Golder and STG. Activities funded by the Denali Commission. Winter 2009-2010: Extensive geotech completed through three field studies/drilling. Activities funded by the Denali Commission. Drilling/geotech completed behind EMO power house Drilling/geotech completed along intertie route Drilling/geotech completed at both potential wind farm sites February, 2010: Intertie route finalized March, 2010: Site visits to EMO by AVEC Managers to coordinate project activities and obtain site control. April, 2010: AVEC and STG meet with AEA staff 12 of 26 Meeting to identify necessary steps to get a grant agreement in place Changes in the grant administrative process also discussed May, 2010: AVEC and STG meet with AEA staff Meeting to discuss a revised scope necessary to evaluate the project and determine if a grant agreement can be issued for the project May, 2010: Site visits to EMO by AVEC Managers to coordinate project activities and obtain site control. May, 2010: Intertie design completed May, 2010: Site plans completed for wind farm sites June, 2010: Updated wind study incorporating long term AWOS and localized MET data completed. June, 2010: Site visits to EMO by AVEC Managers to coordinate project activities and obtain site control. June, 2010: Revised Scope Submitted by AVEC and accepted by AEA June, 2010: Easements obtained for intertie route July, 2010: Resolutions and letters of support from local government and air carriers obtained to support FAA permitting efforts July, 2010: Grant Issued by AEA and delivered to AVEC for signature (not executed) July, 2010: Detailed cost proposal produced by STG and based on revised/reduced design delivered to AVEC Proposal provide more detailed project costing and complete bill of materials Included thermosyphons not included in original estimates Included additional pilling indicated through preliminary structural design Based on revised install locations identified through ongoing FAA permitting discussions Changes result in more civil work for roads pads, and distribution line extension Based on a revised intertie route covering 10 miles instead of 6.7 as originally proposed Changes aid constructability and consider appropriate/possible river crossings Changes required to avoid land ownership/allotment complications Changes reflect a tie with conductor size of 4/0 instead of 1/0 at 12.47/7.2 KV to limit line loss 13 of 26 Costs based on a completed intertie design July, 2010: FAA Determinations of No Hazard to Air Navigation (Permits) issued for six turbine locations located at site 2 wind farm August, 2010: Revised AEA grant issued to construct four turbine project with intertie between Emmonak and Alakanuk August, 2010: Structural foundation design completed August, 2010: Turbine supply contract executed, intertie materials, and wind turbine foundation components procured August/September, 2010: Project mobilization of all WTGs, Intertie materials, project supplies, and equipment sent to Emmonak through two barge shipments. AVEC intends to construct the four turbine project at the locations labeled “Option 2” in the attached site designs. Material procurement, project plans and construction plans have been based on the utilization of this location. FAA permits have also been obtained for construction at this site. Currently, AVEC is working with the FAA to obtain decelerations of no hazard for six additional turbine sites marked as Option 1 in the attached site plans. These sites would be potentially be utilized to site additional wind turbine generators in the future if declarations can be obtained and if AVEC is successful in obtaining additional funding to expand the project. AVEC currently has site control at both sites. Site plans for both locations are include as attachments to this document. Geotechnical Evaluation Emmonak lies within the Yukon River delta and is situated on the northern bank of Kwiguk Pass, a channel of the Yukon River, near its mouth at the Bering Sea about 120 air miles northwest of Bethel. Emmonak is located in the Yukon Delta National Wildlife Refuge. Pleistocene and Recent delta building has played a major role in shaping the regional geography and most near-surface deposits in the area are composed of fine-grained alluvial silts and sands. Coastal wave action has probably sorted some of these silty and sandy deposits and eolian silts are commonly intermingled with surface organic deposits. The area surrounding Emmonak has low relief, and is mostly flat to very slightly rolling. Peat and organic silt deposits have accumulated in poorly drained low-lying areas. Lacustrine silt may underlie existing ponds or other low areas. The Emmonak area has been mapped within the discontinuous permafrost zone. Permafrost is typically absent beneath large water bodies and adjacent to flowing streams and sloughs of the Yukon River. Near-surface permafrost may also be absent beneath low-lying wet areas. Permafrost typically underlies areas of relative higher elevation that are generally free of brushy vegetation. 14 of 26 A complete geotechnical report for the project is included as an attachment to this document. Foundation Design AVEC will utilize a foundation design that is almost identical to the design utilized for the cooperative’s wind installation in Quinhagak. The foundation design consists of a pre-cast concrete foundation supported by driven piles. A complete set of foundation drawings (95% level) is included as an attachment to this document. Electrical intertie Design During 2010, a complete intertie design was created to document routing and to determine an accurate take off list for materials. The completed intertie between Emmonak and Alakanuk will span a distance of approximately 10 miles. AVEC has obtained an easement for the power line routing and all required permitting is expected to be in place by November, 2010. A complete set of intertie drawings (95% level) is included as an attachment to this document. 15 of 26 Electrical Design The Emmonak project involves the installation of 4 Northwind 100B wind turbines (400 KW total generation capacity for the project), new automated switchgear, Secondary Load Controller (SLC), new secondary electric loads, and a wind dispatch control module. The installed turbines will be located on the western edge of the community of Emmonak, approximately 1 mile from AVEC’s existing power plant. The wind installation will be electrically connected into existing 3 Phase service and the energy produced from the system will be utilized in both Emmonak and Alakanuk through the installation of a 10.5 mile electrical intertie. Communications with the installed turbines will be managed through an installed wireless system that links the wind generators with new controls located in the Emmonak powerhouse. All integration activities associated with the wind installation will be completed in the Emmonak power house. Through a separately funded project, AVEC is in the process of redesigning the Emmonak power house and developing a new, stand-by generation facility in Alakanuk. Design efforts for these projects are in progress and will be accomplished with consideration of the upgrades and integration activities accomplished through the scope of work completed through this AEA funded project. Final design activities are in progress and AVEC anticipates having all aspects of the wind energy system commissioned and operational by the end of 2011. Remaining integration activities are being executed internally by AVEC Operations and Engineering staff and equipment suppliers (Northern Power). AVEC is currently designing a SLC module internally (AVEC has procured this equipment from outside vendors in the past). The project will utilize a Wind Turbine Dispatch Controller supplied by Northern Power until the new SLC is installed and commissioned in the Emmonak powerhouse. Similar to AVEC’s existing wind-diesel systems, the Emmonak installation will utilize a dump load water heater to manage excess wind energy supplies and maintain overall system stability. This equipment is consistent with the fleet components that are found throughout the cooperative’s network of wind-diesel systems. Additional dump load heating equipment will be considered as necessary as AVEC gains operational experience with the new system. Due to relatively low penetration levels of the new wind system, the completed project is expected to provide minor contributions towards heating loads. Almost all of the energy generated through the completed wind project can be utilized to offset diesel generated electricity. The major integration components of Emmonak’s wind-diesel system consist of (equipment to be installed through the scope of this project in italic): Four (4) Northwind 100B wind turbines Wireless communication system (for installed wind turbines) SmartView SCADA System Northern Power Wind Turbine Dispatch Controller (WTDC) AVEC Secondary Load Controller (SLC) Secondary Electric Load Equipment (dump load water heater) Kohler Automated Switchgear Four diesel-powered generator sets 505 kW 16 of 26 557 kW 337 kW 908 kW Kohler Supervisory Diesel Controller (PLC) Energy production estimates for the Emmonak wind system indicate that it should have an approximate 23% capacity factor which would result in average wind penetration level of 14% based on the combined reported average load of Emmonak/Alakanuk of 687 kW (2009 data). Even though a low penetration level has been projected, it is also expected that the penetration level of the completed wind system may result in operational situations when the energy output of the wind turbines exceeds the load in these villages. In situations when wind energy production exceeds current electricity demand within the community (along with total dump load capacity in the connected hot water heaters/heat loop) wind production is curtailed by shutting down wind turbines as necessary to maintain system stability. In Emmonak, it is expected that these procedures will need to be considered once the cooperative gains operational experience with this particular system. Decisions regarding the operation schedules for the Emmonak turbines along with the potential necessity for additional load management equipment will be made through operational experience after the system is fully functional. AVEC anticipates the completion of integration activities for the Emmonak project during 2011. One way AVEC has accommodated excess wind energy without shutting down wind turbines in the past has been accomplished through the utilization of a Secondary Load Controller (SLC). AVEC has utilized this equipment at Selawik, Kasigluk and Toksook Bay with SLC’s supplied by Sustainable Automation. This is currently being completed at Chevak, Hooper Bay, and Gambell with SLC’s supplied by Northern Power as well. Similar to AVEC’s wind-diesel system in Quinhagak, the cooperative will also utilize a SLC in Emmonak that is being designed, constructed, and installed through the AVEC’s internal Operations and Engineering departments in lieu of procuring a SLC supplied by an outside vendor as AVEC has done in the past. The existing SLC’s at Selawik, Kasigluk, and Toksook Bay, and soon to be installed SLC’s in Chevak, Hooper Bay, and Gambell, all energize and de-energize resistive elements in a conventional water heater. At Emmonak, AVEC has decided to utilize a single dump load hot water heater (and potentially incorporate resistive air heaters if deemed necessary through operational experience) as load management equipment. As excess wind energy enters the combined Emmonak/Alakanuk electrical system, resistive elements within the water heater are turned on/off to balance overall energy flows and system parameters. The overall system design is almost identical to the wind-diesel system being designed for Shaktoolik and contained identical components contained in projects across AVEC’s network (controls, switchgear, turbine dispatch/secondary load control, resistive load management equipment, etc.). Documentation of the specific integration components that will be installed under the scope of this project can be found as attachments to this submission. Minor modifications of these designs will potentially be implemented as final plans are executed. Primarily, the purpose of Emmonak’s SLC and resistive energy management equipment is to absorb excess energy generated by the wind turbines during periods of low village loads as well as to allow for maintaining some load on the diesels at all times. This will maintain overall system stability and reliability during periods of fluctuating wind. There is also an indication that through the extremely fast on/off switching of elements in the dump load hot water heater, the SLC will counter the rapid changes in the output of the wind turbines to improve overall power quality. It is expected that the AVEC designed SLC switching cabinet-dump load combinations will perform better than the systems previously supplied Sustainable Automation or Northern Power SLC switching cabinet-water heater combinations due to tighter and more integrated engineering elements. 17 of 26 Similar in design to the dump load water heaters that AVEC has utilized in the past, the installed dump load water heater in Emmonak is anticipated to have a total capacity of 260 kW including all resistive steps. During the fabrication of the new SLC, the final size of the individual resistance steps in the water heater will be documented. The water heater consists of “off the shelf” technology and will be manufactured by Caloritech. Water heated though this system will be connected into the existing heat recovery system within the Emmonak power plant and primarily utilized to offset the cooperative’s heating costs/operational cost at the facility. AVEC’s internally developed SLC is also being designed to incorporate the potential expansion of the project (additional turbines) and the future functionality of dispatchable tertiary electric heating loads located across the community. It is anticipated that these tertiary systems (either hydronic or forced air) would be installed in public facilities (Emmonak or Alakanuk school, city offices, village corporation) and be utilized to supplement existing diesel fired (heating oil) heating systems in these facilities. The applicability and/or necessity of tertiary load management equipment and controls will be determined by AVEC once operational history/data is obtained from the newly installed wind system. Nonetheless, all integration equipment associated with the installation in Emmonak will be limited initially to the power house until AVEC gathers some operational experience with the new system. Once all integration work at Emmonak is complete, wind generated electricity will be managed through the utilization of both the WTDC and the SLC. The primary function of the WTDC will be to turbines on and off based on the parameters and generation set points established by the overarching diesel control system (PLC) which monitors village load conditions and diesel generation. The supervisory controller also places generators on/off-line as required to meet system demands while sending appropriate signals to the WTDC about the ability to turn wind generators on and off. In Emmonak, as in all of AVEC’s automated village power systems, set points for individual generators are established in the PLC programming to regulate generator run times in order to: 1) Ensure that adequate generation capacity is on-line to meet current and anticipated system demands 2) Maximize diesel fuel efficiency 3) Provide individual generators within each village system relatively consistent run time 4) Maintain proper operation temperatures in the village power house Across AVEC’s network of isolated generation facilities, established generation set points vary widely depending on the make, model, and age of individual generators along with the overall system configuration in each village. Nonetheless, AVEC generally establishes set point parameters that allow individual generator sets to operate between 25% and 100% of their rated capacity. For example, in the case of a 200 kW diesel generator, an installed AVEC PLC would allow this particular generator to operate between 50 kW and 200 kW. Additionally, as a general operational rule, AVEC systems will not allow any generator to run below 50 kW of output at any given time, so the minimum set point of this particular set (or any generator below 200 kW max output) would be limited to 50 kW. AVEC’s general PLC programming guidelines will be followed in Emmonak which will essentially create three operational scenarios with the completed wind-diesel system: 1) Diesel Only Operation: When the wind turbines are offline, the generation system will function under normal demand control. When the system-wide demand exceeds 90% of the rated capacity generators currently on-line for more than 2 minutes, the PLC will automatically bring 18 of 26 an additional (the most appropriately sized) generator on-line. Once the second generator is brought on-line and if demand drops below 80% of the generation capacity of either individual generator for a period of more than 5 minutes, one of the generators will be taken off-line. 2) Low Penetration Wind-Diesel Operation (system load greater 2x total wind project output): When conditions are such that the combined wind energy output is less than twice the current total system demand, the power plant will function essentially as it does under diesel-only operation. In this mode, the PLC communicates with the WTDC to determine if/when turbines are allowed to run. Once this determination has been made, the installed SLC directs wind turbine energy supplies towards overall system demands (effectively reducing load on operating diesel generator sets) and/or diverts power to dump load heat elements as necessary to address quick shifts in power quality due to wind variations. This functionality provides overall system stability and keeps generators running within established parameters. 3) Medium/High Penetration Wind-Diesel Operation (system load is less than 2X total wind project output): When the conditions are such that the combined wind turbine output is providing more than half of the total system demand, the SLC will control resistive heating elements in the installed dump load elements to ensure that generators are run above their minimum operating capacity. Thus, the SLC functions as an active load management device by diverting wind generated electricity towards the fulfillment of general system demands and/or resistance heating elements as necessary to maintain proper load management, overall system stability, and optimum efficiencies. Should temperatures in the dump load water heater rise above acceptable levels, warm air is vented from the facility to ensure that adequate heat load capacity is available. Should diesel generation demands drop below minimum loading set points through the loss of the SLC (or inability of the SLC to send excess energy to resistive elements), the PLC signals the WTDC to shutdown turbines as necessary to maintain system stability. As necessary, the SLC also controls the air heaters to deliver heat sufficient enough to maintain adequate loading capacity on operating diesel-generators. It is anticipated that under this operational scenario, some level of wind generated electricity would be diverted to resistive elements at all times. AVEC also anticipates having the WTDC module installed and commissioned in the Emmonak plant prior to the installation of the SLC. During this interim (period between WTDC commissioning and SLC commissioning), AVEC will run installed turbines conservatively through the use of the WTDC to manage wind generated electricity supplies. Under this temporary operational scenario, varying set point parameters will be tested and established to prevent wind generated energy supplies from overpowering the electrical system. These parameters will essentially limit the project to low instantaneous penetration levels until the SLC is installed later this year. AVEC anticipates the SLC to be installed concurrently with the installation of new, automated switchgear at the facility. Communication Integration Plan Reliable communications is essential to the monitoring, control and trouble shooting of the wind system installed in Emmonak. Northern Power’s web based Smart View SCADA System is the medium for providing this necessary information and control of the Emmonak wind system. AVEC will install a wireless communication system between the four wind turbines and the Emmonak power plant to monitor energy production and system performance along with general turbine control. A decision was made to install a wireless system in lieu of the “hard wired” fiber optic cable system previously used at 19 of 26 AVEC’s existing installations at Toksook Bay, Kasigluk, Savoonga, Hooper Bay and Gambell. The wireless system will be identical to what is currently being deployed in Mekoryuk and Quinhagak and consists of standardized AVEC fleet components. Hardware for the communication system at Emmonak will consist of a L-Com Global Connectivity Hyperlink Wireless 900 MHZ Professional 8 dBi High Performance Omni Antenna Model HG908U-PRO at each wind turbine and at the power plant. This antenna is attached to a fiberglass support beam secured to the W36 main beam of each wind tower foundation with the top of the antenna 11’ 2- 5/32” above the top of the wind tower foundation and located to the right side of the steel service mast. AVEC Operations is expected to specify B & B Electronics LMR 400 cabling with an outside diameter of .405” and protected it with 2” liquid tight flex from the antenna to the spare conduit routed into the interior of the wind tower with the final designs. Inside the tower, AVEC Operations will utilize a new Hoffman cabinet mounted to the side of the Down Tower Junction Box. Included in this cabinet will be a 900 MHZ Wireless Ethernet Bridge. Both the bridge and the Ethernet switch utilize a 120 V power supply. Mounted in this cabinet as well will be hardware to record and communicate temperature readings from the thermoprobes installed in the turbine foundation. This information will be utilized to monitor operational conditions and as a basis to further study the structural requirements of turbine installations on top of permafrost conditions. AVEC anticipates utilizing this data in the future to further refine wind energy foundation design requirements. At the Emmonak power house, AVEC will utilize the same antenna. The antenna cable will then be routed to a Hergo Brand 24” x 14” x 18” Communications Cabinet located in the Butler building. This Communications Cabinet will house the proposed Ethernet Bridge and the proposed Ethernet switch and is also supplied with 120 V power. Through this system, communications between the installed turbines and the Emmonak power house will be managed through the utilization of Northern Power’s SmartView Monitoring System which provides a data logging and diagnostic interface required to provide remote support for the Northwind 100. The SmartView platform provides a user-friendly, real-time monitoring, control, and reporting platform. The SmartView platform allows access to turbine control features, and reporting for wind turbine owners, remote monitoring services from the Northern Power Network Operations Center (NOC). 20 of 26 Screen shot of AVECs Fleet wide SmartView Portal The SmartView platform is based on a web-based HMI, but is currently being retooled to operate on AVEC’s internal Intranet. Ultimately, AVEC will assume all monitoring responsibilities for their fleet of Northwind turbines, but will continue to utilize Northern Power’s monitoring services for the Emmonak installation throughout the turbine warranty period (two years post-commissioning). Up to this time, Northern Power will provide web-based access so the 24/7 staffed NOC based in Vermont can provide support and turbine monitoring services to make sure the fleet is up and running and producing power at its optimum output. This configuration ensures that when a fault does occur, the system can get back on-line with the least amount of downtime. It is anticipated that the project will be operational through the use of the WTDC prior to AVEC assuming full monitoring responsibilities. General SmartView Specifications: Form Browser based real time human-machine interface (HMI). Distribution Via the Internet or an organization’s Intranet, allowing authorized personnel access to the system. Access Available on the web for public viewing or can be configured to operate within a network’s firewall. Information Included: Energy production, wind speed, capacity factor, turbine availability, estimated cost savings, and historical data. 21 of 26 Once integration activities are completed and the SmartView system retooling is complete, AVEC will continue to utilize a modified version of the existing SmartView platform for system management and control. 22 of 26 Mechanical Design While the low penetration level of the completed wind installation in Emmonak is expected to provide minimal contributions of thermal energy, AVEC will install load management equipment to manage excess wind energy generated through the completed project. These particular integration components are included within the scope of this project to: Ensure a high level of system stability Fully utilize all wind generated energy Incorporate integration components that will allow for relatively seamless project expansion in the future Mechanical equipment installed through the scope of work in this project includes an electric dump load water heater and will be managed through the installed Secondary Load Controller and overarching power plant PLC. The installed water heater will be physically located in the Butler building and piped into an existing heat recovery system within the Emmonak power plant. An additional pump will be added during the installation of this equipment, but all other existing mechanical equipment will be unchanged. A mechanical drawing of the Emmonak power house that documents existing equipment, radiators, pumps, and controls is included as an attachment to this document. The existing heat recovery system at the Emmonak plant has an approximate total capacity of 400 gallons and is piped directly to existing generator sets to capture heat/facilitate cooling during the generation process. The installed heat recovery system is also connected to Emmonak’s water treatment facility which has the ability to accept heat generated from the power house as available. Generally, most all heat created/captured in the Emmonak plant is utilized within AVEC’s plant. Due to the relatively low expected thermal contributions of the installed wind system, it is also expected that operational procedures regarding heat utilization will remain unchanged once the completed wind project is operational. It is anticipated that the installed electric water heater will be sized at approximately 260 kW, well above any expected instantaneous power contributions from the installed wind system and comfortably within the overall mechanical system heat limitations. The water heater will be manufactured by Caloritech (CCI Thermal Technologies) with standard “off the shelf” technology that is consistent with existing fleet wide components utilized by the cooperative. Should the Emmonak wind farm be expanded at a later date (additional turbines installed), the mechanical infrastructure implemented through the scope of work under this project could support the additional energy contributions of these generators comfortably. Additionally, if the project is expanded, AVEC would also consider remotely installed (outside of the power house, but within the communities of Emmonak and/or Alakanuk) dispatchable mechanical controls that would provide thermal energy to public facilities. The potential addition of this equipment may also be considered regardless of any project expansion at a later date as AVEC gains operational experience with the system and as deemed appropriate. 23 of 26 Operations Planning Once the completed Emmonak/Alakanuk project is commissioned, AVEC will incorporate the new wind- diesel system into the cooperative’s existing operational and maintenance programs that are in place across the utility’s network of generation facilities. The project will be operated in a manner that will provide the greatest level of fuel savings possible. Currently, AVEC employs numerous individuals that have received factory direct training regarding the installation, operation, and regular maintenance procedures of the turbines that will be installed in Emmonak. AVEC has sent participants to Northern Power’s Level I and Level II wind technician trainings since 2005. These trainings occur at various times throughout the year. In anticipation of this particular project, AVEC sent a local resident from Emmonak to the turbine training in 2009 to make sure that there will be at least one individual with an understanding of the installed generators in the community. Once the project is commissioned, AVEC will follow the regular annual maintenance procedures outlined in Operation and Maintenance manuals supplied by Northern Power. These practices are consistent with the procedures that are implemented at all existing wind-diesel facilities maintained by AVEC. The completed project will be incorporated in the cooperative’s over-all depreciation schedules, maintained, and operated consistent with all other generation assets that are managed by the cooperative. The project presents no challenges or necessary changes to existing business practices maintained by AVEC. The installed turbines are covered under a two year manufacturer’s warranty which includes all parts and labor associated with repairs under this break-in period. Once this period expires, AVEC will maintain responsibility for performing any necessary repair or maintenance work. This procedure is identical to all other wind-diesel systems managed by the cooperative including those funded through AEA’s Renewable Energy Fund program. Due to the low penetration level of the completed system, the project is anticipated to produce a limited about of energy that is utilized for thermal/heating applications. As a result, AVEC will utilize all thermal energy generated by the installed turbines at the power plant in Emmonak. No thermal sales agreement will be organized under the scope of this project. Should the project be expanded at a later date (additional installed turbines), AVEC will re-evaluate the potential availability of thermal/excess energy supplies and determine if enough will be produced to justify generating a thermal sales agreement and appropriate transmission infrastructure for these energy supplies. AVEC has also considered the long term performance of certain integration components and their impact on anticipated O/M costs. In particular, AVEC will utilize the proposed Secondary Load Controlling equipment as tools to keep all turbines running as much as possible. These considerations prevent AVEC from having to manually shut down turbines in periods of high winds and low loads, which results in reduced wear on components (less mechanical stops) and generally improved turbine performance over the long term. 24 of 26 Attached to this document are complete warranty terms for the procured Northwind turbines, an operation and maintenance manual for the turbines, and sample curriculum of Northern Power factory training. 25 of 26 Attachments 1. Project Master Schedule 2. Emmonak, Alaska Wind Power Report (Rev. 5) 3. Emmonak and Alakanuk HOMER Modeling File (electronic file) 4. Recorded Emmonak Load Data (15 Minute Profile – July, 2009 – July, 2010 – electronic file) 5. Recorded Alakanuk Load Data (15 Minute Profile – June, 2010 – July, 2010 – electronic file) 6. Emmonak Project Updated Financial Analysis (electronic file) 7. Project Geotech Report 8. Project Foundation Drawings (95% level) 9. Project Site Access/Layout Drawings a. Option 1 – Potential future installation sites b. Option 2 – Installation site for this project 10. FAA Determination of No Hazard Notices for Option 2 Turbine Sites 11. Electrical Intertie Design (95% level) 12. Electrical System Diagrams a. Emmonak/Alakanuk One-Line System Diagram b. Quinhagak Wind Tower Electrical Details (identical to Emmonak install – 3 Sheets) c. Quinhagak 100B Wind Tower 4-Wire Grounded Wye Electrical Details (identical to Emmonak install) d. Quinhagak Ethernet / SCADA Network Design (identical to Emmonak install – 3 Sheets) e. Northern Power Wind Dispatch Controller Overview for Quinhagak (identical to Emmonak install) 13. Emmonak Powerhouse Drawings a. Existing Emmonak Heat Recovery System b. Emmonak Plant Diagrams (15 sheets) c. Location Drawings for New Emmonak Switchgear (3 sheets) 14. Bill of Materials a. Intertie Materials Take Off List b. Turbine Sales Agreement (Includes Warranty Information) 15. Northern Power Northwind 100 O/M Manual 16. Sample Northern Power Wind Technician Training Program Outline 26 of 26 Activity IDResponsDepartmeActivity NameAtompletionActivity%CompleteStartFinishEMNK EmmonEMNK EmmonakEMNK Emmonak924d01-Jan-08 A15-Jul-11Emmonak Four WEmmonak Four Wind TurbEmmonak Four Wind Turbines (WO 9720731)924d01-Jan-08 A15-Jul-11EMNK.WND.1550A.MMReduced Scope from 5 to 4 Turbines0d100%03-Aug-10 AEMNK.WND.1520A.MMSuspend Work0d100%04-Aug-10 AEMNK.WND.1530A.MMInactivity Due to Lack of Funding1d100%04-Aug-10 A05-Aug-10 AEMNK.WND.1540A.MMResume Work0d100%05-Aug-10 AConceptual DesignConceptual Design ReportConceptual Design Report261d01-Jan-08 A31-Dec-08 ASite ControlSite ControlSite Control360d01-Mar-10 A15-Jul-11EMNK.WND.1400A.MMDecide Which Site to Use (driven by FAA permitting)5d0%17-Sep-1024-Sep-10Site 1 (Near School)Site 1 (Near School)Site 1 (Near School)360d01-Mar-10 A15-Jul-11Convey to AVECConvey to AVECConvey to AVEC0d01-Mar-10 A01-Mar-10 ASurveySurveySurvey5d07-Apr-1111-Apr-11EMNK.WND.1260A.MMSurvey after Tower Erection5d0%07-Apr-1111-Apr-11Replat and RecordReplat and RecordReplat and Record60d12-May-1110-Jul-11EMNK.WND.1270A.MMReplat and Record Site 160d0%12-May-1110-Jul-11Convey BackConvey BackConvey Back5d11-Jul-1115-Jul-11EMNK.WND.1290A.MMConvey Excess Back to City5d0%11-Jul-1115-Jul-11Site 2 (Met Tower)Site 2 (Met Tower)Site 2 (Met Tower)360d01-Mar-10 A15-Jul-11Convey to AVECConvey to AVECConvey to AVEC137d01-Mar-10 A07-Sep-10EMNK.WND.1320A.MMStatement of Non-Objection Received0d100%01-Mar-10 A01-Mar-10 AEMNK.WND.1340A.MMLease Agreement-City22d100%17-May-10 A16-Jun-10 AEMNK.WND.1480A.MMLease Agreement-Corporation65d100%17-May-10 A13-Aug-10 AEMNK.WND.1580Record Leases30d0%09-Aug-1007-Sep-10SurveySurveySurvey5d07-Apr-1111-Apr-11EMNK.WND.1300A.MMSurvey After Tower Erection5d0%07-Apr-1111-Apr-11Replat and RecordReplat and RecordReplat and Record60d12-May-1110-Jul-11EMNK.WND.1310A.MMReplat and Record Site 260d0%12-May-1110-Jul-11Convey BackConvey BackConvey Back5d11-Jul-1115-Jul-11EMNK.WND.1330A.MMConvey Excess Back to City5d0%11-Jul-1115-Jul-11PermittingPermittingPermitting266d01-Apr-10 A07-Apr-11EMNK.WND.1240SOLPermit Package Preparation (combined with intertie)87d29.82%03-Jun-10 A01-Oct-10EMNK.WND.1250SOLPermit Package Review (combined with intertie)22d0%09-Aug-1007-Sep-10EMNK.WND.1230A.MMNotify FAA Tower Erected1d0%07-Apr-1107-Apr-11Site 1 (Near School)Site 1 (Near School)Site 1 (Near School)122d01-Apr-10 A17-Sep-10EMNK.WND.1350V3EFAA Review Permit Application61d100%01-Apr-10 A01-Jun-10 AEMNK.WND.1360V3EFAA Initial Rejection of Permit0d100%01-Jun-10 AEMNK.WND.1470V3EFAA Review New Permit Application69d17.14%11-Jun-10 A17-Sep-10EMNK.WND.1490V3EFAA VOR Electromagnetic Interference Analysis50d0%12-Jul-10 A17-Sep-10EMNK.WND.1510A.MMEmmonak Native Corp Letter of Support0d100%29-Jul-10 ASite 2 (Met Tower)Site 2 (Met Tower)Site 2 (Met Tower)84d01-Apr-10 A28-Jul-10 AFundingFundingFunding32d17-May-10 A30-Jun-10 AEMNK.WND.1020A.AWAEA Grant Agreement Expected32d100%17-May-10 A30-Jun-10 AEngineeringEngineeringEngineering148d01-Apr-10 A25-Oct-10Contract EngineerinContract Engineering (STG MContract Engineering (STG Managing)132d01-Apr-10 A01-Oct-10EMNK.WND.1120S.DMGeotechnical Survey22d100%01-Apr-10 A03-May-10 AJunJulAugSepOctNovDecJanFebMarAprMayJunJulAugSepOctNovDec20102011 Emmonak-Alakanuk Intertie (WO 9710751)... Multi-Project 1AVEC SchedulerSean Robbinssrobbins@avec.crg; 351-4752Page 1 of 3Printed 14-Sep-10 14:39Remaining Level of EffortActual Level of EffortPrimary BaselineActual WorkRemaining WorkCritical Remaining WorkBaseline Miles...MilestoneAVEC Project Schedule By Village and Project Data Date: 09-Aug-10 Activity IDResponsDepartmeActivity NameAtompletionActivity%CompleteStartFinishEMNK.WND.1150S.DMCivil Engineering60d100%12-May-10 A04-Aug-10 AEMNK.WND.1160S.DMStructural Engineering34d100%17-Jun-10 A04-Aug-10 AEMNK.WND.1500S.DMGeotechnical Report2d100%09-Aug-10 A11-Aug-10 AEMNK.WND.1151S.DMRemaining Civil Engineering - BBFM35d0%09-Aug-10 A24-Sep-10EMNK.WND.1161S.DMRemaining Structural Engineering-BBFM30d0%09-Aug-10 A17-Sep-10EMNK.WND.1570S.DMDistribution Design (Greg Errico)15d0%09-Aug-10 A27-Aug-10EMNK.WND.1590S.DMDesign Access to Wind Turbine15d0%09-Aug-1027-Aug-10EMNK.WND.1410A.MMAVEC Review Base Design5d0%24-Sep-1001-Oct-10AVEC EngineeringAVEC EngineeringAVEC Engineering21d24-Sep-1025-Oct-10EMNK.WND.1220A.MMEngineering Authorization to Proceed1d0%24-Sep-1027-Sep-10EMNK.WND.1030AENEngineer the Distribution System20d0%27-Sep-1025-Oct-10Material ProcuremMaterial ProcurementMaterial Procurement205d09-Aug-10 A21-May-11EMNK.WND.1040APRBuy Turbines from STG (already on-hand in VT)11d100%09-Aug-10 A20-Aug-10 AEMNK.WND.1560APRProcure Turbine Transformers (9720371 Ticket 4913)13d0%11-Aug-10 A27-Aug-10EMNK.WND.1420S.DMProcure Piles and Other Install Materials30d0%27-Aug-1026-Sep-10EMNK.WND.1130S.DMShip Materils to Site with Mobilization30d0%01-Sep-1030-Sep-10EMNK.WND.1200APRProcure Materials for Distribution System20d0%25-Oct-1014-Nov-10EMNK.WND.1180S.DMProcure and Deliver Cap Rock20d0%02-May-11*21-May-11FabricationFabricationFabrication41d27-Aug-1007-Oct-10EMNK.WND.1050S.DMFab Precast Turbine Bases11d0%27-Aug-1007-Sep-10EMNK.WND.1210S.DMShip Turbine Bases30d0%08-Sep-1007-Oct-10Construction (STG)Construction (STG)Construction (STG)262d31-May-10 A31-May-11CivilCivilCivil262d31-May-10 A31-May-11EMNK.WND.1430A.MMWhen STG would like to see contract award (for logistical arrangem0d100%31-May-10 AEMNK.WND.1390A.MMAward Construction Contract, NTP (based on funding)0d100%09-Aug-10 A09-Aug-10 AEMNK.WND.1060S.DMMobilize (in conjunction with Intertie)30d0%01-Sep-10*30-Sep-10EMNK.WND.1140S.DMConstruct Road and Pad30d0%01-Feb-11*02-Mar-11EMNK.WND.1170S.DMInstall cap rock / fine grade road and pad10d0%22-May-1131-May-11StructuralStructuralStructural35d03-Mar-1106-Apr-11EMNK.WND.1190S.DMDrive Piles14d0%03-Mar-1116-Mar-11EMNK.WND.1070S.DMErect Turbines21d0%17-Mar-1106-Apr-11InstallationInstallationInstallation45d16-Feb-1101-Apr-11Distribution SystemDistribution SystemDistribution System30d16-Feb-1118-Mar-11EMNK.WND.1080AOPAVEC Ops Install Distribution30d0%16-Feb-1118-Mar-11ConnectionConnectionConnection1d22-Mar-1122-Mar-11EMNK.WND.1090AOPConnect Power to Turbine1d0%22-Mar-1122-Mar-11CommissioningCommissioningCommissioning10d23-Mar-1101-Apr-11EMNK.WND.1440A.BTCommission Installation5d0%23-Mar-1127-Mar-11EMNK.WND.1100NPSNorthern Power Commission Turbines5d0%28-Mar-1101-Apr-11As-BuiltingAs-BuiltingAs-Builting15d02-Apr-1116-Apr-11EMNK.WND.1110A.BTDocument Control Logic2d0%02-Apr-1103-Apr-11EMNK.WND.1450S.DMProvide As-Built Information to AVEC5d0%07-Apr-1111-Apr-11EMNK.WND.1460AENPick Up Red Line Data into Drawings5d0%12-Apr-1116-Apr-11Emmonak-AlakanEmmonak-Alakanuk IntertEmmonak-Alakanuk Intertie (WO 9710751)602d01-Jan-09 A24-Apr-11EMNK.ALKN.1280A.BTStand Down Due to Revoked Funding0d100%04-Aug-10 AEMNK.ALKN.1290Funding Delay1d100%04-Aug-10 A05-Aug-10 AEMNK.ALKN.1300A.BTResume Work0d100%05-Aug-10 AConceptual DesignConceptual Design ReportConceptual Design Report260d01-Jan-09 A31-Dec-09 ASite ControlSite ControlSite Control245d17-May-10 A24-Apr-11JunJulAugSepOctNovDecJanFebMarAprMayJunJulAugSepOctNovDec20102011 Emmonak-Alakanuk Intertie (WO 9710751)... Multi-Project 1AVEC SchedulerSean Robbinssrobbins@avec.crg; 351-4752Page 2 of 3Printed 14-Sep-10 14:39 Activity IDResponsDepartmeActivity NameAtompletionActivity%CompleteStartFinishConvey to AVECConvey to AVECConvey to AVEC39d17-May-10 A09-Jul-10 ASurveySurveySurvey20d16-Mar-1104-Apr-11EMNK.ALKN.1000A.MMSurvey Final Installation20d0%16-Mar-1104-Apr-11Replat and RecordReplat and RecordReplat and Record20d05-Apr-1124-Apr-11EMNK.ALKN.1010A.MMReplat Utility Easement and Record20d0%05-Apr-1124-Apr-11PermittingPermittingPermitting69d03-Jun-10 A07-Sep-10Solstice Task OrderSolstice Task Order #4Solstice Task Order #469d03-Jun-10 A07-Sep-10EMNK.ALKN.1130SOLPrepare USACE Permit Package (intertie and turbines)1d100%03-Jun-10 A04-Jun-10 AEMNK.ALKN.1140SOLUSACE Permit Review (intertie and turbines)22d0%09-Aug-1007-Sep-10EMNK.ALKN.1230SOLCoastal Zone Determination (intertie and turbines)22d0%09-Aug-1007-Sep-10EMNK.ALKN.1240SOLEndangered Species Rever (intertie and turbines)22d0%09-Aug-1007-Sep-10EMNK.ALKN.1250SOLHIstoric Preservation Review (intertie and turbines)22d0%09-Aug-1007-Sep-10FundingFundingFunding102d03-May-10 A13-Aug-10EMNK.ALKN.1150A.AWAEA Grant Agreement Expected102d95.1%03-May-10 A13-Aug-10EMNK.ALKN.1210HUBEconomic Feasibility Analysis45d100%17-May-10 A01-Jul-10 AEMNK.ALKN.1030A.AWAEA (Common Wind/Intertie) 97207510d0%13-Aug-10EngineeringEngineeringEngineering72d16-Apr-10 A28-Jul-10 AContract EngineerinContract Engineering (Errico Contract Engineering (Errico via STG)72d16-Apr-10 A28-Jul-10 AMaterial ProcuremMaterial ProcurementMaterial Procurement80d14-Aug-1001-Nov-10EMNK.ALKN.1060S.DMSTG Procure Materials50d0%14-Aug-1002-Oct-10EMNK.ALKN.1120S.DMShip Materils to Site with Mobilization30d0%03-Oct-1001-Nov-10Construction (STG)Construction (STG)Construction (STG)240d17-May-10 A15-Apr-11CivilCivilCivil240d17-May-10 A15-Apr-11EMNK.ALKN.1190A.MMAward Contract / NTP (when STG would like it for logistics/materials5d100%17-May-10 A21-May-10 AEMNK.ALKN.1070S.DMMobilize30d0%14-Aug-1012-Sep-10EMNK.ALKN.1180A.MMNTP (based on funding)5d100%16-Aug-10 A20-Aug-10 AEMNK.ALKN.1100S.DMClearing Brush from ROW45d0%01-Dec-10*29-Jan-11EMNK.ALKN.1110S.DMInstall Piles for Poles60d0%15-Jan-1115-Mar-11EMNK.ALKN.1200S.DMErect Poles45d0%04-Feb-1120-Mar-11EMNK.ALKN.1170S.DMHang Conductor31d0%16-Mar-1115-Apr-11JunJulAugSepOctNovDecJanFebMarAprMayJunJulAugSepOctNovDec20102011 Emmonak-Alakanuk Intertie (WO 9710751)... Multi-Project 1AVEC SchedulerSean Robbinssrobbins@avec.crg; 351-4752Page 3 of 3Printed 14-Sep-10 14:39 Emmonak, Alaska Wind Power Report Report by: Douglas Vaught, P.E., V3 Energy, LLC, Eagle River, Alaska Date of Report: August 31, 2010 (revision 5) Photos: Doug Vaught Summary Information...................................................................................................................................2 Data Quality Control.....................................................................................................................................3 Wind Speed Data Summary..........................................................................................................................4 Long-term Wind Reference...........................................................................................................................5 Wind Turbine Performance ..........................................................................................................................6 Wind Farm.....................................................................................................................................................7 Village Load...............................................................................................................................................7 Wind Farm Performance...........................................................................................................................8 Loads and Energy Production, Four (4) NW100/21 Turbines...............................................................9 Loads and Energy Production, Six (6) NW100/21 Turbines................................................................10 Met Tower Data..........................................................................................................................................12 Anemometer Data ..................................................................................................................................12 Extreme Winds........................................................................................................................................13 Wind Shear..............................................................................................................................................14 Probability Distribution Function............................................................................................................14 Wind Roses..............................................................................................................................................15 Air Temperature and Density..................................................................................................................15 Speed vs. Temperature Scatterplot....................................................................................................16 Turbulence..............................................................................................................................................16 Emmonak Wind Power Report, rev. 5 Page 2 Summary Information Alaska Village Electric Cooperative (AVEC) is planning a wind power project in the village of Emmonak that will include approximately 400 to 600 kW of installed wind turbine capacity, an electrical intertie to the nearby village of Alakanuk, and a control system to integrate the turbines to the existing power sys- tem. In anticipation of this project, a met tower was installed in Emmonak in July, 2007 and continues to collect data. In addition to wind data collection, AVEC collects other information such as electric load and diesel power plant performance data for Emmonak and Alakanuk. This data was analyzed with software tools to evaluate the wind resource itself and to predict the performance of wind turbines and their operation as a wind-diesel hybrid system once connected to the village’s existing power system. The Emmonak met tower site is located on the tundra in a clearing of willow trees just west of the vil- lage boundary. This site was selected based on the intended location for wind power development in 2007, but later plans call for turbines to be placed in an open clearing in the north-central portion of the village. Given the uniform terrain characteristics of Emmonak, the met tower site is considered reason- ably representative of the new turbine site, although aspects of the data indicate an undesirable influ- ence of the brush surrounding the met tower. If wind turbines are installed at or near the met tower location, plans call for the brush to be cleared sufficiently to mitigate this problem. Met Tower Data Synopsis Data dates September 25, 2007 to April 14, 2010 (31 months; 9 months missing) IEC 61400-1, 3rd ed. classification III-b (measured);likely III-c Power density mean, 30 m 181 W/m2 (not AWOS adjusted) Wind speed mean, 30 m 5.72 m/s (AWOS data adjusted) Maximum 10-min wind speed average 19.5 m/s (not AWOS adjusted) Maximum wind gust 29.1 m/s (March 2009) Weibull distribution parameters k = 2.13, c = 5.90 m/s (to date) Roughness class 3.60 (forest) Power law exponent ()0.297 (high wind shear possibly affected by brush; lower value, more typical of tundra, likely) Frequency of calms (4 m/s threshold)35% Mean turbulence intensity 0.135 (IEC3 turbulence category B; possible brush effect, likely IEC3 turbulence category C) Emmonak Wind Power Report, rev. 5 Page 3 Google Earth image Google Earth Image of Emmonak Data Quality Control Data was filtered to remove obvious icing events. Typically, anemometer icing is identified by non- variant data readings at the sensor offset value for anemometers and a “frozen” heading for wind vanes, a standard deviation of zero, and temperature near or below freezing. The data collected to date in Emmonak indicates a number of icing events typical of freezing rain at a low elevation site. These pe- riods of data loss are shown in the graph below as thin while lines in the colored data fields and are not significant. More substantially, note that nine months of data are missing – from December 11, 2007 to April 5, 2008 and again from September 12, 2009 to February 22, 2010. The first data loss period oc- curred when a data card failed and data was unrecoverable. The second data loss period is unexplained at present but may indicate a problem with the datalogger. Also note that the met tower was installed in Emmonak on July 20, 2007. The data card containing data logged from July 20 to September 25, 2007 was lost in the mail. Emmonak Wind Power Report, rev. 5 Page 4 Data recovery rate summary Label Ch Units Height Possible Records Valid Records Recovery Rate (%) Speed 30 m A 1 m/s 30 m 134,124 89,797 67.0 Speed 30 m B 2 m/s 30 m 134,124 88,937 66.3 Speed 20 m 3 m/s 20 m 134,124 88,940 66.3 Direction 30 m 7 ° 30 m 134,124 89,554 66.8 Temperature 9 °C 2 m 134,124 93,792 69.9 Data coverage chart Wind Speed Data Summary The primary data of interest from the met tower is from the 30 meter anemometer. This data set is used for the wind turbine power generation calculations in this report. An annual summary (mean of monthly means) from the 30 meter A anemometer is presented below. 30 meter anemometer summary Month Mean Max Std. Dev. (m/s) (m/s) (m/s) Jan 4.69 16.4 2.68 Feb 6.07 19.2 3.49 Mar 6.48 18.7 2.87 Apr 5.56 15.1 2.46 May 4.89 11.1 1.86 Jun 4.73 13.8 2.07 0.00 2.00 4.00 6.00 8.00 30 meter wind speed Emmonak Wind Power Report, rev. 5 Page 5 Jul 5.05 15.5 2.13 Aug 4.58 11.8 1.76 Sep 4.72 13.3 2.05 Oct 4.79 18.7 2.59 Nov 5.13 19.4 3.14 Dec 6.77 19.2 3.06 Annual 5.29 19.4 2.58 Long-term Wind Reference The nearby Emmonak Airport has an Automated Weather Observing System (AWOS) that has collected data for many years. To gain a perspective of wind conditions during the met tower test period, AWOS data from 1985 to present were analyzed. Although some older data (pre-1997) is missing or otherwise appears somewhat inconsistent (especially 1993 and 1995), in general one observes that 2007 through 2009 were relatively low wind years compared to a long-term average (represented by the line titled Linear (Wind Speed)in the graph below), representing about 92.5% of the mean wind speed measured from 1985 through 2009 and 92.4% if considering just 1997 through 2009. Note that the long term trend of wind speed appears to be decreasing slightly. This may not necessarily be true with a longer term perspective of wind speeds, but for this study only a twenty-five year period was examined. To normalize the met tower data to long-term, a simple approach was employed of dividing the meas- ured mean wind speeds by 0.925, which yielded a mean annual wind speed at 30 meters of 5.72 m/s. This changes the Emmonak wind classification from Class 2 to Class 3, without consideration of air densi- ty effects on either data set. Met tower data, AWOS adjusted data table Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual 30 m A (m/s) 4.69 6.07 6.48 5.56 4.89 4.73 5.05 4.58 4.72 4.79 5.13 6.77 5.29 30 m A, AWOS corrected ’85 to ’09 (m/s) 5.07 6.57 7.00 6.01 5.29 5.12 5.46 4.95 5.10 5.18 5.55 7.32 5.72 Airport AWOS long-term data 0 2 4 6 8 EMK Airport AWOS Wind Data, 1985 -2009 Wind speed Linear (Wind speed) Emmonak Wind Power Report, rev. 5 Page 6 Wind Turbine Performance It is perhaps counterintuitive that wind power density and wind class do not correlate linearly with tur- bine power output. This is due to a number of factors, including theoretical limitations of a lift- producing aerodynamic device (the turbine rotor) and practical limitations of generator weight and rated output. For these reasons and others, a wind turbine in a low power class wind regime may still produce sufficient energy to warrant installation of turbines. A simplistic consideration of possible turbine output in Emmonak is to model power output of a particu- lar turbine with mean of monthly means data collected to date and extrapolating to the turbine hub height. Taking the analysis slightly further, turbine performance estimates was normalized to the long- term average wind as measured by the airport AWOS. Note the this analysis is based on raw data with no synthetic data inserted in place of icing data removed for data quality control or data missing for other reasons. Turbine performance was analyzed with the HOMER software using the Northern Power Northwind 100 B model (21 meter rotor diameter) and the Aeronautica 29-225 (225 kW, 29 meter rotor diameter). At present the NW100 is AVEC’s preferred turbine choice for Emmonak and the Aeronautica 29-225 is an alternate choice. Extrapolating to the 37, 40, and 50 meter hub heights with a power law exponent () of 0.14 instead of the met tower derived of 0.297 (note that this is a more conservative approach as extrapolated wind speeds above 30 meters are less with an of 0.14 than an of 0.297; see detailed explanation on page 12 for more information), anticipated turbine performance for 100 percent and 90 percent turbine availabilities is shown in the tables below. NW100/21 B, 37 m hub height 100% turbine avail. 80% turbine avail. 30 m mean (m/s) 37 m hub (m/s) NW100/21 (MWh/yr) NW100/21 CF (%) NW100/21 (MWh/yr) NW100/21 CF (%) Original data 5.29 5.45 177.2 19.6 141.8 15.7 AWOS- adjusted data 5.72 5.89 211.4 23.4 169.1 18.7 Emmonak Wind Power Report, rev. 5 Page 7 Aeronautica 29-225, 40 m hub height 100% turbine avail. 80% turbine avail. 30 m mean (m/s) 40 m hub (m/s) NW100/21 (MWh/yr) NW100/21 CF (%) NW100/21 (MWh/yr) NW100/21 CF (%) Original data 5.29 5.51 349.3 17.7 279.4 14.2 AWOS- adjusted data 5.72 5.95 427.2 21.7 341.8 17.4 Aeronautica 29-225, 50 m hub height 100% turbine avail. 80% turbine avail. 30 m mean (m/s) 50 m hub (m/s) 29-225 (MWh/yr) 29-225 CF (%) 29-225 (MWh/yr) 29-225 CF (%) Original data 5.29 5.68 384.6 19.5 307.7 15.6 AWOS- adjusted data 5.72 6.14 466.5 23.7 373.2 19.0 Wind Farm AVEC has proposed construction of an intertie to electrically connect Emmonak to the village of Alaka- nuk, located approximately twelve kilometers (7.5 miles) southwest of Emmonak on the Alakanuk Pass of the Yukon River. HOMER software was used to create a combined Emmonak-Alakanuk village simula- tion model. Village Load A combined Emmonak and Alakanuk hourly load profile was created with total village electric load data that have been collected since July 2009 in Emmonak and June 2010 in Alakanuk. The Emmonak data comprised more than one year and duplicate dates were averaged to create a typical annual load. Be- cause the Alakanuk data represents less than one year of data, the two months of data available were compared corresponding days and times of the Emmonak load and an average ratio calculated. This ratio – 0.512 – was used to scale the Emmonak data up to create a virtual a virtual Emmonak-Alakanuk village with a 687 kW average load, 1,053 kW peak load, approximate 380 kW minimum load, and aver- age daily power usage of 16.5 MWh/day. Seasonal, daily and DMap profiles of the Emmonak-Alakanuk virtual load are shown below. Emmonak Wind Power Report, rev. 5 Page 8 Load profile graphs Wind Farm Performance AVEC plans call for construction of 400 to 600 kW of wind turbine installed power capacity in Emmonak. The likely will be four to six Northwind 100/21 B model (100 kW rated output) wind turbines or alterna- tively two to three Aeronautica 29-225 (225 kW rated output) wind turbines. NW100 and Aero 29-225 performance table, 100% turbine availability Turbine No. Hub ht. Sys. Wind Penetration Turbine CF Wind prod. Displ. fuel Excess Energy Excess Energy (m) (%) (%) MWh/yr (gal) MWh/yr (%) NW100/21 4 37 14.1 23.4 846 55,644 0 0.0 5 37 17.6 23.4 1,057 69,440 1 0.0 6 37 21.1 23.4 1,268 82,874 9 0.2 Aero 29-225 2 40 14.2 21.7 854 56,174 0 0.0 3 40 21.2 21.7 1,281 83,019 22 0.4 2 50 15.5 23.2 933 61,308 0 0.0 3 50 23.2 23.3 1,340 90,391 28 0.5 Notes: 1. Wind resource based on Emmonak met tower, EMO-AUK intertied 2. HOMER modeling assumes 100% turbine availability 3. Displaced fuel estimate is for electrical generation only 4. Excess electricity to dump, preferably heat recovery for thermal load 5. SLC may be necessary to avoid curtailment of turbines Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ann 200 400 600 800 1,000 1,200 Seasonal Profile max daily high mean daily low min 0 6 12 18 24 0 200 400 600 800 Daily Profile Hour Emmonak Wind Power Report, rev. 5 Page 9 NW100 and Aero 29-225 performance table, 80% turbine availability Turbine No. Hub ht. Sys. Wind Penetration Turbine CF Wind prod. Displ. fuel Excess Energy Excess Energy (m) (%) (%) MWh/yr (gal) MWh/yr (%) NW100/21 4 37 11.3 18.7 437 44,515 0 0.0 5 37 14.1 18.7 845 55,552 1 0.0 6 37 16.9 18.7 1,014 66,299 7 0.1 Aero 29-225 2 40 11.4 17.4 683 44,939 0 0.0 3 40 17.0 17.4 1,025 66,415 18 0.3 2 50 12.4 18.6 746 49,046 0 0.0 3 50 18.6 18.6 1,072 72,313 22 0.4 Notes: 1. Wind resource based on Emmonak met tower, EMO-AUK intertied 2. 80% turbine availability assumed 3. Displaced fuel estimate is for electrical generation only 4. Excess electricity to dump, preferably heat recovery for thermal load 5. SLC may be necessary to avoid curtailment of turbines Loads and Energy Production, Four (4) NW100/21 Turbines The graphs below indicate predicted energy production of four (4) NW100/21 turbines operating to supply a combined Emmonak-Alakanuk village load with existing diesel generation capacity. Note the assumption of 100 percent turbine availability. Monthly average electric production, 4 NW100 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 0 200 400 600 800 Monthly Average Electric Production Wind CAT 337 CAT 505 CMS 557 CAT 908 CMS 350 CMS 499 Emmonak Wind Power Report, rev. 5 Page 10 Monthly average wind penetration, 4 NW100 Monthly average wind production, 4 NW100 Loads and Energy Production, Six (6) NW100/21 Turbines The graphs below indicate predicted energy production of six (6) NW100/21 turbines operating to supply a combined Emmonak-Alakanuk village load with existing diesel generation capacity. Note the assumption of 100 percent turbine availability. 0 100 200 300 400 500 600 700 800 900 1000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Avg Penetration, 4 NW100's Low Load Avg Load High Load High of 4 NW100 Avg of 4 NW100 - 2,000 4,000 6,000 8,000 10,000 12,000 14,000 16,000 18,000 20,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Monthly Avg Load/Wind, 4 NW100's Avg Daily Load High Daily Wind Avg Daily Wind Emmonak Wind Power Report, rev. 5 Page 11 Monthly average electric production, 6 NW100 Monthly average wind penetration, 6 NW100 Monthly average wind production, 6 NW100 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 0 200 400 600 800 Monthly Average Electric Production Wind CAT 337 CAT 505 CMS 557 CAT 908 CMS 350 CMS 499 0 100 200 300 400 500 600 700 800 900 1000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Avg Penetration, 6 NW100's Low Load Avg Load High Load High of 6 NW100 Avg of 6 NW100 - 5,000 10,000 15,000 20,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Monthly Avg Load/Wind, 6 NW100's Avg Daily Load High Daily Wind Avg Daily Wind Emmonak Wind Power Report, rev. 5 Page 12 Met Tower Data Presented below is information regarding the met tower installed in 2007 in Emmonak and pertinent technical information regarding data results. Met tower location summary information Site number 0007 Site Description Tundra clearing among willow brush northwest of Emmonak Latitude/longitude N 62° 46.964’, W 164° 33.447’, WGS 84 Site elevation 3 meters Datalogger/modem type NRG Symphonie/no modem Tower type NRG 30-meter tall tower, 102 mm (4 inch) diameter Anchor type Buried plate Tower sensor information Channel Sensor type Height Multiplier Offset Orientation 1 NRG #40C anemometer 30 m (A)0.765 0.35 North 2 NRG #40C anemometer 30 m (B)0.765 0.35 East 3 NRG #40C anemometer 20 m 0.765 0.35 North 7 NRG #200P wind vane 30 m 0.351 080 West 9 NRG #110S Temp C 2 m 0.136 -86.383 Anemometer Data Met tower anemometer data is presented below, although note that the met tower test period of late 2007 to 2009 apparently was dominated by lower than long-term average winds (see earlier discussion). Anemometer summary data Variable Speed 30 m A Speed 30 m B Speed 20 m Measurement height (m) 30.0 30.0 20.0 Annual mean wind speed (m/s) 5.29 5.24 4.74 Max wind speed (m/s) (10-min) 19.4 19.5 18.0 Max wind speed (m/s) (gust) 28.3 29.1 26.8 Weibull k 2.13 2.05 2.08 Weibull c (m/s) 5.91 5.83 5.28 Annual mean power density (W/m²) 181 180 134 Mean energy content (kWh/m²/yr) 1,584 1,578 1,172 Energy pattern factor 1.83 1.89 1.89 Frequency of calms (%) 34.3 35.2 43.6 1-hr autocorrelation coefficient 0.923 0.922 0.922 Diurnal pattern strength 0.067 0.074 0.109 Hour of peak wind speed 18 18 17 Emmonak Wind Power Report, rev. 5 Page 13 Anemometer Monthly Time Series Extreme Winds Emmonak classifies as IEC 61400-1, 3 rd edition Class III, the most common category of extreme wind classification and that for which most wind turbines are designed. Return Extreme Wind Speed (m/s) Period (yr) 10-min means Gusts 20 25.5 36.3 25 26.2 37.4 50 28.3 40.5 100 30.3 43.5 IEC 50-year extreme wind Class Vref (10 min, m/s) I 50.0 II 42.5 III 37.5 S mfr specified Wind Shear The power law exponent was calculated at 0.297 for all wind directions, indicating higher than expected wind shear at the Emmonak test site. Note however that the measured high wind shear is very likely influenced by the brush surrounding the test site. If turbines are installed in more open terrain and at hub heights exceeding 30 meters, it is likely that shear values will be less than calculated. To extrapolate data to levels higher than 30 meters, a power law exponent () value of 0.14, typical of open tundra ter- rain, was used throughout this report. Probability Distribution Function The probability distribution function (PDF) provides a visual indication of measured wind speeds in one meter per second or smaller “bins”. Note that most wind turbines do not begin to generate power until the wind speed at hub height reaches 4 m/s, known as the “cut-in” wind speed. The black line in the graph is a best fit Weibull distribution. The Weibull shape factor (k) value of 2.13 is near the “normal” shape curve k value of 2.0, also known as the Raleigh distribution. Emmonak Wind Power Report, rev. 5 Page 15 Wind Roses Winds at the Emmonak met tower test site are primarily northerly to northeasterly and to a lesser ex- tent easterly to southeasterly winds. Importantly though, southeasterly winds are higher strength, hence the power density rose indicates an approximately equal share of northerly, northeasterly and southeasterly power-producing winds at the met tower site. Note that a wind threshold of 4 m/s was selected for the definition of calm winds. This wind speed represents the cut-in wind speed of most wind turbines. By this definition, the Emmonak site expe- rienced 35 percent calm conditions during the measurement period (see wind frequency rose below). This percentage was not adjusted based on adjustment to the AWOS long-term average; if it were to be, calm condition percentage likely would be lower. Wind Frequency Rose Total value (power density) rose Air Temperature and Density During the measurement period, Emmonak experienced an average temperature of -1.9° C. The mini- mum recorded temperature during the measurement period was –38.6° C (February) and the maximum temperature was 27.9° C (July). Consequent to Emmonak’s cool temperatures, the average air density of 1.272 kg/m 3 is approximately four percent higher than the standard air density of 1.225 kg/m 3 (15.0° C and 101.2 kPa standard tem- perature and pressure) at 3 m elevation, indicating that Emmonak has denser air than the standard air density used to calculate turbine power curves. Emmonak Wind Power Report, rev. 5 Page 16 Speed vs. Temperature Scatterplot A scatterplot of 30m A anemometer wind speed versus temperature indicates that the higher wind ranges where wind turbine power production becomes substantial generally occur at temperatures warmer than -30° C. Although a wind turbine installed in Emmonak should be rated to -40° C, little power production will occur during periods of severe cold. Turbulence Air turbulence at the Emmonak test site during the measurement period is somewhat high, exceeding International Electrotechnical Commission (IEC) Category C criteria and classifying as IEC 3 rd Edition tur- bulence category B at the 30 meter level and as IEC turbulence category A at the 20 meter level. Turbu- lent air is highly unusual in open tundra environments and in this case is likely due to effects of the brush and vegetation surrounding the met tower. This assumption can be noted in the turbulence rose (turbulence vs. wind direction) graph which shows higher turbulence with southerly and westerly winds, the directions toward which heavy brush exists at the met tower site. It is presumed that wind turbines at hub heights exceeding 30 meters at the test location, or if located elsewhere in Emmonak less domi- nated by brush, will experience less turbulence, likely within category C criteria. Note also that turbu- Emmonak Wind Power Report, rev. 5 Page 17 lence from northerly winds (second graph) is substantially less than when considering all wind sectors (first graph). Turbulence intensity graph Turbulence intensity graph, northerly winds 0 5 10 15 20 0.0 0.1 0.2 0.3 0.4 0.5 0.6 Turbulence Intensity at 30 m, 315° - 45° Wind Speed (m/s) Representative TI IEC Category A IEC Category B IEC Category C Emmonak Wind Power Report, rev. 5 Page 18 Turbulence vs. wind direction Turbulence Table Bin Bin Endpoints Records Standard RepresentativeMidpoint Lower Upper In Mean Deviation Peak (m/s) (m/s) (m/s) Bin TI of TI TI TI 1 0.5 1.5 3,166 0.364 0.164 0.573 1.143 2 1.5 2.5 6,830 0.192 0.096 0.316 0.882 3 2.5 3.5 11,666 0.144 0.068 0.231 0.774 4 3.5 4.5 14,265 0.129 0.059 0.204 0.583 5 4.5 5.5 15,423 0.120 0.055 0.190 0.511 6 5.5 6.5 13,586 0.117 0.054 0.187 0.500 7 6.5 7.5 9,182 0.123 0.052 0.189 0.370 8 7.5 8.5 5,689 0.130 0.049 0.192 0.329 9 8.5 9.5 3,558 0.134 0.047 0.195 0.282 10 9.5 10.5 2,157 0.134 0.047 0.194 0.324 11 10.5 11.5 1,317 0.135 0.045 0.193 0.292 12 11.5 12.5 877 0.129 0.044 0.186 0.422 13 12.5 13.5 490 0.128 0.039 0.178 0.246 14 13.5 14.5 305 0.134 0.035 0.178 0.234 15 14.5 15.5 159 0.135 0.033 0.177 0.259 16 15.5 16.5 144 0.145 0.030 0.183 0.199 17 16.5 17.5 83 0.147 0.034 0.190 0.213 18 17.5 18.5 59 0.128 0.036 0.174 0.206 19 18.5 19.5 23 0.125 0.036 0.171 0.177 20 19.5 20.5 0 Duane Miller Associates Arctic & Geotechnical Engineering A member of the Golder Group of Companies Emmonak Wind Turbines Golder Associates Inc. 2121 Abbott Road, Suite 100 Anchorage, AK 99507 USA Tel: (907) 344-6001 Fax: (907) 344-6011 www.golder.com Golder Associates: Operations in Africa, Asia, Australasia, Europe, North America and South America August 16, 2010 103-95429 Mr. Dave Myers STG, Inc. 11820 South Gambell Street Anchorage, AK 99515 RE: NEW WIND TURBINES - GEOTECHNICAL INVESTIGATION AND FOUNDATION RECOMMENDATIONS - EMMONAK, ALASKA Dear Mr. Myers: 1.0 INTRODUCTION Golder Associates Inc. (Golder) is pleased to present the results of our geotechnical exploration, laboratory testing, and geotechnical recommendations for the proposed wind turbines planned in Emmonak, Alaska. Our services have been conducted in general accordance with our proposal to STG Inc. (STG) dated April 1, 2010. We understand STG has been contracted to install wind turbines in Emmonak, Alaska (Figure 1). The wind turbines will be Northwind 100 units installed along a single alignment (Figure 2). The currently proposed wind turbine alignment is located to the northwest of the main village of Emmonak. In 2008 Duane Miller Associates LLC (DMA) explored an alternative site to the east for the proposed wind towers that was ultimately abandoned because of conflicts with FAA flight paths. DMA also explored a previously proposed wind turbine site to the north of the currently proposed site. 2.0 REGIONAL SETTING 2.1 General Conditions Emmonak lies within the Yukon River delta and is situated on the northern bank of Kwiguk Pass, a channel of the Yukon River, near its mouth at the Bering Sea about 120 air miles northwest of Bethel. Emmonak is located in the Yukon Delta National Wildlife Refuge. Pleistocene and Recent delta building has played a major role in shaping the regional geography and most near-surface deposits in the area are composed of fine-grained alluvial silts and sands. Coastal wave action has probably sorted some of these silty and sandy deposits and eolian silts are commonly intermingled with surface organic deposits. The area surrounding Emmonak has low relief, and is mostly flat to very slightly rolling. Peat and organic silt deposits have accumulated in poorly drained low-lying areas. Lacustrine silt may underlie existing ponds or other low areas. The Emmonak area has been mapped within the discontinuous permafrost zone. 1 Permafrost is typically absent beneath large water bodies and adjacent to flowing streams and sloughs of the Yukon River. Near-surface permafrost may also be absent beneath low-lying wet areas. Permafrost typically underlies areas of relative higher elevation that are generally free of brushy vegetation. 1 Jorgenson et al, 2008, Permafrost Characteristics of Alaska, Proc. Ninth International Permafrost Conf., Fairbanks. In Press. Dave Myers August 16, 2010 STG Inc. 2 103-95429 Emmonak Wind Turbines Duane Miller Associates 2.2 Regional Climate Information Emmonak is located in a climate zone transitional between continental and maritime. The area receives 19 inches of precipitation a year with 50 to 60 inches of snowfall annually. Temperatures can range from -25 to 79 °F. The following table summarizes our recommended engineering design air temperature data for the Emmonak 2 analysis of air temperature records prior to 1978 to our analysis of Bethel air temperature records from 1979 to 2008. TABLE 1. ENGINEERING DESIGN CLIMATE INDICES H&J 1978 2008 Average Air Temperature 28.5 ºF 29.8 ºF Average Freezing Index 3500 ºF-days 3360 ºF-days Design Freezing Index 4600 ºF-days 4420 ºF-days Average Thawing Index 2000 ºF-days 2410 ºF-days Design Thawing Index 2500 ºF-days 2800 ºF-days Based on our revised climatic data, permafrost in the Emmonak area should be considered to be warming, particularly in lower lying micro-relief areas. 3.0 SITE CONDITIONS The proposed wind turbine site is located west of the main village of Emmonak, and consists of a linear alignment of five to six wind turbines spaced about 275 feet apart. Terrain conditions are variable across the site. The wind turbine alignment traverses areas dominated by dense willow growth and also flat areas with low tundra vegetation. Proposed turbine locations T-8 and T-11 are both located in areas with dense willow brush and proposed turbine locations T-9, T-10 and T-12 are sited in areas clear of brushy vegetation. The proposed location for turbine T-7 appears to be on the border of dense willow area and a low-lying clearing (Figure 2). At the time of our site investigation several feet of snow cover blanketed the area, with up to 5 feet of snow accumulated in the dense willow brush and about 3 feet of snow in the treeless windblown areas. 4.0 EXISTING GEOTECHNICAL INFORMATION The following geotechnical reports and ground temperature information were reviewed to provide a general understanding of subsurface conditions near the proposed Emmonak wind turbine site. Select geotechnical test borehole logs and measured ground temperature data are attached as an appendix to this report. In December 2008, DMA conducted a subsurface exploration, which consisted of drilling three boreholes to depths of 50 feet to explore an alternate wind turbine site located in a low-lying, wet, marshy area. Subsurface conditions consisted of a layer of peat and organic silt ranging between 1 and 3 feet deep underlain by a silt layer to between 8 and 14 feet. Silty sand and sand were observed beneath the silts to borehole exploration depths. All boreholes were unfrozen beneath the seasonal surface frost observed at one foot deep. In April 2008, DMA drilled six boreholes to explore an area previously proposed for the wind turbine site, to provide preliminary foundation recommendations for the proposed wind towers. The previously explored site is north of the currently proposed wind turbine site, and oriented at 90º to the current site. Subsurface conditions consisted of a surficial organic mat of peat and organic silt ranging in thickness from 3.5 to 9 feet deep with underlying layers of silt and fine sandy silt to about 14 to 19 feet deep. Beneath the silt, fine to medium grained sand and silty sand was observed in the boreholes to about 35 2 Hartman & Johnson. 1978. Environmental Atlas of Alaska. Institute of Water Resources, University of Alaska. Dave Myers August 16, 2010 STG Inc. 3 103-95429 Emmonak Wind Turbines Duane Miller Associates feet, where a thick layer of silt was observed. Silty sand generally underlies the deep silt deposit at about 50 feet deep. Two of the 6 boreholes drilled at the site were unfrozen beneath the seasonal frost. Degrading permafrost was observed in two boreholes, beneath an unfrozen zone observed between the seasonal frost and the permafrost. The bottom depth of permafrost, where observed, ranged from about 30 to 40 feet below ground surface. Average permafrost temperatures ranged between 31.5º and 32º F below 15 feet deep. 5.0 GEOTECHNICAL INVESTIGATION 5.1 Field Exploration The geotechnical field exploration was conducted on April 8 through April 10, 2010 and consisted of drilling and sampling five boreholes (EMK-1 through EMK-5) at the proposed wind turbine locations. The proposed wind turbine locations were not survey defined in the field. The proposed wind tower and borehole locations were located in the field using a handheld GPS instrument and are considered to be approximately at the proposed wind turbine locations, as identified by coordinates provided by STG. The boreholes were advanced to between 26 and 51 feet deep along the proposed wind turbine alignment. The boreholes were drilled with a skid-mounted CME-45 drill owned and operated by Discovery Drilling and equipped with 8-inch outside diameter (OD) hollow-stem auger. A CAT D6 LGP bulldozer was used to support the drill during mobilization to and around the wind turbine site. The boreholes were logged and sampled by a Golder geologist. Disturbed, but representative soil samples were obtained by drive sampling with a split-spoon sampler. The drive samples were obtained by driving a 1.4-inch inside diameter (2.0-inch OD) split-spoon sampler below the auger tip with a 140-pound manually operated hammer free falling 30-inches. Blow counts were recorded for each 6-inch interval of the drive. Drive samples were generally obtained at 5-foot intervals throughout borehole exploration depths, except where field conditions prevented sampling. All samples were visually classified in the field with representative portions retained in sealed polyethyelene bags to preserve natural moisture contents. All retained soil samples were delivered to our Anchorage laboratory for additional soil classification and index property testing. Geographic coordinates of the borehole locations were recorded with a hand-held GPS instrument. One-inch closed end PVC pipes were installed in all boreholes prior to backfilling with auger cuttings. Ground temperatures were measured in the field by an STG representative in Emmonak on April 23, 2010, after heat introduced from drilling action had dissipated from the boreholes. The soils have been classified according to the Unified Soils Classification System (USCS) according to ASTM standard D-2487-05 as described in Figure A-1. Visual ice in recovered samples has been classified as described in Figure A-2. Borehole logs are presented in Figures A-3 through A-7. Measured ground temperature graphs are presented in Figure C-1. 5.2 Laboratory Testing In the laboratory, recovered samples were re-examined to verify field classifications and to select samples for geotechnical index testing, including natural moisture content, pore water salinity, plasticity index testing, and fines content (percent passing 0.075 mm (US No. 200) sieve size). Laboratory test results are shown graphically on the borehole logs and are tabulated in the Sample Summary, Figure B-1. Plasticity testing results are shown in Figure B-2. Dave Myers August 16, 2010 STG Inc. 4 103-95429 Emmonak Wind Turbines Duane Miller Associates 6.0 SUBSURFACE CONDITIONS 6.1 Subsurface soil Conditions The subsurface conditions observed at the proposed wind turbine alignment consisted of a surficial organic mat underlain by organic silt that ranged in thickness to between 3 and 6 feet deep. Below the organic layers, silt and sandy silt were observed to between 12 and 14 feet deep in all the boreholes. The silt has no to low plasticity, with a sand content ranging from about 10 to 45 percent. Alluvial deposits consisting of interbedded sand, silty sand and thin silt interbeds were observed beneath the silt to depths ranging between 33 and 39 feet deep. Within the interbedded deposit, sand and silty sand were the most prevalent soil types. Silt underlies the sands and was observed at 33 to 39 feet deep and continued to borehole exploration depths, about 50 feet, in four of the five boreholes drilled at the proposed wind turbine site. The deeper silt deposit observed during the exploration is medium plastic and dark gray. Thermal conditions at the proposed wind turbine site vary considerably. Unfrozen conditions were observed beneath a seasonally frozen layer in two boreholes, EMK-2 and EMK-3, turbine locations T-11 and T-8, respectively. Seasonal frost was observed to 3 feet deep in both boreholes, with unfrozen conditions observed to borehole exploration depths, 49.5 feet deep. The unfrozen boreholes were drilled in areas of dense willow growth, which may indicate relatively well drained and unfrozen soil conditions. Ground temperatures measured in these two unfrozen boreholes generally ranged between 34.5 and 35.5 ºF below 20 feet deep, confirming the unfrozen conditions observed in the field. Ground water was observed at 8.5 and 6 feet in boreholes EMK-2 and EMK-3, respectively. Warm permafrost was observed in the remaining boreholes, EMK-1, EMK-4 and EMK-5, turbine locations T12, T9 and T10, respectively. These boreholes were frozen throughout exploration depths, with the exception of an unfrozen zone observed between 3 and 7.5 feet deep in borehole EMK-5. The frozen boreholes were drilled in areas with tundra vegetation and no willow cover, indicating poorly drained conditions with likely shallow seasonal thaw. Average ground temperatures measured below 20 feet deep in the frozen borings ranged between 31.6 and 31.7 ºF, indicating warm permafrost. 6.2 Laboratory Test Results Soil moisture content was measured in recovered soil samples. Average soil moisture content, as a percent of dry weight was approximately 460 percent for frozen peat samples, 100 percent for recovered frozen organic silt (OL) samples and 65 percent for unfrozen organic silt samples. Average moisture contents for the silt and sand samples were not significantly different with respect to the thermal state of the recovered sample, and averaged 33 percent for silt (ML) samples, 27 percent for silty sand samples (SM) and 24 percent for the sand samples (SP, SP-SM). The elevated moisture contents in the frozen peat and organic silt samples recovered from the upper 10 feet indicate ice may be present in excess of unfrozen state saturation. Moisture contents in the recovered frozen and unfrozen sand and silt samples generally reflect saturated conditions. Pore water salinity tests were conducted on a representative selection of recovered samples. Soils with significant pore water salinity concentrations may exhibit a freezing point depression, possibly resulting in unbonded pore water in soil with temperatures below the freezing point. Measured pore water salinity values from soils recovered from the Emmonak wind turbine site ranged between 0.1 and 1.2 parts per thousand (ppt), and averaged 0.6 ppt. The salinity levels measured in recovered samples is not expected to significantly affect the freezing point temperature of the soils. 7.0 DISCUSSION River Delta contributes to the intricate permafrost distribution in the region. Areas adjacent to water bodies, including the Yukon River and its channels, lakes, ponds, and flowing streams, are generally underlain by unfrozen ground and typically have low to high brush vegetation. Low-lying wet and marshy areas are also typically underlain by unfrozen ground, or by degrading permafrost, and may indicate the location of a drained lake or pond. Relatively higher terrain Dave Myers August 16, 2010 STG Inc. 5 103-95429 Emmonak Wind Turbines Duane Miller Associates with low tundra vegetation is more likely to be underlain by permafrost. The maximum depth of permafrost in the region is unknown, although permafrost was observed to full exploration depth, 50 feet, within the proposed wind turbine area. Degrading permafrost was observed north of the proposed wind turbine site from an upper depth of about 10 to 15 feet and continuing to about 30 to 40 feet deep, where unfrozen ground was observed beneath the permafrost. Where present, permafrost in the Emmonak area is typically warm, with temperatures generally ranging between 31 and 32 ºF. The proposed wind turbine alignment traverses ground underlain by discontinuous permafrost and varying thermal states were observed among the boreholes during the subsurface exploration. In general, boreholes that were drilled on relatively high ground clear of brushy vegetation were underlain by permafrost, and the boreholes drilled in areas of dense willow growth were underlain by unfrozen ground. The westernmost proposed wind turbine location, T-7, was not explored during the investigation. Turbine location T-7 appears to be on the border between an area densely vegetated with willow brush and an area that appears to be a low-lying wet area that may be a drained pond where the subsurface thermal conditions may be unfrozen. The subsurface soil conditions at the proposed wind turbine locations were observed to be similar among the boreholes and generally consist of a surface layer of peat and organic silt to about 6 feet deep, underlain by a silt layer with no to low plasticity to about 12 to 14 feet deep, that grades to a non-plastic sandy silt in some areas. An interbedded unit primarily composed of sand and silty sand with lesser components of silt and sandy silt, was generally observed below the silts to a depth ranging from 33 to 39 feet. Dark gray, mineral silt with medium plasticity was observed beneath the sands to borehole exploration depths. Mixtures of frozen, degrading, and thawed soils were encountered along the wind tower foundation alignment. It is desired to construct all wind turbine units on the same foundation system. The towers will be steel monotube design seated on a precast concrete cap founded on six foundation piles per tower. The towers will be approximately 120 feet tall with 68.5-foot diameter rotor. Based on foundation design loads developed by the structural engineer, we understand the maximum total loads per pile (dead and live load under design wind and icing conditions) are: Axial Uplift: 70 kip Axial Download: 100 kips Shear, 5 kips per pile (28 kips at the tower base) 8.0 CONCLUSIONS AND RECOMMENDATIONS The uppermost six feet soil is organic silt that will require stiffening to reduce the point of fixity. We are recommending the near surface organic silts be stiffened with passive subgrade refrigeration along each pile coupled with an insulated pad under and around each tower base. 8.1 Pile Foundation A nominal 16-inch diameter, open or closed-end, driven steel pipe pile is recommended for the tower foundation. At least six piles per tower will be necessary. Closed end piles may be installed in thawed soils however open end piles will most likely be required for degraded or frozen soil conditions. Pile drive points are advised for closed end piles, drive shoes are generally not necessary for open end piles. If drive shoes are desired for the open end piles, they must be flush with the pile outside diameter. To achieve the requested design loads, the piles should be embedded to a depth of at least 47 feet below the rigid insulation layer. Additional pile length will be required to accommodate the desired riser section above finish grade, assumed to not exceed three feet above the rigid insulation layer. If multiple piles are necessary under a bearing point, a minimum pile-to-pile (centerline) spacing of three (3) pile diameters is recommended. The towers will not be heated, however the base of the precast pile cap will be approximately one foot above final grade. A one foot clearance under the tower base may not allow for Dave Myers August 16, 2010 STG Inc. 6 103-95429 Emmonak Wind Turbines Duane Miller Associates adequate cold air circulation under the towers. The passive subgrade cooling will be used to compensate for the lack of blow through space under the concrete pile cap. Additions or exterior perimeter obstructions such as snow drifts, berms, or adjacent buildings that would impact the thermal regime near the tower foundations should not be present. The pile with should be embedded with a diesel hammer with a design energy of at least 40,000 foot- pound energy (APE or Delmag D16-32, or similar). Pile should be driven in a continuous manner without the need for field splices. All piles should be plumb and checked for horizontal and vertical position prior to installation. Fixed head pile leads are recommended to maintain pile alignment during installation. Free head leads may be used provided the installation contractor demonstrates the ability to achieve the installation tolerances with free head lead systems. Piles should be installed vertical and within three inches of plan location, or as determined by the structural engineer. Under no circumstances should pile be out of plumb more than six (6) inches over 10 vertical feet of embedded pile (approximately 3 degrees from vertical). 8.2 Passive Subgrade Cooling System Each pile will require subgrade cooling to develop the recommended lateral stiffness to reduce the point of fixity. A two-phase liquid-vapor, passively-cooled subgrade cooling system installed along access guides attached to the pile or adjacent to the pile in in-situ soil is recommended at each tower foundation pile. Passive subgrade cooling systems as developed by Arctic Foundations, Inc. (AFI Thermoprobes) are recommended. The AFI Thermoprobe is a passive cooling system that relies on seasonal cold ambient air temperature to achieve and maintain design ground temperatures. The passive subgrade cooling will need to reduce the existing ground temperature to a sustained temperature of 31°F or colder below the rigid insulation layer to at least 20 feet below the insulation layer. This will require a winter cooling cycle prior to loading the piles, or artificial cooling if an early tower installation is planned. The ground temperature along the uppermost 20 feet of the embedded pile should be maintained below 31.5°F prior to fully loading the piles. A series of 3.5-inch diameter AFI Thermoprobes should be installed adjacent to each pile to reduce the ground temperatures along the piles. The Thermoprobes should be installed to at least 20 feet below finish grade. Each Thermoprobe should be terminated above grade with a 70 square-foot finned condenser. The finned condenser section should be set above the surrounding grade, expected snow drift height, and the concrete pile cap. The finned condenser should also be protected from falling snow and ice. The Thermoprobes should be installed along accessways installed on the piles or three to four feet radially from the pile in nominal 5 to 6-inch diameter bore holes and backfilled with potable water to develop a thermal contact with the surrounding soil. The Thermoprobes should have corrosion protection suitable for the environment along their exposed sections and along the initial 6 feet below grade. A well- graded sand and gravel backfill is recommended 3 to 4 feet below grade along each Thermoprobe if installed in standalone bore holes. 8.3 Insulated Fill Pad An insulated fill pad should be constructed with a locally available material with a sand and gravel cap to control wind erosion. A basal geotextile such as Geotex 401, should be installed on the tundra surface prior to fill placement. Six (6) inches of 40-psi compressive strength extruded or expanded polystyrene insulation is recommended at the base of the fill section at each tower location. At each tower location, the rigid insulation should extend at least six (6) feet laterally from the pile cap footprint. The insulation should be installed as three layers of 2-inch thick insulation with overlapping and offset vertical joints. The insulated fill pads are considered non-structural and are not designed as load bearing elements. Accordingly, poorer quality, frost susceptible fill may be used for leveling and ballast over the insulation layer. However, at least 12 inches of clear space is advised between the finish pad grade and the tower concrete cap base to permit seasonal frost movements. The ballast fill section should be compacted to firm, non-yielding state, approximately 90% of maximum dry density as determined by ASTM-D 1557, modified Proctor. If the ballast fill will erode by wind or water action, a granular cap is advised over the Dave Myers August 16, 2010 STG Inc. 7 103-95429 Emmonak Wind Turbines Duane Miller Associates local fine grained fill material. The granular cap should be sufficient coarse grained and thick to reduce wind erosion to an acceptable level. If the insulated fill pads under and around the tower foundations are planned for structural loading or thawed-state construction trafficking, we should be contacted to review or modify our insulated pad recommendations. 8.4 Lateral Capacity The bending moment imposed on the piles depends on the lateral load imposed at the top of the pile and the height of the top of the pile above the point of fixity. After the near surface soil below the rigid insulation layer is frozen, the pile can be assumed to be a cantilever above the maximum depth of thaw, the point of fixity. The depth of thaw depends on the site fill thickness and insulation, design summer thawing index, the soil type(s) from finish grade, and the surface albedo (n-factor). For this site, the point of fixity is considered to be 0.5-foot below the depth of maximum surface thaw. If a nominal 1.5-foot thick fill pad with six (6) inches of basal rigid insulation is used and a winter cooling period is permitted, a design point of fixity of 0.5 feet below the insulation is recommended. If the piles are installed in the natural tundra, the point of fixity will be near the base of the organic silt layer, approximately 6 to 8 feet below grade during the maximum summer surface thaw. A point of fixity at approximately the tundra surface can be assumed during the maximum winter surface frost penetration. The lateral loads will be resisted by passive pressures against the piles, predominantly along the frozen soil portion of the pile. The deflection also depends on whether the piles are fixed or pinned at their top. For the pile foundation recommended above (nominal 16-inch diameter, standard schedule pipe pile (0.375-inch wall)) that is fixed against rotation at its top and laterally loaded to 4 kips at no more than 24 inches above ground surface, the movement at the ground surface will be less than 0.5 inches. If larger lateral loads, smaller pile diameter, or a thinner pile wall section is being considered by the design team, lateral movement may be greater. 8.5 Estimated Settlement For design purposes, we have estimated a total settlement in the range of 1-inch in 20 years. However, this settlement will depend on subsurface conditions, soil temperatures, and the pile installation being consistent with the geotechnical recommendations. 8.6 Ground Temperature Instrumentation Construction planning for the pile foundations should include adequate time after installation to allow for passive cooling systems to freeze the soil surrounding the uppermost 20 feet of the pile below the rigid insulation layer. To permit temperature measurements, a closed end, a 1-inch diameter schedule 40 (or equivalent) steel pipe should be installed along the full length of the pile and should be terminated to allow for temperature probe access at the concrete pile cap. The temperature probe access pipe should be oriented opposite the passive subgrade cooling system and should be configured to allow for ground temperature measuring strings to be installed from the surface. A weather tight cap should be placed over the top of the pipe. 9.0 REVIEW AND FIELD QUALITY CONTROL The pile installation should be monitored by a Golder representative. Pile installation as-built records should be maintained during placement and should include blows per foot of pile embedment, pile geometry, location, and installation behavior. Drive hammer energy and configuration should be noted. Any significant differences in pile installation behavior should be reported to Golder in a timely manner. The final plans and specifications should be reviewed by Golder to verify that they are in accordance with the intent of our recommendations. Anchorage, Alaska 995034831 Eagle Street2-22-00033QUINAGHAK Anchorage, Alaska 995034831 Eagle StreetAnchorage, Alaska 995034831 Eagle Street2-22-00033QUINAGHAK 2-32-9004 0MEKORYUKAnchorage, Alaska 995034831 Eagle Street Northwind® 100 Wind Turbine Dispatch Controller and SmartView Monitoring System for Quinhagak Wind Turbine Dispatch Controller for Quinhagak Contents Executive Summary ...................................................................................................................... 3 Scope of Work ................................................................................................................................ 3 Wind Turbine Dispatch ................................................................................................................. 3 SmartView Monitoring System ..................................................................................................... 3 Functions of SmartView Monitoring System ............................................................................ 3 Human Machine Interface (HMI) Configuration for Quinhagak ................................................ 4 SmartView Web Service ........................................................................................................... 5 Bill of Materials ............................................................................................................................. 5 Commissioning and Support ....................................................................................................... 6 Warranty ......................................................................................................................................... 6 Price Proposal ................................................................................................................................ 6 Pricing .......................................................................................................................................... 6 Wind Turbine Dispatch Controller for Quinhagak Executive Summary This proposal is provided in response to AVEC’s request for a system to provide wind turbine dispatch control and a SmartView Monitoring system, referred to collectively as the Wind Turbine Dispatch Controller (WTDC). The main function of the WTDC is to enable or disable wind turbine generators via a command sent over the Ethernet network, based on an analog signal provided by the diesel plant supervisory controller. The SmartView Monitoring System will provide local and remote HMI, alarm reporting, and historical trending for the wind turbine generators, the Generator Modules, the Control Module, and the feeder and generator bus power meters. Northern Power Systems (Northern) proposes to design, build, deliver and commission the WTDC as described in this document. As we currently understand it, the requirements are identical to those for Savoonga, except where noted in this proposal. This proposal includes an allowance for commissioning the WTDC following the installation of the Northwind 100 wind turbines. Scope of Work Wind Turbine Dispatch The primary goal of the wind turbine dispatch controller is to enable or disable wind turbine generators based on the Maximum Allowed Wind Power signal, an analog signal (4 – 20ma) provided by the diesel generator supervisory controller, referred to as the Diesel Controller. The accuracy of this signal is within the scope of AVEC or its subcontractors. However, we will test for the quality of this signal to the best capability of the PLC we are using, and default to a safe limit in the event of a failed signal circuit. The PLC will be equipped with an analog input card (4 channels) to receive the Maximum Wind Turbine Power signal from the Diesel Controller, and a communication card for communication with the Northwind 100 wind turbine generator controllers. The secondary goal of the turbine dispatch algorithm is to evenly distribute run time across all wind turbine generators. SmartView Monitoring System The SmartView Monitoring System will be comprised of an industrial computer located in Quinhagak running the following software: KEPServer OPC Server: provides communication interface to all controllers. SmartView Site Manager: interfaces with controllers via OPC server, processes alarm and event logic, and writes data to MySQL database. MySQL database: stores real-time and historical data for access by SmartView HMI. SmartView HMI: graphical interface application to display data on the touch panel monitor. Other ancillary applications will also be running or available on this computer. Functions of SmartView Monitoring System The SmartView Monitoring System will provide: Wind Turbine Dispatch Controller for Quinhagak Real-time status: any available signal in the SmartView system can be displayed on any screen, and it will be updated on a 1-3 second period. Data logging: all available signals in the SmartView system can be configured to be recorded in several ways: Trend: a trend provides a high resolution history of any signal in the SmartView system for 1 – 7 day period. The signal is sampled on a 1-3 second period and recorded in a database table. Trends are typically stored for 24 hours, but can be extended beyond depending on the loading of SVMS and the amount of storage available in the computer. Frame: a frame provides a low resolution history of any signal in the SmartView system for 1 – 4 years. A statistic is calculated from a trend on a periodic basis and the result is stored in a database table. Typically ten-minute averages are calculated for all trends and are stored for five years. Event: an event provides an exception-based history of any signal in the SmartView system. The signal is sampled on a 1-3 second basis, but is only recorded in the database when the value changes. This is typically used with digital signals that change infrequently, and provides more efficient processing and storage, which can improve the overall performance of the SmartView system. Alarming: Alarms indicate an abnormal condition in the monitored system. Alarms are typically based on Boolean expressions (e.g. a digital tag) and record a new record in the database when the alarm becomes “active”. The same record is later updated with another timestamp when the alarm becomes “clear”. The record remains visible in the alarm screen on the HMI until the alarm is both clear and acknowledged. Acknowledgement requires a user to click on the HMI screen. Email notification: emails will be automatically sent to the AVEC-specified users when alarms become active. The reliability of this mechanism depends on many things, some of which are not in Northern control. Therefore, Northern cannot be responsible for any problems that arise as a result of failure of email notification. Data forwarding: SmartView Site Manager has the capability to connect to remote databases and forward frame and event data. This provides the opportunity to aggregate data from multiple sites in one central database, making it easier to provide fleet-based summary reports. Human Machine Interface (HMI) Configuration for Quinhagak The HMI configuration will consist of the following screens: System Overview: high-level view of total power system. WTG Overview (3x): detailed information on Northwind 100 wind turbines. Generator Module (4x): detailed information on the diesel generators. Control Module: detailed information on Control Module, including day tank and oil blender. Feeder Screen: detailed information about each feeder, and summary information about the diesel engine generator bus and the wind turbine generators. Wind Turbine Dispatch Controller for Quinhagak No heat recovery system is planned for this village, so no screen will be provided. Northern proposes to add to the wall-mounted enclosure a keyboard and mouse that will be housed on a flip-down tray on the door of the enclosure. This would provide an operator a convenient way to enter a password. SmartView Web Service SmartView Web Service is a subscription service provided by NPS to allow AVEC users to access the HMI using their browser via the Web. An authorized user can log into the SmartView web site and see the status of all sites to which they have access, and can drill down to a particular site to see the full HMI for that site. SmartView Web Service requires that the RTU be publicly accessible on the Internet on one port at all times. This precludes the use of dial-up or on-demand internet service. SmartView Web Service uses a concurrent licensing model. This means that a customer can pay for e.g. five concurrent users, but have e.g. ten accounts in the system. Only five users will be able to access the SmartView web service at any one time. The benefit of this model is that the customer only pays for the amount of access that is required by their organization, independent of how many users need access at some time. Bill of Materials Quantity Description 1 NEMA 12 or higher wall-mounted enclosure with flip-down keyboard tray 1 Beckhoff C6240 industrial PC (RTU), keyboard and mouse 1 Industrial touch panel monitor 1 Wago PLC, 120VAC 1 Wago 4-channel analog input card & Wago analog output 1 Wago communication card 1 UPS to support RTU, PLC 1 Enclosure cooling fan 1 Thermostatic switch to control fan 1 Industrial Ethernet switch, 2 fiber optic ports, 3 RJ45 ports 2 KEPServer OPC server driver licenses, ECOM and Modbus TCP 1 SmartView Site Manager 1 MySQL Database 1 SmartView HMI 1 Power Supply Wind Turbine Dispatch Controller for Quinhagak Commissioning and Support The commissioning of the WTDC system will coincide with the installation and commissioning of the Northwind 100 wind turbines, so AVEC will only have to pay for the additional labor for this effort (no additional travel). Remote support for the system will be included for a period of one year after commissioning. If on-site work cannot be completed by AVEC personnel and a service trip is required by a Northern employee, Northern will charge on a time and expenses (T&E) basis. Warranty Northern warrants the WTDC against defects in hardware and workmanship for a period of two years after commissioning. Price Proposal Pricing Add the following Product: Wind Turbine Dispatch Controller for wind-diesel applications 1 unit $25,000/unit = $25,000 total price Add the following Services, Installation Support & Commissioning Services: Field Service wind turbine dispatch controller commissioning (ESTIMATE ONLY) 1 unit $10,500/unit = $10,500 total price Include Travel & Expenses, OCONUS/International (ESTIMATE ONLY) 1 unit $4,000/unit = $4,000 total price Include Freight to AVEC headquarters in Anchorage, AK (ESTIMATE ONLY) 1 unit $2,000/unit = $2,000 total price Product Total is $25,000 Services Total is $16,500 (ESTIMATE ONLY) Destination address to be AVEC yard, Anchorage, AK. WTDC unit to be shipped 8 weeks following receipt of order. Terms and conditions of purchase to be in accordance with Northern’s Product Sales Agreement, submitted separately. Pricing quote is valid until September 30, 2009. Anchorage, Alaska 995034831 Eagle Street 1-07-000013EMMONAKGRAPHIC SCALESWITCH ARRANGEMENTPROPOSEDDESCRIPTION OF EXIST DIKE2022215131918171516149111210786EMMONAK13422324252627FOR VERTICAL TANKS ONLYFOR HORIZONTAL TANK 26 & 27 Anchorage, Alaska 995034831 Eagle Street Anchorage, Alaska 995034831 Eagle StreetSet spike involtage lineslieu of highunderground. Anchorage, Alaska 995034831 Eagle StreetSet spike involtage lineslieu of highunderground. Anchorage, Alaska 995034831 Eagle Street Anchorage, Alaska 995034831 Eagle Street BID UNIT TAB 95% UNIT QUANTITY #2 CONC 350' 4/0 ACSR 195,000' 7 #6 COPPERWELD 30% EHS 4,600' 40/1 131 45/1 22 50/1 2 55/1 2 60/1 2 80/H1 6 2" LT FLEX 75' 3" LT FLEX 50' 2" LQD-TITE CNCTR 8 3" LQD-TITE CNCTR 4 2" COUPLING 1 3" COUPLING 1 2" GR BSHNG 6 3" GR BSHNG 2 E1-3 66 E2-3 9 F-H42-1 34 F-H42-2 16 GRID REFLECTOR 330 AVIATION ORANGE MARKER BALL 2 RED MARKER BALL 2 WHITE MARKER BALL 2 VIBRATION DAMPER 1276 M2-11-#4 1 M2-11P 165 M32-63P 165 M5-21 10 M52-3 165 VC1ALR 137 VC2ALR 4 VC7L 20 VC8L 4 VC8L-ON 3 TDDH-80 2 VA5-1 1 VM5-2 8 VM5-5 22 VM5-20 3 UM6-1 8 UM6-10 2 UM6-15 2 UM6-19 1 UMC2-3 1 Page 1 of 1 5/5/10 14. Validity Total Product Value 1,310,000$ Total Services Value -$ Subtotal 1,310,000$ Total Contract Value 1,310,000$ Item # Product Description Status Quantity Unit Price (US$) Total Price (US$) 1 Northwind ® 100 Standard wind turbine (the "Turbine"), IEC WTGS Class IIa, including 37m tower, 21m rotor, power electronics, SmartView remote monitoring system, and 2-year limited warranty. Nacelle price is EXWORKS Northern's factory, Barre, VT. 328,500$ -$ 2 Northwind ® 100 Cold-Weather wind turbine (the "Turbine"), IEC WTGS Class S, including 37m tower, 21m rotor, black hydrophobic polymer blade coating, power electronics, SmartView remote monitoring system, and 2- year limited warranty. Turbine branded with AVEC logo. Nacelle price is EXWORKS Northern's factory, Barre, VT. 4 325,000$ 1,300,000$ 3 Northwind ® 100 Canadian Market wind turbine (the "Turbine"), IEC WTGS Class IIa, including 37m tower, 21m rotor, power electronics, SmartView remote monitoring system, and 2-year limited warranty. CSA certification pending. Nacelle price is EXWORKS Northern's factory, Barre, VT. 328,500$ -$ 4 Northwind ® 100 European Market wind turbine (the "Turbine"), IEC WTGS Class IIa, 50Hz operation, including 37m tower, 21m rotor, power electronics, SmartView remote monitoring system, and 2-year limited warranty. CE certification pending. Nacelle price is EXWORKS Northern's factory, Barre, VT. 328,500$ -$ 5 21m blade set, includes 3 blades. Price is F.O.B. United States west coast port, third-party manufacturer. 4 included in Turbine price -$ 6 37m tower Price is F.O.B. Seattle port, third party manufacturer. 4 included in Turbine price -$ 7 30m tower Price is F.O.B. United States west coast port, third party manufacturer. Pre-Order; 16-week lead time 10,000$ -$ 8 Interconnect Relay & Cabinet (SEL) $ 8,500 -$ 9 FAA Light: L810 Obstruction Lighting Kit 4 $ 2,500 10,000$ 10 Auto Descent Device $ 4,400 -$ 11 Anchor Bolt Template Ring $ 3,900 -$ 12 Anchor Bolt Embedment Ring $ 4,900 -$ 13 Annual Maintenance Kit $ 500 -$ 14 Brake Pad Replacement Kit (required every 5 years) $ 2,225 -$ 15 Secondary Load Controller for Wind-Diesel Applications (ALASKA ONLY) $ 147,500 -$ 16 Extended Warranty, years 3 through 5, per year 3,200$ -$ Pricing is valid until: August 15, 2010 Delivery is valid until: September 30, 2010 1. Products Exhibit A: Products and Services Rotor Options Tower Options Miscellaneous Options Summary Warranty Options Item # Service Description Quantity Unit Price (US$) Total Price (US$) 17 Freight to site (ESTIMATE ONLY) -$ 18 Installation and O&M Training (3 day) 3,500$ -$ 19 Field Service installation support, CONUS (ESTIMATE ONLY) 7,000$ -$ 20 Field Service installation support, OCONUS/Int'l (ESTIMATE ONLY) 9,400$ -$ 21 Field Service commissioning, CONUS (ESTIMATE ONLY) 7,000$ -$ 22 Field Service commissioning, OCONUS/Int'l (ESTIMATE ONLY) 9,400$ -$ 23 Field Service secondary load controller commissioning ALASKA ONLY (ESTIMATE ONLY) 18,800$ -$ 24 Travel & expenses, CONUS (ESTIMATE ONLY) 2,000$ -$ 25 Travel & expenses, OCONUS/Int'l (ESTIMATE ONLY) 4,000$ -$ Location Seattle Departure for Emmonak 2. Product Delivery STG’s delivery of Products to the barge landing in Emmonak (or other appropriate project location defined by AVEC) shall constitute delivery to Buyer. Title to and risk of loss to the Products shall pass to Buyer upon STG's delivery of the Products to the carrier. Delivery of Products shall be made in accordance with the following estimated delivery dates. Estimated delivery date is the target by which Northern will use reasonable commercial effort to deliver Products. If earlier delivery is possible or later delivery necessary, Northern will coordinate with Buyer in good faith a suitable delivery date. All items identified as Pre-Order are subject to change in terms of availability, price or final specification. Should STG make any such modifications the item will be cancelable at the discretion of AVEC and the individual item will be subject to full refund. August 13, 2010 The preceding prices do not include taxes, tariffs, import or export duties, shipping, delivery, set fees or any materials, which are all payable by the Buyer, unless specifically listed otherwise above. Shipping Services Labor Services Travel & Expenses Budgets Labor will be invoiced according to currently published daily rates, up to 10 hours per day, then hourly rates beyond that. Current hourly rates defended in STG's existing Construction Management contract with AVEC would apply as necessary. Estimated Delivery Dates Date 3. Services Training Services All items identified as ESTIMATE ONLY will be invoiced based on actual days (labor) or cost (freight and expenses). Freight for turbine equipment from Seattle to project site will be combined with additional project materials and invoiced separately. Commissioning support from Northern Power will be required. Commissioning expenses will be invoiced as costs are incurred by Northern Power to AVEC. "Field Service Installation Support" shall consist of the following activities and will be performed by STG per existing terms defined in the existing Construction Management contract held with AVEC: - unloading - tower unpacking - grout installation - tower and nacelle rigging and hoisting - tower section placement and bolt tensioning - rotor blade pitching - rotor rigging, hoisting, placement and bolt tensioning Interconnection transformers. This Agreement specifically excludes the following items, which shall be supplied to AVEC by STG through the terms and conditions stated in previously executed Construction Management contracts between AVEC and STG: "Field Service Commissioning" shall consist of the following activities and will be performed by Northern Power representative: - verifying installation completion, electrical connections, & bolt tensioning - performing all startup activities - completing commissioning checklist - obtaining commissioning checklist signoff by End-user - issuing commissioning certificate Installation or erection labor, material, and equipment. 4. Specific Exclusions Foundation or mounting hardware for the tower-to-foundation connection. Foundation materials or foundation parts. 11820 South Gambell Street • Anchorage, Alaska 99515 • Phone: (907) 644-4664 • Fax: (907) 644-4666 E-mail: info@stgincorporated.com • Website: www.stgincorporated.com NORTHWIND® 100 WIND TURBINE OPERATIONS & MAINTENANCE MANUAL Northern Power Systems 29 Pitman Road Barre, Vermont 05641 USA Tel: 802.461.2955 Fax: 802.461.2998 www.northernpower.com Introduction Northwind 100 Wind Turbine 1-1 1 INTRODUCTION 1.1 DISCLAIMER Information in this document is provided in connection with Northern Power Systems products and services. No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted by this document except as provided. Except as provided in Northern Power Terms and Conditions of Sale for such products and services, Northern Power assumes no liability whatsoever, and Northern Power disclaims any express or implied warranty, whether written or oral, relating to sale and/or use of Northern Power products or services including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right. Northern Power products are not intended for use in medical, life saving, or life sustaining applications. Northern Power may make changes to specifications and product descriptions at any time, without notice. This Northwind ® 100 Operations and Maintenance Manual as well as any software, processes or procedures described in it is furnished under license and may only be used or copied in accordance with the terms of the license. The information in this manual is furnished for informational use only, is subject to change without notice, and should not be construed as a commitment by Northern Power. Northern Power assumes no responsibility or liability for any errors or inaccuracies that may appear in this document or any software that may be provided in association with this document. Except as permitted by such license, no part of this document may be reproduced, stored in a retrieval system, or transmitted in any form or by any means without the express written consent of Northern Power. Copyright © Northern Power 2009. All rights not expressly granted herein are reserved. Any other brands and/or names used herein are the property of their respective owners. Introduction Northwind 100 Wind Turbine 1-2 1.2 ABOUT THIS MANUAL Welcome to the Northwind® 100 Operations & Maintenance (O&M) Manual. This manual applies specifically to Northern Power System’s Northwind 100 B model wind turbines. This manual provides instructions and drawings for electrical and mechanical systems provided by Northern Power. Any personnel tasked with operating, monitoring, and maintaining this power system should be familiar with the complete documentation package and should have it available for reference. Be sure to read the important safety instructions in Section 2 - Safety Information. Introduction Northwind 100 Wind Turbine 1-3 1.3 IN THIS MANUAL The Northwind® 100 Operations & Maintenance (O&M) Manual covers all aspects of the Northwind® 100 turbine system, including operating instructions, drawings, and documentation for vendor components. This manual is organized into the following sections: ABOUT THIS MANUAL Describes how this manual is organized and includes information on typographical conventions SAFETY INFORMATION Outlines how safety is handled throughout the manual and lists general safety precautions TURBINE ARCHITECTURE Includes an overall system description SYSTEM COMPONENT DESCRIPTIONS Describes each of the major components, includes pictures of those components and describes how the components interact with the overall system DESCRIPTIONS OF TURBINE STATES Includes a description of the turbine operational states SYSTEM CONTROL Describes the methods to interface with the wind turbine OPERATIONS Describes operations tasks MAINTENANCE Describes maintenance tasks that must be performed on the system maintenance TROUBLESHOOTING Describes how to troubleshoot the system DRAWINGS AND DIAGRAMS Includes all relevant system drawings and diagrams VENDOR DOCUMENTATION Includes all relevant component documentation Introduction Northwind 100 Wind Turbine 1-4 1.4 TABLE OF CONTENTS 1 Introduction.........................................................................................................1-1 1.1 Disclaimer ..............................................................................................1-1 1.2 About this Manual .................................................................................1-2 1.3 In this Manual.........................................................................................1-3 1.4 Table of Contents ..................................................................................1-4 1.5 Typographical Conventions.................................................................1-7 1.6 Getting Help...........................................................................................1-7 2 Safety Information..............................................................................................2-1 2.1 Equipment Weights................................................................................2-4 2.2 Equipment Electrical Hazards ..............................................................2-5 2.3 Equipment Heat Hazards......................................................................2-5 3 Turbine Architecture...........................................................................................3-1 4 System Component Descriptions......................................................................4-1 4.1 Major System Functions........................................................................4-1 4.2 General System Information.................................................................4-2 4.3 Blades And Rotor...................................................................................4-2 4.4 Drivetrain................................................................................................4-3 5 Descriptions of Turbine States............................................................................5-1 5.1 Initialization............................................................................................5-2 5.2 Off ...........................................................................................................5-2 5.3 Rotor Stopped........................................................................................5-2 5.4 System Test.............................................................................................5-3 5.5 Wait.........................................................................................................5-3 5.6 Motor ......................................................................................................5-4 Introduction Northwind 100 Wind Turbine 1-5 5.7 Ready.....................................................................................................5-4 5.8 Active.....................................................................................................5-4 5.9 Deceleration..........................................................................................5-5 5.10 Service..................................................................................................5-5 5.11 Yaw State Machine .............................................................................5-8 6 System Control-user interface...........................................................................6-1 6.1 Base Junction Box User Interface.........................................................6-1 6.2 Uptower Power Controller Interface ....................................................6-4 6.3 SmartView® Monitoring System...........................................................6-6 7 Operations ..........................................................................................................7-8 7.1 Starting Up..............................................................................................7-8 7.2 Shutting Down........................................................................................7-8 7.3 Alarms ....................................................................................................7-9 7.4 Service Operation ...............................................................................7-10 7.5 Fail-safe Operation (Protection Features).........................................7-11 8 Maintenance ......................................................................................................8-1 8.1 Service State..........................................................................................8-1 8.2 Electrical Lockout/Tag out Procedures ...............................................8-2 8.3 Motion Locks..........................................................................................8-3 8.4 Fall Restraint System..............................................................................8-6 8.5 Rotor Service..........................................................................................8-7 8.6 Main Shaft Service.................................................................................8-9 8.7 Mainframe/Rearframe........................................................................8-10 8.8 Check Subsystems..............................................................................8-11 8.9 Yaw System..........................................................................................8-12 8.10 Mechanical Brake System................................................................8-17 Introduction Northwind 100 Wind Turbine 1-6 8.11 Bolted Connections...........................................................................8-19 8.12 Nacelle...............................................................................................8-19 8.13 Electrical systems ..............................................................................8-20 8.14 Brake Pad Replacement Procedure................................................8-22 8.15 Northwind® 100 Maintenance Checklists & Bolt Torque Table......8-45 9 Troubleshooting..................................................................................................9-1 10 Drawings and Diagrams ..................................................................................10-1 10.1 Electrical Drawings and Diagrams...................................................10-1 10.2 Mechanical Drawings and Diagrams..............................................10-1 10.3 General Drawings and Diagrams.....................................................10-1 10.4 Vendor Documentation....................................................................10-3 Introduction Northwind 100 Wind Turbine 1-7 1.5 TYPOGRAPHICAL CONVENTIONS This manual uses the following typographical conventions. Table 1- Typographical conventions Element Convention Example Drawing Italicized names of drawings provided by Northern Power 1000119 Buttons In quotation marks ‘Auto’ 1.6 GETTING HELP If you have problems operating your Northwind® 100, follow these steps: See Appendix A for Troubleshooting details. Many system details are covered in this section. See Appendix B for Drawings and Diagrams as well as Vendor Documentation. Contact us at: Northern Power 29 Pitman Road Barre, VT 05641 Tel: 802.461.2955, Fax: 802.461.2953 Web: http://www.northernpower.com If you have comments, suggestions or questions about this manual, email us at customercare@northernpower.com Introduction Northwind 100 Wind Turbine 2-1 2 SAFETY INFORMATION The following is a list of safety definitions and symbols noted throughout the manual and/or located on the Northwind100 Wind Turbine. Safety symbols in the manual appear in the left-hand column. The corresponding text appears to the right. Refer to the Northwind® 100 Safe Operating Procedures for additional safety information. Table 2: Safety definitions and symbols Symbol Definition DANGER indicates an imminently hazardous situation, which, if not avoided, will result in death or serious injury. WARNING indicates a potentially hazardous situation, which, if not avoided, could result in death or serious injury. CAUTION indicates a potentially hazardous situation, which, if not avoided, may result in minor or moderate injury. Statements used for stating instructions or for the protection of personnel or property. This statement indicates that there is a potentially hazardous situation that, if not avoided, may result in damage to the equipment. This symbol indicates a potential electrical hazard. Introduction Northwind 100 Wind Turbine 2-2 This symbol indicates a potential pinching hazard. This symbol indicates a potential burning hazard. This symbol indicates that safety glasses are required. This symbol indicates a loud noise hazard and that hearing protection must be worn. This symbol indicates that protective gloves must be worn. This symbol indicates a potential crushing hazard from moving parts. This symbol indicates a crush hazard from above. This symbol indicates a chemical hazard. This symbol indicates a burn hazard from hot surfaces. Proper precautions must be followed by anyone operating, opening or servicing the equipment. Operators and maintenance personnel must follow all safety instructions found in this manual. Read the maintenance section and vendor documentation for specific warnings related to individual system components Introduction Northwind 100 Wind Turbine 2-3 Introduction Northwind 100 Wind Turbine 2-4 2.1 EQUIPMENT WEIGHTS When following safety precautions in this manual, the following equipment weights apply. Table 3- Equipment weights Equipment Mass (kg) Blade 370 Hub 280 Generator 2,890 Brake Disk 90 Mainframe 1480 Brake Caliper 225 Yaw System 310 Uptower Electrical 450 Rotor 1400 Tower – 37 m ~13,000 Downtower Cabinet 50 Tower Cables 180 Total Turbine System ~20,500 Introduction Northwind 100 Wind Turbine 2-5 2.2 EQUIPMENT ELECTRICAL HAZARDS When following safety precautions in this manual, the following equipment electrical hazards apply. Table 4- Equipment electrical hazards Equipment Maximum voltage DC generation Converter DC bus voltage: 900 VDC max, 780 VDC nominal DC energy storage DC bus during operation = 4.5 kJ reduces to under 20 J (50V) in 10 minutes following shutdown (in less than 1 second with discharge mode operating). Always check with a meter before touching DC bus components. AC distribution 480 VAC +10%, 120 VAC +10% Control system 120 VAC +10%, 24 VDC + 10% 2.3 EQUIPMENT HEAT HAZARDS When following safety precautions in this manual, the following equipment heat specifications apply. Table 5- Equipment heat hazards Equipment Maximum temperature Generator housing ~110º C (following full-power operation) Controller — converter filter inductors ~85º C Note: Give at least 15 minutes for cool down following full-power operation before working inside controller. Introduction Northwind 100 Wind Turbine 2-6 Controller — brake resistor case ~150º C, following shutdown. Cools off rapidly but use care when working in the vicinity Introduction Northwind 100 Wind Turbine 3-1 3 TURBINE ARCHITECTURE The Northwind® 100 wind turbine has the following components: Three bladed, stall controlled, upwind rotor with rigid hub Direct drive permanent magnet synchronous generator IGBT-based full power converter allowing variable speed generator operation and compliance with the UL 1741 utility interconnection standard Redundant rotor braking: dual mechanical brakes plus an electrodynamic brake System controller and power converter located in nacelle Active yaw drive system with friction damping Steel tube monopole tower An exploded view of the Northwind® 100 wind turbine Figure 3-1 - Northwind 100 Turbine Components Tower Service Platform Power Converter & System Controller Nacelle Cover Optional Obstruction Blade Generator Rotor Hub Mechanical Brake (behind generator) Meteorologic al Instruments (“Met Mast”) Mainframe Yaw Assembly (below) Operations Northwind 100 Wind Turbine- Operation 4-1 4 SYSTEM COMPONENT DESCRIPTIONS 4.1 MAJOR SYSTEM FUNCTIONS The ROTOR converts the aerodynamic energy in the wind to mechanical shaft torque. It also provides a lightning path from the blade tips to the main shaft. The GENERATOR converts the mechanical shaft power to electrical power at variable frequency, and provides the reaction torque to the rotor. The POWER CONVERTER converts the variable frequency generator output to constant frequency for feeding into the grid. The SYSTEM CONTROLLER manages the normal operation of the wind turbine. The system controller is integrated into the power converter cabinet. The YAW SYSTEM orients the turbine into the wind. The BRAKE SYSTEM slows the rotor. The PROTECTION SYSTEM is activated when the machine exceeds its normal operating limits, and takes the machine to a safe state. The NACELLE is an aggregate of several subsystems that include: The mainframe subsystem carries the mechanical rotor loads to the yaw system The yaw subsystem orients the machine into the wind and transfers mechanical loads to the tower. The nacelle cover protects the interior components (brake system, converter, yaw drive, etc) The met mast collects wind data for turbine control and monitoring The TOWER holds the machine up high in the wind stream and brings the mechanical loads to the foundation The TRANSFORMER converts the converter output voltage to grid voltage. The FOUNDATION transmits the tower base loads to the earth, and provides a path (conduit) for the electrical service, and contains features to accomplish system grounding. Operations Northwind 100 Wind Turbine- Operation 4-2 4.2 GENERAL SYSTEM INFORMATION Refer to Northwind® 100 General Specification A00281 4.3 BLADES AND ROTOR The fixed-pitch fiberglass reinforced plastic (FRP) blades capture the wind and turn the rotor shaft. The blade has an advanced root design, which is suitable for low temperature operation, and integral lightning protection is provided. The rotor hub is a Y-shaped design with an integral shaft mounting flange. The material is a ductile iron casting. The blade bolt holes are slotted to allow for setting pitch correctly at installation. Power limiting and control is achieved using an advanced stall control technology. In a stall controlled turbine, the captured power is a complex function of the blade design, wind speed and rotor speed. The Northwind® 100 regulates the generator speed by using the power converter to control current in the generator, which translates to torque on the generator rotor. This torque is regulated to balance the torque applied by the wind. The resulting energy is exported to the grid. Operations Northwind 100 Wind Turbine- Operation 4-3 4.4 DRIVETRAIN Table 6- Drivetrain specifications Tilt Angle 5° Generator Type Synchronous Permanent Magnet Generator Speed 60.0 RPM (Rated) Generator Rating 106 kW Continuous 200° (C) Class Insulation Main shaft Brakes 2 Spring applied, electrically released caliper brakes for E-Stop, Parking Hub Height 37m Maintenance Provisions Rotor, Generator, and Rearframe service crane; (optional) 500 lb. Service Hoist (optional) Nacelle One-piece fiberglass Removable port side hatch for service Removable transparent roof slot cover for service crane use 4.4.1 MAIN SHAFT BRAKE ASSEMBLY The Northwind® 100 uses a main shaft braking system consisting of two caliper brakes which can be motor-applied for normal braking and are fail safe (spring- applied) in emergency conditions. The braking system is readily serviced from within the nacelle. The two spring-applied, electro-mechanically released calipers are powered by 24 VDC. They act on a 0.7 m brake disk mounted on the rear of the mainshaft. In addition to the two mechanical brakes, the turbine includes an electrodynamic brake that is incorporated into the power converter. The turbine Operations Northwind 100 Wind Turbine- Operation 4-4 may be stopped under any circumstance by using any two of the three braking systems (i.e., one of the mechanical brakes and the electrodynamic brake or both mechanical brakes). Operations Northwind 100 Wind Turbine- Operation 4-5 4.4.2 GENERATOR ASSEMBLY The generator is an advanced permanent magnet generator with passive air- cooling via the exposed generator housing. The generator housing contains the bearing mounts for the generator mainshaft, which serves as the rotor mainshaft in this integrated design configuration. The generator includes an automatic bearing greasing system which allows for extended service intervals. When the greasing system requires service, it is readily performed from within the nacelle. The generator is sealed at the factory and should not be opened for any reason. Figure 4-1 - Generator Assembly 4.4.2.1 CAST GENERATOR HOUSING The stator assembly is mounted into a cast generator housing, The generator housing also contains the front bearing mounts for the generator mainshaft, which serves as the rotor mainshaft in this integrated design configuration. The generator housing and shaft assembly are designed to transfer all turbine loads to the mainframe without affecting the generator operating clearances. The cast generator housing has fins around the circumference to air cool the generator housing and the integral stator assembly. 4.4.2.2 CAST REAR GENERATOR HOUSING A cast rear generator housing shields the rear side of the generator, and provides mounting areas for the mechanical brakes. The rear generator housing contains the rear bearing for the mainshaft. The generator temperature monitoring sensors and the power cables exit through this cover. Operations Northwind 100 Wind Turbine- Operation 4-6 4.4.3 MAINFRAME The Northwind® 100 mainframe is the main structural element of the tower top assembly, transmitting the rotor loads from the main shaft and bearings to the tower. The mainframe includes external service platforms for access to the rotor hub and blades. The yaw drive system is mounted into the mainframe. Other accessories such as the fire extinguisher and the optional emergency light are mounted to the inside of this frame. 4.4.4 REARFRAME The Northwind® 100 rearframe is the assembly bolted to the rear of the mainframe (opposite the generator). It supports the Power Controls Assembly (PCA) as well as the nacelle fiberglass cover. A hatch is built into the floor to assist with service operations. Ductwork is built into the floor of the rearframe beneath the PCA mounts to channel hot air from the PCA out of the nacelle. 4.4.5 NACELLE ASSEMBLY The Northwind® 100 nacelle consists of a one-piece fiberglass enclosure bolted directly to the main and rear frames. A side hatch makes possible all service operations that cannot be carried out entirely within the nacelle. A clear port in the roof can be removed for service crane operations. The nacelle is sized so that it can be shipped, fully assembled, in a standard height ISO container. A rectangular steel plate bolts to the top of the assembly and provides a mounting location for the lightning rod and the aircraft warning lights (if equipped). 4.4.6 METEOROLOGICAL MAST Mounted off of the side of the nacelle is the meteorological mast which contains the meteorological instruments that measure the wind speed and yaw error. An optional obstruction light (FAA Light) is also mounted on the nacelle’s top. Operations Northwind 100 Wind Turbine- Operation 4-7 4.4.7 YAW ASSEMBLY Table 7- Yaw Assembly Specifications General Actively Driven, Slew Bearing, Friction Damping System Yaw Drive Electrically Driven Planetary Gearbox The Northwind® 100 uses an active yaw drive system to orient the turbine into the wind. A gear motor mounted to the turbine bedplate drives against the integral bull gear and slew ring which is attached to the tower in order to yaw the turbine. A wind azimuth sensor mounted on the nacelle provides the yaw command input. A friction system provides constant yaw friction to minimize low amplitude vibration of the nacelle. 4.4.8 POWER CONVERTER AND CONTROLS ASSEMBLY (PCA) The Northwind® 100 PCA manages all aspects of turbine operation. These tasks include environmental control, safety system operation, fault monitoring, and remote access. In addition, the PCA houses the power converter that allows the direct drive generator to supply power to the utility grid. The main System Control Board (SCB) is comprised of two subsystems; a Digital Signal Processor (DSP), which handles the operation of the power converter, while the balance of turbine controls are handled on a separate microprocessor. The single line diagram of the overall turbine electrical system is referenced in Appendix B- Drawings and Diagrams. The input section (rectifier) converts the AC output of the generator into DC energy, stored in the DC bus. The inverter then synthesizes AC sine wave current and passes power to the utility grid. The rectifier controls generator speed by modulating the electrical torque produced by the generator such that it equals the torque created by the blades and the wind. When the wind exceeds the cut-in threshold for the turbine, power begins to flow through the generator, converter, and into the grid. The dynamic brake subsystem serves two purposes; it applies load to the turbine for use as a braking system, and it functions as a DC bus voltage limiter during transient conditions such as high wind gusts or converter faults, thereby protecting the power converter from high voltage events. Operations Northwind 100 Wind Turbine- Operation 4-8 The controller is housed in a shock mounted UL508 compliant enclosure in the rear of the turbine nacelle. The power converter is an open frame device that mounts in the controller enclosure. The power converter is interfaced to and receives operating commands from SCB and its interface board. The unit is designed to comply with IEEE 519 and uses air-cooled IGBT switching devices. The Northwind® 100 comes factory set with a unity power factor output, but can be programmed to supply positive or negative reactive power to the utility power system. The supplied reactive power is the summation of a fixed VAR command and a power factor command. VAR Command enables the operator to command reactive power directly by adjusting a reactive power set point in the range from –45 kVAR to +45 kVAR (at rated voltage). This method allows the operator to set the reactive power flow independently of active power output. This reactive power is available as long as the turbine is connected to an active grid and is independent of the wind level. Power Factor Command enables the operator to command VARs based on the active power output by adjusting a power factor set point in the range from 0.90 lagging to 0.90 leading. This method allows the operator to set the reactive power flow as a fixed percentage of active power output. When the VAR Command portion is zero, this command produces a constant power factor. The main controller is equipped with hard switches to allow safe service mode access to the nacelle as well as manual yaw and brake control. Latching emergency stop buttons are located downtower on the base box door and uptower on the PCA. The base junction box houses a minimal set of controls that can be used to start and stop the machine, as well as trigger an emergency stop should the need arise. The tower lights are also controlled from this location. Remote access is via Ethernet (fiber optic, category 5, or wireless, depending on site layout) to the remote PC operating Northern Power’s remote access and control software, SmartView. Because of this double conversion process, adding a Northwind® 100 turbine to the grid is different than adding a traditional wind turbine in this power class because the power converter isolates the generator from the grid. Traditionally, wind turbines are directly-connected induction generators which require utility coordination due to their reactive current needs and large fault current Operations Northwind 100 Wind Turbine- Operation 4-9 characteristics. To the grid, the Northwind® 100 appears as an inverter, with no reactive current requirements and a very small fault current characteristic. The Northwind® 100 is designed to meet the UL 1741 grid interconnection standard. Operations Northwind 100 Wind Turbine- Operation 4-10 4.4.9 TOWER The standard Northwind® 100 tower is a multi-section, tapered tubular steel tower. Access is gained through a door located at the tower base. An electrical junction box that contains the power and control connection points; a fused, lockable power disconnect and a basic control interface to secure the turbine for service, is installed in the tower base. Access to the nacelle is provided by an internal ladder equipped with a fall restraint system. Decks are located within the tower slightly below each joint to simplify service and assembly operations. 4.4.10FOUNDATION The foundation for the Northwind® 100 typically falls into two broad categories: concrete pad or pile type. The foundation design is site specific to accommodate varying soil conditions and other factors. The customer must provide a foundation design based on loads and key dimensions provided by Northern. 4.4.11TRANSFORMER One transformer per Northwind® 100 is required for connecting the turbine with the utility system. This transformer is used to match the Northwind® 100 output voltage to the local utility voltage and to manage the safety and power quality of the electrical interface. This transformer is typically located adjacent to the tower base on a concrete pad although site conditions sometimes dictate other solutions/locations. Refer to the Northwind® 100 Application Requirements document, A00298, and the Protective Relay Specification, A00293, for further details. Operations Northwind 100 Wind Turbine- Operation 5-1 5 DESCRIPTIONS OF TURBINE STATES The Northwind® 100 is controlled through a sequence of state changes designed to ensure safe turbine operation. State descriptions and requirements for changing states are outlined as follows: Table 8- State Definitions Turbine State Rectifier Inverter Brakes Initialization Off Off Applied Off Off Off Applied Rotor Stopped Off As requested Applied System Test Off/Test Active Applied/Test Wait Off As required Released Motor Motoring Active Released Ready Ready As required Released Active Active Active Released Decelerate Active Active Generator torque & motor applied mech. brakes; solenoid apply brakes if necessary Service Disabled Disabled Manual controls Note: Inverter “As requested” or “As required” - Inverter may be Ready or Active. The Active state may be required by VAR (reactive power) support functions. Operations Northwind 100 Wind Turbine- Operation 5-2 5.1 INITIALIZATION The turbine enters Initialization on power up. The controller will transition to OFF after boot up is complete. The initialization takes approximately 90 seconds. 5.2 OFF In the OFF state, the turbine controller is operating, but the power converter is offline and the rotor brakes are applied. The yaw system is operational and will track the wind if the wind speed is above ~3 m/s. If all external conditions are correct (turbine is enabled, Run/Stop/Service switch is in the Run position, up-tower Run/Stop switch is in Run position, no Inverter faults) the controller will transition to the Rotor Stopped state. If the base Run/Stop/Service switch is in the Service position and/or the up-tower Run/Stop switch is in Stop, the controller will transition to the Service state. 5.3 ROTOR STOPPED In the Rotor Stopped state, the brakes are applied but the Inverter is available to provide reactive power support (VAR support) if requested. The yaw system is operational and will track the wind if the wind speed is above ~3 m/s. If all conditions are met to allow the turbine to operate (environmental conditions are within range, state timers have elapsed, faults are clear, etc) the turbine will transition to the System Test state after a minimum of 5 minutes. The turbine may remain in this state if environmental conditions prohibit operation (such as wind speed is too high, or outside air temperature is too low). If external enables (HMI, Dispatch, or Run switches) are removed, or an inverter fault occurs, the turbine will transition to the OFF state. Operations Northwind 100 Wind Turbine- Operation 5-3 5.4 SYSTEM TEST The System Test state is setup to allow the turbine to perform several self tests. They may or may not be used on a given turbine based on the software configuration. These tests may include: DC Bus Limiter check – This is a test to verify that the DC Bus limiter circuit is working correctly, and the discharge resistor is present. During the test, the inverter will be activated for several seconds, and a small amount of power will be discharged into the resistor. Mechanical brake check – This test is used to verify that a mechanical brake is producing at least the minimum amount of required torque. It is performed on one brake each time the test happens. The system alternates between the A and B brake on subsequent tests. Following successful completion of all configured tests, the controller will transition to the Wait state. If any test fails, the system will transition to the Decelerate state and the appropriate faults will be displayed on the HMI. 5.5 WAIT The Wait state is the start-up state of the turbine where the turbine is waiting for enough wind to operate. The rotor is free to rotate (mechanical brakes released) and the DC bus is charged. The Inverter is available to provide reactive power support (VAR support) if requested. If enough wind is available to overcome the startup torque requirements, the turbine will begin to rotate on its own. Once the rotor speed exceeds the proper set point, the turbine will transition to the Ready state. If there is enough wind to make power, but not enough to overcome the startup torque requirements, the turbine will transition to the Motor state. If external enables (HMI, Dispatch, or ‘Run’ switches) are removed, or a fault occurs, the turbine will transition to the Decelerate state. Operations Northwind 100 Wind Turbine- Operation 5-4 5.6 MOTOR In the Motor state, the rectifier feeds power into the generator, accelerating the rotor. After reaching a target speed, the rotor is released to free spin and the turbine transitions to the Ready state. The Inverter is active during motoring to support the DC bus. If external enables (HMI, Dispatch, or Run switches) are removed, or a fault occurs, the turbine will transition to the Decelerate state. 5.7 READY In the Ready state, the rotor is spinning, but not at a high enough rate to make power. The Inverter is available to provide reactive power support (VAR support) if requested. If the rotor accelerates (due to wind) and surpasses the cut-in threshold, the turbine will transition to the Active state. If the wind dies off and the rotor slows, the turbine will return to the Wait state. If external enables (HMI, Dispatch, or Run switches) are removed, or a fault occurs, the turbine will transition to the Decelerate state. 5.8 ACTIVE The Active state is the power producing mode of the turbine. In this state, the Rectifier and Inverter are both active, and are working with the generator to extract energy from the wind. As the wind increases, the power flow into the grid increases. The rectifier controls the speed of the generator based on predetermined optimum rotor speed vs. wind speed relationship. The inverter precisely maintains DC bus voltage by varying output current to the grid. If the wind dies down and the rotor slows, the turbine will transition back to the Ready state. If external enables (HMI, Dispatch, or Run switches) are removed, or a fault occurs, the turbine will transition to the Decelerate state. Operations Northwind 100 Wind Turbine- Operation 5-5 5.9 DECELERATION The Deceleration state is used to slow the rotor to a stop by whatever means are necessary. If the Rectifier and DC Bus limiter are available (i.e. not faulted), the turbine will generally first apply the dynamic brake (electrical braking with the generator). The mechanical brakes are driven closed, but do not act until after the rectifier has already slowed the machine. The Inverter will continue to supply power to the grid if available. If the Rectifier and Bus limiter are not available, or the turbine needs to be stopped immediately, the mechanical brakes will apply quickly (magnets release so the brakes are spring applied rapidly). In the case of an E-Stop, if the Rectifier and Bus limiter are available, they will contribute as necessary, while at the same time the mechanical brakes will apply rapidly, resulting in a very fast stop. When the rotor is stopped, and the mechanical brakes are fully applied, the turbine will transition to the Rotor Stopped state, unless an Inverter fault is present, in which case the turbine will transition to the OFF state. 5.10 SERVICE The Service state is used for when personnel are near or within the turbine. Placing the base Run/Stop/Service switch into the Service position, or placing the nacelle Run/Stop switch into the Stop position will cause the turbine to transition to the Service state. However, the Service state functions will not be available unless both switches are in the appropriate positions. In the Service state, the turbine will not automatically yaw. There is a yaw control switch in the nacelle that is functional in service mode, and can be used to assist with maintenance tasks. The mechanical brakes will be applied on entrance to the Service state, but may be manually controlled from the nacelle. There is a control switch for each brake, which allows them to be released independently. Placing the base Run/Stop/Service switch into the Run position, and placing the nacelle Run/Stop switch into the Run position will allow the turbine to resume normal operation. Operations Northwind 100 Wind Turbine- Operation 5-6 State Transition Diagram Note: All speed values (wR = rotor speed) shown are set points and are approximate. Figure 5-1 - NW100B Turbine Control State Diagram Operations Northwind 100 Wind Turbine- Operation 5-7 Figure 5-2 - Inverter Control State Diagram Operations Northwind 100 Wind Turbine- Operation 5-8 5.11 YAW STATE MACHINE The yaw system runs virtually independently from the turbine state machine. If the turbine is free to operate, the yaw controller is also free to operate. If the turbine is placed into service mode, an E-Stop is pressed, or there is a yaw system fault, the yaw controller will cease automatic operation. The yaw system will also be disabled anytime the wind speed drops very low (since the wind vane is no longer accurate). During normal operation, the turbine is in the AutoYaw Enabled state. If the wind vane indicates the turbine is more than 5 degrees off the wind axis (after a time delay), then the controller changes to the appropriate state to move the turbine towards the correct wind direction (yawing Left or yawing Right). The yaw system also constantly tracks the turbine position. This information is used to monitor the number of cable wraps in the tower. During the course of normal operation, the tower cable will gradually accumulate twists. When the number or turns exceeds 4 in either direction, the controller takes notice: If turn count is higher than 4 and the turbine is not making power, the brakes will apply (turbine transitions to Rotor Stopped state) and the turbine will unwind. After unwinding, the turbine will be allowed to restart. If the turn count reaches 5, the turbine will transition to Rotor Stopped state (regardless of power production), unwind, and then be allowed to restart. When the turbine is placed into the Service state, the yaw system is disabled. The Yaw switch in the nacelle can be used to yaw the machine ‘Left’ or ‘Right’. The turn count limit will still apply; it will not be possible to yaw past 5 turns in either direction. Operations Northwind 100 Wind Turbine- Operation 5-9 Auto Yaw Disabled Yawing Left Auto Yaw Enabled Yawing Right Shutting DownUnwinding Left Unwinding Right Figure 5-3 - Yaw State Diagram Operations Northwind 100 Wind Turbine- Operation 6-1 6 SYSTEM CONTROL-USER INTERFACE There are two user interfaces for the Northwind® 100: The Base Junction Box Interface Uptower Controls Cabinet Interface The interfaces are described in detail in the following sections. The Northwind® 100 is also provided with a PC-based data acquisition and human-machine interface (HMI) application called SmartView®. 6.1 BASE JUNCTION BOX USER INTERFACE Figure 6-1 - Base Junction Box Interface Diagram Operations Northwind 100 Wind Turbine- Operation 6-2 Table 9- Base Junction Box Interface Element Descriptions Element Type Description Do Not Climb Light Illuminates red when the turbine is not in Service mode. Do not climb the tower when this light is illuminated. Emergency Stop Latching push-button The “pressed” position causes the mechanical brakes to apply with full torque and the electro-dynamic brake to apply, initiating a fast shutdown of the turbine (if running). An E-stop fault will also be latched in the controller. Pulling on the button (clockwise twist on some models) changes the switch position from “pressed” to “released,” however the turbine will not run until the E-Stop fault is cleared. This fault will need to be reset at the uptower interface, or using the SmartView HMI. Run/Stop/Service Switch Three- position switch Placing this switch in Run Mode will allow the turbine to go online after any faults are cleared. The Stop position will cause the turbine to come to a halt but will not prevent the turbine from yawing into the wind. If Service mode is selected while the turbine is running, the turbine will perform a “normal” shut down, then go to Service mode, which will prevent the turbine from starting and will prevent the turbine from yawing. This provides the safety required to allow the tower to be climbed. Tower Light Two-position switch Placing this switch in the upward position will turn on the tower lights. Placing this switch in the lower position will turn off the tower lights. Main Disconnect (DX01) Two-position switch This is the main disconnect which de- energizes all of the electrical systems in the nacelle and some of the electrical systems Operations Northwind 100 Wind Turbine- Operation 6-3 Element Type Description in the base junction box. The handle must be in the OFF position to access the inside of the base junction box. Operations Northwind 100 Wind Turbine- Operation 6-4 6.2 UPTOWER POWER CONTROLLER INTERFACE Figure 6-2 - Uptower Controller Interface Diagram Operations Northwind 100 Wind Turbine- Operation 6-5 Table 10-Uptower Controller Interface Element Descriptions Element Type Description Emergency Stop Latching push-button The “pressed” position causes the mechanical brakes to apply with full torque and the electro-dynamic brake to apply, initiating a fast shutdown of the turbine (if running). An E-stop fault will also be latched in the controller. Pulling on the button (clockwise twist on some models) changes the switch position from “pressed” to “released,” however, the turbine will not run until the E-Stop fault is cleared. System Ready Light Illuminates green when all E-Stop buttons are in the “released” position, the mechanical brake is applied, and the Service switch is in Run Mode (Base Service switch is in ‘Service’), indicating the turbine is ready to return to automatic operation (after the Base Service switch is returned to Run Mode). Turbine On- line Light Illuminates green when Turbine is operating (online/active) Fault Light Illuminates red when a turbine fault condition is present or has occurred. Yaw Control Three- position, spring-return switch If the turbine is in Service mode, turning this switch to Left or Right will manually yaw the turbine in the corresponding direction for the duration that the switch is held in that position. Releasing the switch will stop the turbine from yawing.(Will not function if E-Stop is pressed or a Yaw Fault is active) Turbine Run Two-position switch Placing this switch in Run Mode will allow the turbine to go on line after any faults are cleared. If Service Mode is selected while the turbine is running, the turbine will perform a “normal” shut down, then go to Service mode, which will prevent the turbine from starting while service is being performed. If the turbine is not running, it will just transition to Service mode. Fault Reset Momentary If the turbine is faulted, pressing this button will clear all Operations Northwind 100 Wind Turbine- Operation 6-6 Element Type Description push-button the faults if all fault conditions have cleared. If any fault conditions are active, those faults will not be cleared and the turbine will remain in a faulted state. Brake A Three- position switch Controls Brake A while in Service mode. Full position – applies Brake A with full torque Normal position – applies Brake A with reduced torque Released position – releases Brake A Brake B Three- position switch Controls Brake B while in Service mode. Positions are the same as the Brake A switch Nacelle Light Two-position switch Placing this switch in the upward position will turn on the nacelle lights if the downtower Run/Stop/Service switch is in the Service position. Placing this switch in the lower position will turn off the nacelle lights. This switch is independent of the tower light switch located on the base junction box. 6.3 SMARTVIEW® MONITORING SYSTEM The SmartView®Monitoring System provides a robust graphical interface to the Northwind® 100. It is an integrated system of software running on a separate computer, called the Remote Terminal Unit (RTU). The RTU is connected to the Northwind® 100 using an Ethernet network and continuously polls selected memory locations in the controller. SmartView also provides a way to change control set points and remotely enable or shut down the Northwind® 100. The SmartView®Monitoring System can provide a Human Machine Interface (HMI) near the location of the wind turbines (called a local HMI) or remotely using the Internet with a web browser (called a web HMI). The SmartView ®system continuously logs important operational data into a database, and makes that data available to a SmartView® HMI application (local or web) or to any 3rd party application that can communicate with a database using the Open Database Connectivity (ODBC) standard. By connecting to SmartView’s database, a user can view real time data, alarms, events, and trends. Additionally, SmartView® can actively notify an operator of Operations Northwind 100 Wind Turbine- Operation 6-7 trouble by sending an email notification to one or more users for any defined alarm or event. Operations Northwind 100 Wind Turbine- Operation 7-8 7 OPERATIONS This section describes how to operate the Northwind® 100 and includes information on starting up and shutting down the turbine and provides information on alarms. 7.1 STARTING UP For the turbine to automatically start up, the following conditions must be true: All Emergency Stop buttons must be released All faults need to be clear, this may require a Fault Reset from the SmartView computer The Service Switches on the Base Junction Box Interface and the Uptower Controller Interface must be in the ‘Run’ position. If installed, the customer controlled Run/Stop contact must be in the Run position. The software enables must be on: HMI Enable Dispatch Enable When all faults have cleared for a preset amount of time, the turbine will begin automatic operation. In this mode, the turbine will operate when wind is present, and will shut itself down should conditions not be conducive to operation. 7.2 SHUTTING DOWN If the turbine control system detects any problems during online operation, the turbine shuts down automatically. If the turbine needs to be shut down manually by an operator, placing the Service Switch in the ‘Service’ or ‘Stop’ position causes the turbine to perform a “normal” shutdown. See Section 7.4 for details on service operation. You may also shut down the turbine using SmartView. If a customer controlled Run/Stop contact is installed, this may also be used to initiate a shutdown. If the turbine needs to be shut down in an emergency, press the Emergency Stop button on any of the interfaces. Doing so causes the turbine to shut down as rapidly as possible. The mechanical brakes and the yaw drive are disabled Operations Northwind 100 Wind Turbine- Operation 7-9 following an Emergency Stop (the brakes will remain in the applied position). However, this type of shut down puts increased stress on the components of the turbine and should not be used to shut down the turbine in a non-emergency situation. 7.3 ALARMS There are four categories of alarms: turbine faults, environmental conditions, external alarms, and warnings. The first three categories cause the turbine to shut down. Turbine faults exist when something in the turbine is not behaving as it should. These faults may signify a failed component or a software error. Environmental conditions can shut the turbine down when it is too cold, too windy, too hot, etc. Typically these conditions will desist over time and the turbine will restart automatically. External alarms are typically driven by the customer interface, or someone in the tower pressing an E-Stop button. After the conditions are cleared, the turbine may need a Fault Reset command, either uptower or via the SmartView HMI. Fault resetting is possible at the Power Controller Interface (in the nacelle) or via the SmartView System. If a fault is currently active, the Turbine Fault light on the Controller Interface will be on. After all fault conditions have cleared, pressing the Fault Reset will clear all faults. Warnings notify the user of a potentially abnormal operating condition. Warnings do not cause the turbine to shutdown and therefore do not cause the Turbine Fault light to come on. Operations Northwind 100 Wind Turbine- Operation 7-10 7.4 SERVICE OPERATION The interfaces are designed to prevent any unsafe conditions while service is being performed. In the Service State, the turbine remains offline and the automatic yaw is disabled. While the mechanical brake is initially applied when entering Service State, manual operation of both the yaw system and mechanical brake systems is possible from the nacelle. Following is a procedure for entering service state and performing manual operations. 7.4.1 ENTERING SERVICE STATE Place the ‘Run/Stop/Service’ switch on the Base Junction Box Interface into the ‘Service’ position. This causes the turbine to perform a normal shutdown if it is running. If it is faulted, the turbine can still enter the Service state. 7.4.2 PERFORMING SERVICE IN THE NACELLE To perform service in the nacelle, first place the base ‘Run/Stop/Service’ switch in Service position. Upon entering the nacelle, place the nacelle ‘Run/Stop’ switch in the ‘Stop’ position in order to lock out restart via the base switch. When service is complete, return the nacelle ‘Run/Stop’ switch to the ‘Run’ position. If all E-stop buttons are released (base and nacelle), the Ready light will come on, indicating the turbine is ready for normal operation after the base ‘Run/Stop/Service’ switch is also returned to ‘Run’ mode. The base ‘Run/Stop/Service’ switch should always be placed in Service Mode before climbing the tower to prevent any automatic operation of the turbine that could be unsafe to the operator. A red ‘Do Not Climb’ light is provided on the Base Junction Box to indicate that the tower is not safe to climb (not in Service State) Operations Northwind 100 Wind Turbine- Operation 7-11 7.4.3 MANUALLY YAWING THE TURBINE FROM THE NACELLE CONTROLLER After the nacelle ‘Run/Stop’ switch is placed in the ‘Stop’ position, the turbine can be manually yawed using the 3-position, spring-return switch. Turning the switch to ‘Right’ and holding it causes the nacelle to turn clockwise (looking down on the turbine). Turning the switch to ‘Left’ and holding it causes the nacelle to turn counter-clockwise (looking down on the turbine). 7.4.4 MANUALLY OPERATING THE BRAKES FROM THE BRAKE CONTROLLER To release a mechanical brake, switch the appropriate switch to the ‘Released’ position (there is a switch for each mechanical brake). If the rotor speed exceeds 10 RPM in the Service state, the turbine will fault on over-speed and will perform a fast shutdown (i.e. full torque brake). CAUTION: Full torque brake operation is loud. Hearing protection should be worn. 7.5 FAIL-SAFE OPERATION (PROTECTION FEATURES) In case of component failure, the Northwind® 100 fails to a safe state. In addition, the microprocessor controller attempts to protect both the maintenance persons and the turbine in case of user error in the Service State. Detailed descriptions of the fail-safe protection features follow. 7.5.1 OVERSPEED PROTECTION During operation if the rotor speed exceeds the overspeed set point, the turbine faults and an E-stop is triggered. There are 2 overspeed settings, the main sensor setting is 60.9 rpm, and the backup sensor is 62.1 rpm. While in the Service State, the overspeed set point changes to 10 rpm, if the rotor reaches 10 rpm the turbine faults and an E-stop is triggered. If the mechanical brakes are accidentally released in Service state, AND the normal RPM sensor fails, the overspeed relay causes an E-Stop fault to occur, stopping the machine until the fault is reset. Operations Northwind 100 Wind Turbine- Operation 7-12 7.5.2 OPEN WIRE PROTECTION All E-Stop buttons are wired with contacts held closed in the non-E-Stop position and default to pressed behavior in case of wire failure. The Base and Nacelle Service switches default to Service Mode in case of wire failure. If the turbine is online, the machine shuts down normally. If the turbine is in Service, the machine remains in Service until the wire is fixed. The nacelle Yaw Control switch defaults to the middle (OFF) position in case of wire failure. Manual Yaw control remains inactive until the wire is fixed. The brake release switches default to brakes applied in case of wire failure. 7.5.3 EMERGENCY STOP An Emergency Stop is triggered either from a turbine fault, or by pressing one of the Emergency Stop buttons, one is located on the downtower junction box, and the other in the nacelle. 7.5.4 OTHER The manual yaw and brake operations can only be performed at the controller panel. No manual yaw or brake operation is possible from any remote HMI (SmartView or other). Maintenance Northwind 100 Wind Turbine- Maintenance 8-1 8 MAINTENANCE This section of the manual outlines the maintenance requirements for the Northwind 100 wind turbine. The Northwind® 100 is designed to provide highly reliable operation with minimal maintenance. Routine maintenance is required every twelve months. In addition, several longer term service items are suggested. These procedures are critical to ensure reliable turbine operation during its 20-year design life. Most routine maintenance tasks are to be carried out at a one-year service interval. Refer to the maintenance checklist in Section 8.15. Maintenance tasks that are not scheduled on a specific interval do not appear on the checklist, but their procedures are described in this section. A minimum of two qualified service persons is required to service the turbine. All service activities must be carried out in conjunction with relevant safe working procedures and codes. All personnel should first be familiarized with this document before performing any maintenance tasks on the turbine. Factory training is preferable. Do not service turbine below -20C/-4F. Some components are not designed to be handled/serviced below this temperature, though they are capable of operating correctly. 8.1 SERVICE STATE The Northwind®100 has a Service State that allows maintenance personnel to service the wind turbine. The Service State allows manual control of the mechanical brake system, yaw drive system, and power electronics devices to perform maintenance and testing of critical turbine components without initiating a start-up sequence. Unless otherwise stated, perform all maintenance only while the machine is in Service State. See Section 7.4 for procedures for entering and exiting Service State. Maintenance Northwind 100 Wind Turbine- Maintenance 8-2 8.2 ELECTRICAL LOCKOUT/TAG OUT PROCEDURES Lock out/tag out the Northwind® 100 before working inside any electrical enclosures, including: Base junction box (complete lockout required): Any nacelle wiring (base lockout OK) Power controls Cabinet Generator terminals Yaw drive To completely lock out and tag out the Northwind® 100: Shut down the turbine, using the ‘Run/Stop/Service’ switch or other means (HMI, etc). The rotor comes to a standstill and mechanical brakes are applied. De-energize and lock out/tag out the utility power upstream of the Northwind® 100, using any available devices/means at the site. On some sites this will require disconnecting power from the high side of the turbine isolation transformer. This removes power from all electrical systems within the Northwind® 100. You must do this to perform work inside the base grid power junction box cabinet. Verify that the circuit is de-energized with a multimeter before beginning work. To lock out and tag out the Northwind® 100 at the base of the tower: Shut down the turbine, using the ‘Run/Stop/Service’ switch or other means (HMI, etc). The rotor comes to a standstill and mechanical brakes are applied. Turn off, lock out, and tag out the main disconnect on the base junction box. This action de-energizes all electrical systems in the nacelle and some of the electrical systems inside the base junction box. Verify that the circuit is de-energized with a multimeter before beginning work. For electrical work inside the nacelle, do one of the following: Follow the lock out/tag out procedure for an external disconnect. At minimum, turn off, lock out, and tag out the main disconnect on the base junction box. This action de-energizes all electrical systems in the Maintenance Northwind 100 Wind Turbine- Maintenance 8-2 nacelle and some of the electrical systems inside the base junction box. If you only turn off, lock out and tag out the main disconnect in the base junction box, 480VAC, 120VAC, and 24VDC will still be present in the base junction box. Maintenance Northwind 100 Wind Turbine- Maintenance 8-3 8.3 MOTION LOCKS Mechanical means to prevent rotation are necessary when working on components that interface with these parts. The main components subject to this are the brakes and the yaw drive. 8.3.1 ROTOR LOCK The Northwind® 100 uses the redundant mechanical brakes for rotor locking purposes. If brake service is required, service one brake at a time and leave the other brake applied. This will prevent the technicians from being exposed to a rotating brake disc. If you need to work on a brake system, only release one brake at a time to ensure personnel safety around rotating parts. 8.3.2 BRAKE MAGNET LOCK A clamp is provided to lock one brake magnet in the “latched” (brake not applied) position. This prevents the brake from rapidly applying in the event of power loss or an E-Stop event. The clamp should only be applied during brake pad service and should be removed immediately thereafter. To lock a brake magnet: Remove plastic safety guard from brake housing Remove clamp from right brake arm using hex wrench Place clamp over magnet to be “latched” Tighten in place with hex wrench Brake “Fast Apply” is now disabled With the brake magnet lock installed, one brake will have a very slow response time. This will compromise the safety of the turbine if the lock is not removed at the end of service work and emergency braking is called for. Maintenance Northwind 100 Wind Turbine- Maintenance 8-4 Figure 8-1 - The Brake Magnet Lock To remove the Lock: Be sure brake is fully applied before removing clamp Loosen bolts with hex wrench, remove clamp and replace it on the right brake arm. Re-install plastic safety guard. 8.3.3 INSTALLING THE YAW LOCK PIN To lock the yaw system, insert the yaw lock pin: Place turbine in Service State. Locate the lock pin hole in the bedplate Drop yaw lock pin into space between gear teeth. Be careful to line up the cross section shape of the yaw lock pin properly with the shape of the gear teeth below. Maintenance Northwind 100 Wind Turbine- Maintenance 8-5 Figure 8-2 - The Lock Pin Hole Note:To remove the yaw lock pin, you may need to manually activate the yaw motor for a split second (yaw ‘LEFT’ or yaw ‘RIGHT’) to release the pressure on the pin. Figure 8-3 - Lock Pin Location Figure 8-4 - Lock Pin Insertion Lock pin hole Maintenance Northwind 100 Wind Turbine- Maintenance 8-6 8.4 FALL RESTRAINT SYSTEM Each harness should be inspected for wear. Any fraying straps or cracked hardware should be immediately disposed of. Each ascender should be checked for excessive wear or cracks. In general, if the integrity of any piece of the fall restraint system appears questionable, dispose of it immediately and procure a replacement. Also routinely check the tension of the ascender guide cable. Verify connections are tight at the top of the ladder. After all other checks are completed, working near the bottom of the ladder, hang full weight on the safety climb system to test integrity. Maintenance Northwind 100 Wind Turbine- Maintenance 8-7 8.5 ROTOR SERVICE This section describes the necessary maintenance tasks for the rotor. 8.5.1 VISUALLY INSPECT HUB AND BLADES Remove the nacelle hatch. Verify that you are securely fastened to at least one fall protection point. Climb onto and move along the maintenance platform to the front of the machine. Inspect hub and all three blade roots for cracks or surface discontinuities. Mark and date any cracks with a permanent marker. It will be necessary to turn the rotor to fully inspect the hub and blades. Stand clear of shaft, hub, and blades while rotor is turning. Stay clear of moving components while turning the rotor. Release both brakes using the operator controls in the nacelle. The rotor will turn, if there is adequate wind, up to a maximum of 10rpm. Rotate the rotor until the next section of the hub/blades is visible then re-apply the brakes using the operator controls. Repeat until all areas of the hub and blades have been inspected. Maintenance Northwind 100 Wind Turbine- Maintenance 8-8 8.5.2 INSPECT LIGHTNING PROTECTION SYSTEM Visually inspect the lightning plate and rod on the nacelle roof, and the grounding cables from end to end. Check that all connections are tight and free from corrosion. Verify spark gap tabs from hub to main bearing outer cover are intact and have not deformed. There should be a 2mm distance between the spark gap tab and the frame. The gap surfaces should also be clean and free of paint. Figure 8-5 - Lightning Rod, FAA Light, and Mounting Plate (Light and Rod position will be reversed on newer models). Maintenance Northwind 100 Wind Turbine- Maintenance 8-9 8.6 MAIN SHAFT SERVICE Visually inspect main shaft, look for any abnormalities (cracks, rub marks, etc.) In winds <10 m/s, release both brakes and allow turbine to spin. Listen for any uncommon noises (rubbing, scraping), re-apply brake 8.6.1 GENERATOR BEARING GREASE Generator internals do not need scheduled maintenance. Do not compromise the generator seals for any reason. To service the grease system: Remove old grease cartridges. Install new grease cartridges. Set grease cartridge timers to “12”, signifying a 12 month discharge time. Dispose of any grease that is expelled from the grease outlets into the catch can. Figure 8-6 - Greasing System Note: Use Mobil SHC 460 bearing grease only. Failure to do so may compromise the bearing longevity. Maintenance Northwind 100 Wind Turbine- Maintenance 8-10 8.7 MAINFRAME/REARFRAME This section describes the necessary maintenance tasks for the mainframe. 8.7.1 VISUALLY INSPECT MAINFRAME AND REARFRAME Check the entire mainframe and rearframe for any abnormalities, cracks, missing paint, or other discontinuities. Pay special attention to the inspection of the welds. 8.7.2 CHECK BOLTED JOINT Verify that the bolted mainframe to rearframe joint is tight. Check bolt torques according to the torque checklist. Figure 8-7 - Rearframe bolted joint Maintenance Northwind 100 Wind Turbine- Maintenance 8-11 8.8 CHECK SUBSYSTEMS Verify fire extinguisher is charged and in a functional state. Replace if discharged. Verify that the emergency light (if equipped) is functioning correctly by pressing the test button. Replace battery if hold-up time is insufficient to allow exit from the tower in power outage conditions. Verify the nacelle rope light is functional. Verify operation of the wind instrument heaters. Place a hand on the instruments to test for warmth, use caution as sensors may be very hot. Test the FAA light, (if installed) by covering the light sensor. Verify both lamps light after time delay. When inspecting or working on an FAA light, use the clip in point provided on the top of the nacelle. It is mounted to the rear of the nacelle lifting bar. Figure 8-8 - FAA Light Clip In Point FAA light service clip in point Maintenance Northwind 100 Wind Turbine- Maintenance 8-12 8.9 YAW SYSTEM This section describes the necessary maintenance tasks for the yaw system. 8.9.1 CHECK YAW DRIVE RESERVOIR OIL LEVEL Oil should be visible in both view ports on the side of the gearbox oil reservoir (if equipped) or through the view ports in the side of the gearbox (if not equipped with reservoir). Use Mobil Synthetic SHC 629 (or 630) to fill reservoir. The yaw gearbox lubricating oil requires replacement every 5 years; refer to the extended maintenance section. Figure 8-9 - Yaw Gearbox Oil Resevoir (if equipped) Maintenance Northwind 100 Wind Turbine- Maintenance 8-13 8.9.2 GREASE YAW BEARING Using a grease gun, pump one (1) tube (13 oz.) of Mobil SHC 460 grease into the yaw bearing’s 4 grease fittings (approx ¼ tube per fitting)while rotating the yaw system to ensure even filling of the bearing. The fittings are accessed from the ladder at the top of the tower. Wipe off excess grease from bearing surfaces. Figure 8-10 - Yaw Bearing Grease Fitting (Bearing Has Been Greased) 8.9.3 GREASE OPEN YAW GEARING Use caution while operating the yaw drive while applying gear face lubricant. To grease open yaw gearing: Remove access cover in the floor of the nacelle. Clean gear teeth using a clean rag and/or wire brush. Spray a small amount of open gear lubricant on all exposed gear teeth. If aerosol grease is not available, Mobil SHC 629 (or 630) may be brushed onto the gear teeth. Maintenance Northwind 100 Wind Turbine- Maintenance 8-14 Yaw turbine to reveal next portion of gear. Apply lubricant and continue process to grease all teeth with a light coating of lubricant. Avoid over-applying open gear lubricant as it will interfere with the yaw sensors. Figure 8-11 - Yaw Bearing Access Maintenance Northwind 100 Wind Turbine- Maintenance 8-15 8.9.4 CHECK/CHANGE YAW FRICTION PADS To check/change yaw friction pads: Loosen the M30 jam nut. Remove the M30 yaw brake tensioning bolt. Loosen and remove the two bolts that hold the yaw brake housing to the tower top. Carefully slide the yaw brake housing out. Use two hands so that the piston and spring stack do not fall out the bottom of the housing. Remove all brake dust. Replace friction pads if brake material thickness measures 1/4" or less or if surface is excessively deformed. Also replace pads if any squealing exists during yaw motion. Measure and record friction pad thickness if not replacing pads. Reinstall assembly, torque bolts to appropriate torque as indicated in the bolt torque table in Section 8.15. Repeat for each of the three yaw friction assemblies. Figure 8-12 - A Yaw Brake Friction Assembly Brake Housing F t Jam Nut Tensioning Bolt Maintenance Northwind 100 Wind Turbine- Maintenance 8-16 8.9.5 VERIFY YAW COUNT To verify yaw count: Verify that the number of twists in the cable is consistent with the number of twists indicated on the HMI. When initially installed, the multi- conductor cable is tie wrapped to the main tower cable with no twists. Therefore, a twist of the tower cable can be determined by counting how many times the signal cables wrap around the main cable. If there is a difference in the two yaw counts, manually yaw the machine so that there is no twist in the cable and the machine is pointed due North. When machine is aligned correctly, zero the yaw counts using the ServiceHMI software. Maintenance Northwind 100 Wind Turbine- Maintenance 8-17 8.10 MECHANICAL BRAKE SYSTEM This section describes the necessary maintenance tasks for the mechanical brake system. Please see the Brake Pad Replacement Procedure in Section 8.14 for additional information. Please see the Hanning and Kahl: Brake System Operations and Maintenance Manual referenced in Section 10.4, “Vendor Documentation” for additional information. 8.10.1CHECK PAD GAP The gap between the pads and the brake disk should be 1mm on the fixed side and 1.5 – 2.0 mm on the floating side. 8.10.2CHECK PAD CONDITION Pads must be tear, groove, and fracture free 8.10.3CHECK SIGNALS ON CONTROLLER Simulate the pad wear signal by unplugging the pad wear circuit at one of the brake pads. The pad wear fault should show up on the Service HMI or SmartView screen. Perform test on both brakes. Maintenance Northwind 100 Wind Turbine- Maintenance 8-18 Figure 8-13 - Pad Wear Connectors Pad wear circuit Maintenance Northwind 100 Wind Turbine- Maintenance 8-19 8.11 BOLTED CONNECTIONS This section describes the necessary maintenance tasks for bolts. 8.11.1CHECK TORQUE Check torque on bolts in each connection. Refer to Bolt Torque Check Table in the Maintenance section for the quantity of bolts to check in each joint, as well as the check torque setting. Use a calibrated torque wrench for all tests. If any bolt turns when you check it, tighten it to specification (not the check value, which is typically 90% of the specification) and make a note on the checklist. Then check all remaining bolts in connection. Torque the bolt from the nut side of the connection whenever possible. Note:If for any reason you must replace a bolt, be sure to apply anti- seize to the threads and between the nut and the washer. 8.12 NACELLE This section describes the necessary maintenance tasks for the nacelle. 8.12.1INSPECT NACELLE To inspect nacelle: Check integrity of bolts in the panel/mainframe connection. Check for evidence of water leaks. Use silicon RTV to seal any potential leaks. Visually inspect nacelle/mainframe connection for cracks or excessive corrosion. Ensure hatch tether is connected. Maintenance Northwind 100 Wind Turbine- Maintenance 8-20 8.13 ELECTRICAL SYSTEMS 8.13.1ELECTRICAL SYSTEM MAINTENANCE GUIDELINES The electrical portions of the Northwind® 100 are designed to be highly reliable and ideally, maintenance-free. However, performing periodic checkups on the electrical systems can often identify problems that may lead to premature failure, and prompt resolution of any issues found increases the reliability and longevity of the system. Most components within electrical enclosures are serviceable; however the specific procedures for even common component replacement/repairs are not documented here. For this reason, it is imperative to communicate to Northern Power the results of all electrical maintenance checkups in case a particular specialized service operation is necessary. As the following maintenance procedures are performed, keep a list of any issues that are found, and how they were addressed (if so). Capturing pictures of any problems is also helpful in documenting and diagnosing issues and is highly recommended as a standard maintenance practice. Following any maintenance operations that involve opening any electrical enclosures, it is required to remove all tools, test gear, and other maintenance items, and verify that all parts and pieces are re-assembled or otherwise in their correct places before closing the cabinet door(s) and returning the system to service. 8.13.2INSPECT CONTROLLER To inspect the controller: Use the base service switch to shut the turbine down. Open the DX01 Main Disconnect. Lockout/Tag out the Disconnect. If opening Base Junction Box be very careful if the 480 V utility feed is still live. Climb the tower Open the cabinet doors Visually inspect all components and connections are free of corrosion, dirt and damage. Maintenance Northwind 100 Wind Turbine- Maintenance 8-21 Pay close attention to unusual discolorations, loose wires or bolted connections, evidence of moisture or water seepage, excessive dust collection, etc. Clean any dust with a dry (or slightly moist) cloth. Utilize a vacuum if available. Inspect all inlet and outlet vents for blockage, and clean or replace inlet air filters as needed. Inspect the power terminals for signs of discoloration, fraying strands, loose connections etc., and disconnect, clean, and re-terminate as needed. Tighten the generator wires connections to 21 Nm (192 in-lbs). Tighten all other large cable connections to 18 Nm (160 in-lbs). Visually inspect the dynamic brake resistor mounted to the top of the controller for evidence of heat damage. 8.13.3INSPECT TOWER CABLE To inspect tower cable: Turn off and lock out disconnect DX01 (this will remove power from the tower cables and nacelle). Turn on the rope light using the switch on the Base Junction Box and check for portions of the string that have burned out. If large sections are burned out, splice in a new section of lighting. Inspect the entire length of each tower cable for signs of chaffing or cracking. Take special care while inspecting where the cable enters the base box and where it enters the nacelle. Also inspect where it may have chaffed against the tower decks. Check that all cable clamps are tight, and that no section of the cable is making a sharp bend or kink. Check that the cables are smooth as they enter the nacelle from the tower; adjust the Kellems grip as needed. Check the tightness of the tower cable terminations, tighten to 18 nm (160 in-lbs) using a 6mm allen socket and extension. Maintenance Northwind 100 Wind Turbine- Maintenance 8-22 8.14 BRAKE PAD REPLACEMENT PROCEDURE The Brake Pads are used to slow the rotor during shutdown, and to prevent the rotor (blades) from spinning while the turbine is stopped or in Service mode. They are inspected annually, (refer to the Maintenance section) and replaced approximately every 5 years. Should they need replacing, the HMI will indicate the fault “SYS_BRAKE_A_PAD_WEAR_FAULT”, and the wind turbine will shut down. Before beginning the replacement of the brake pad, make sure you have all the necessary tools and materials on-hand. 8.14.1MATERIALS/TOOLS REQUIRED Allen wrench M4, M5, M6, M8 ½” drive socket, M22 or 7/8” ¾” drive socket, M22 or 7/8” ½” extension 3” long ¾” extension 3” long ¾” extension 16” long Torque wrench ½” 250ftlb. ¾” drive ratchet Wrench M17 Wrench M13 Wrench M10 Pliers Loctite® 243 Torque Seal Hook Tool Maintenance Northwind 100 Wind Turbine- Maintenance 8-23 8.14.2BEFORE REMOVING THE FINGER GUARD Before starting work, ensure both brakes are applied. This is accomplished by switching the control switches of both mechanical brakes to the “Full Torque” or “Half Torque” position. Only one brake should be serviced at a time. The other brake needs to be fully applied to keep the rotor stopped. If the rotor speed exceeds 10 RPM in the Service state, the turbine will fault on over-speed and will perform a fast shutdown (full-torque brake). 8.14.3REMOVING THE FINGER GUARD Remove the black plastic cover (finger guard) with an M6 allen wrench. Refer to Figure 8-14 - Removing the Finger Guard Maintenance Northwind 100 Wind Turbine- Maintenance 8-24 Installing the assembly bracket Figure 8-14 - Removing the Finger Guard Maintenance Northwind 100 Wind Turbine- Maintenance 8-25 Installing the assembly bracket Install the assembly bracket (safety clamp) on the detent clutch. Tighten the screws using an M5 allen wrench. Figure 8-15 - Installing the Safety Clamp Figure 8-16 - Safety Clamp Installed SAFETY CLAMP SAFETY CLAMP Maintenance Northwind 100 Wind Turbine- Maintenance 8-26 8.14.4REMOVING THE COVER BOLTS Remove the 2 wear adjuster safety cover bolts (if equipped) with an M13 wrench. Not all brake assemblies have this safety cover. Figure 8-17 - Removing the Wear Adjuster Safety Cover Bolts SAFETY COVER Maintenance Northwind 100 Wind Turbine- Maintenance 8-27 8.14.5REMOVING THE ADJUSTER COVER SCREWS Remove the 4 wear adjuster cover bolts with an M10 wrench, by turning the wrench counter-clockwise. Figure 8-18 - Removing the Adjuster Cover Screws Maintenance Northwind 100 Wind Turbine- Maintenance 8-28 Install 2 of the screws from the plastic cover into tapped holes near the center of the adjuster cover to facilitate removal. Figure 8-19 - Removing the Adjuster Cover Remove adjuster cover by turning the cover clockwise and pulling gently. In Figure 8-19, the wrench is being used for leverage between the two inserted screws. Maintenance Northwind 100 Wind Turbine- Maintenance 8-29 Figure 8-20 - Removing Allen Head Screws Remove the 4 allen head screws using an M5 allen wrench. Insert one screw to have something to assist in removal of the wear adjuster, if necessary. Note:Due to having Loctite on the threads, it may be necessary to remove the bolts with pliers. Maintenance Northwind 100 Wind Turbine- Maintenance 8-30 Figure 8-21 - Removing the Bolts from the Wear Adjuster Maintenance Northwind 100 Wind Turbine- Maintenance 8-31 8.14.6REMOVING THE ADJUSTER Once the bolts have been removed, pull the wear adjuster out gently. Figure 8-22 - The Wear Adjuster Release the brake using the controls on the converter panel located in the nacelle. ONLY ONE BRAKE SHOULD BE RELEASED AT ANY GIVEN TIME! Maintenance Northwind 100 Wind Turbine- Maintenance 8-32 The brake can also be released manually using a 5mm allen wrench, by inserting the wrench into the actuator. Figure 8-23 - Releasing the brake manually Unplug the brake motor power cable located on the actuator motor, to prevent accidental motor operation. Figure 8-24 - The Brake Motor Power Cable Maintenance Northwind 100 Wind Turbine- Maintenance 8-33 Insert an 8mm allen wrench into the adjuster screw and turn counter- clockwise until it can’t go any further, to reset the adjusting mechanism. This will travel approximately ¼ to ¾ of a turn. Figure 8-25 - Resetting the Adjuster Mechanism Maintenance Northwind 100 Wind Turbine- Maintenance 8-34 Checking the color scheme If the control system is not energized, connect the test jig to the terminal board. The original coloring scheme is as follows: Terminal Number Color Notes Terminal 1 Black Terminal 2 White Terminals 1 &2 are a separate cable Terminal 3 Black Terminal 4 White Terminal 5 Red Terminal 6 Green Terminal 7 Orange Terminal 8 Blue Terminal 9 White/gray Terminal 10 Red/gray Terminal 11 Green/gray Terminal 12 Orange/gray Maintenance Northwind 100 Wind Turbine- Maintenance 8-35 8.14.7REMOVING THE PAD HOLDER SPRINGS Remove the (4) pad holder springs by using the hook tool to grab spring and pull off the post. Figure 8-26 - The Pad Holder Springs Maintenance Northwind 100 Wind Turbine- Maintenance 8-36 The Pad Wear Signal Wires Unplug both pad wear signal wires. Figure 8-27 - The Pad Wear Signal Wires The top plug is connected to the floating pad. While working on the brake assembly, the floating pad will be located closest to you, while the fixed pad will be located further away. PAD WEAR SIGNAL P-CLIP Maintenance Northwind 100 Wind Turbine- Maintenance 8-37 Remove the allen screw securing the p-clip and wires to the brake housing, using a 4mm allen wrench. Figure 8-28 - The P-Clip These 2 wires may also be tie-wrapped or otherwise fastened together above the p-clip. Remove the (2) M20 bolts and the pad holder. From the factory, these bolts are often over-torqued. A ¾” drive wrench may be necessary for added leverage. Maintenance Northwind 100 Wind Turbine- Maintenance 8-38 Figure 8-29 - M20 Pad Holder Bolts Maintenance Northwind 100 Wind Turbine- Maintenance 8-39 Slide the old pad out of the top and replace it with the new one. Figure 8-30 - Removing the Old Brake Pad Maintenance Northwind 100 Wind Turbine- Maintenance 8-40 Reinstallation Reinstall the brake pad holder and the M20 bolts, using Loctite® 243, and torque to 330 Nm (243ft lb). Figure 8-31 - Brake Disc and Brake Pad Holder Brake pad Brake disk Maintenance Northwind 100 Wind Turbine- Maintenance 8-41 Replace the brake pads on fixed side following the same procedure for the floating pads. Remember the floating pad is closest to you; the fixed furthest away. Figure 8-32 - Reinstalling the New Brake Pads Reinstall the (4) springs onto the pad holders. Maintenance Northwind 100 Wind Turbine- Maintenance 8-42 Reset the centering device: Loosen the attachment screw with a 17mm wrench Remove the locking screws with a 4mm allen wrench Turn the centering device counter-clockwise until it clicks or ratchets Using Loctite® 243, reinsert and tighten the locking screw Tighten the attachment screw with a 17mm wrench until snug Figure 8-33 - The Centering Device ATTACHMENT LOCKING Maintenance Northwind 100 Wind Turbine- Maintenance 8-43 Reinsert the wear adjuster and turn counter-clockwise until the mounting screws align with the holes. Apply Loctite® 243 on the 4 screws and tighten snugly. Install the wear adjuster cover by screwing it in counter-clockwise until it rests level on the housing, and the mounting screw holes are aligned. Using Loctite® 243, install the 4 screws in the cover. Tighten until snug. Reinstall the safety cover using Loctite® 243 on the (2) bolts and tighten until snug. Plug in the pad wear connectors. Ensure the wires are routed so that they are not touching the brake disk. Reinstall the wire p-clip. Replace motor electrical plug and actuate the brakes 3-4 times. Check the gap. There should be 1 mm on the fixed side and 1.5 - 2mm on the floating side of the disk, with the brake released. There will be a larger gap on the floating side. Ensure there is an air gap on the fixed side. Figure 8-34 - Checking the Pad Gap With the brake applied, remove the safety clamp using an M5 allen wrench. Remove the temporary wiring, if used, to apply/release the brake. Maintenance Northwind 100 Wind Turbine- Maintenance 8-44 Reinstall the finger guard. Maintenance Northwind 100 Wind Turbine- Maintenance 8-45 8.15 NORTHWIND® 100 MAINTENANCE CHECKLISTS & BOLT TORQUE TABLE Complete the tasks outlined in this checklist once (1) per year. Annual Maintenance Checklist Task Initials Comments Replace main shaft bearing grease cartridges, set to 12 months Empty grease catch container Check yaw gearbox oil level, fill if necessary Grease yaw bearing (1 tube) Clean excess grease off inside of yaw bearing Grease open yaw gearing with a light coating of open gear lubricant, or yaw gearbox oil. Check and record brake pad gap Gaps: Brake A Fixed______ Floating______ Brake B Fixed______ Floating______ Check and record brake pad material thickness Thickness: Brake A Fixed______ Floating______ Brake B Fixed______ Floating______ Check brake signals (cycle brakes, Maintenance Northwind 100 Wind Turbine- Maintenance 8-46 Task Initials Comments verify no faults), check pad wear circuit Clean up (vacuum) brake dust Inspect base junction box Inspect tower cable Inspect uptower controller and electrical subsystems Verify yaw count (cable twists match SmartView) Inspect fall restraint system Replace yaw friction pads Visually inspect hub and blades Inspect lightning protection system Visually inspect main shaft Visually inspect mainframe and rearframe Inspect nacelle, fire extinguisher, ropelight, FAA light, wind sensor heaters Replace tower door air filter(s) Maintenance Northwind 100 Wind Turbine- Maintenance 8-47 Bolt Torque Check Table Connection Torque N-m (ft-lb) Min # or % of Fasteners to verify Wrench Size Accepte d (Initial) Comments Tower Bottom Section/ Foundation 715 (525) MIN 10%Site Specific Site Specific Tower Mid Section / Tower Bottom Section 505 (372) 10%30 or 32mm Tower Top Section / Tower Mid Section 505 (372) 10%30 or 32mm Yaw Bearing / Tower Top Section 252 (186) 4 24mm Mainframe / Yaw Bearing 252 (186) 4 24mm Yaw Brakes 176 (130) 6 24mm Yaw Brake Preload Screw 107 (79) 3 46mm Generator / Mainframe 176 (130) 4 24mm Hub / Mainshaft 505 (372) 8 30mm Blade 1 / Hub 505 (372) 4 30mm Blade 2 / Hub 505 (372) 4 30mm Blade 3 / Hub 505 (372) 4 30mm Yaw Drive / Mainframe 72 (53) 4 19mm Rearframe / Mainframe 176 (130) 100% 24mm Maintenance Northwind 100 Wind Turbine- Maintenance 8-48 Time Available:__________________________________________________________________ Total Energy Produced: __________________________________________________________ Notes/Comments: _______________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ Tower Cable Supports 252 (186) 100% 24mm Nacelle Panel Bolts (Fiberglass to Steel) 9 (6) 100% 10mm Converter Mounts (Vibration Isolators) 42 (31) 2 19mm Lightning Plate Fasteners 79 (58) 100% 19mm Nacelle Roof Plate Fasteners 9 (6) 20% 10mm Speed Sensor Mount Fasteners Snug 100% 10mm Generator Access Panel Fasteners Snug 100% 10mm Nacelle J-Box Fasteners Snug 100% 5mm hex Encoder Anti-Rotate Bracket Snug 100% 10mm Rearframe Brace Mounts (If Equipped) 176 (130) 100% 24mm Rearframe Brace Turnbuckles (If Equipped) Snug 2 24mm/30m m Open- end Check Jam nuts and turnbuckle Maintenance Northwind 100 Wind Turbine- Maintenance 8-49 ________________________________________________________________________________ ________________________________________________________________________________ Technician/Engineer________________________Date________________________________ Maintenance Northwind 100 Wind Turbine- Maintenance 8-50 Extended Service Items Complete the tasks outlined in this checklist once (1) per every 5 years. Task Initials Comments Five (5) year Service Interval Inspect Blades, clean and/or repair if necessary Replace Mechanical Brake Pads if not replaced already Drain yaw drive gear oil. Refill with new oil (Mobil SHC 629 or 630) Ten (10) year Service Interval Complete all five (5) year maintenance items Change Power Converter DC Bus Capacitors Time Available:__________________________________________________________________ Total Energy Produced: __________________________________________________________ Notes/Comments: _______________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ Technician/Engineer________________________Date________________________________ Maintenance Northwind 100 Wind Turbine- Maintenance 8-51 Appendix A- Troubleshooting Northwind 100 Wind Turbine- Troubleshooting 9-1 9 TROUBLESHOOTING The following table provides alarm list and a brief description of the problem. Alarm Definitions Alarm Name Type Description CNV_ISR_OVERRUN Fault Processor too busy CNV_ISR2_OVERRUN Fault Processor too busy CNV_ESTOP_FAULT External Safety circuit opened CNV_OVERSPEED_RELAY_FAULT Fault Overspeed relay has tripped CNV_SEL_RELAY_FAULT SEL Relay (Option) has tripped CNV_MCMIB_NOT_PRESENT Fault MCMIB not present CNV_MC_NOT_CLOSED Fault Main contactor failed to close CNV_DC_V_BUS_HI Fault DC bus voltage high CNV_DC_V_BUS_LO Fault DC bus voltage low CNV_DC_V_IMB_HI Fault DC bus voltage imbalance high CNV_DC_V_IMB_LO Fault DC bus voltage imbalance low CNV_AVG_DC_V_BUS_HI Fault DC bus average voltage high CNV_AVG_DC_V_BUS_LO Fault DC bus average voltage low CNV_AVG_DC_V_IMB_HI Fault DC bus average voltage imbalance high CNV_AVG_DC_V_IMB_LO Fault DC bus average voltage imbalance low CNV_AVG_DC_PRECHARGE_V_LO Fault DC bus average voltage low during pre-charge CNV_AVG_P_LOSS_HI Fault Power imbalance detected ALARM_CNV_AVG_DBL_P_HI Excessive power into the brake resistor CNV_ENCODER_FAULT Fault Encoder is not behaving correctly CNV_ENCODER_HOME_PULSE_MISSING Fault Generator encoder home pulse signal failed CNV_TEMP_L12_HI Fault L12 Inductor temperature high CNV_TEMP_CAB_HI Fault Cabinet temperature high CNV_TEMP_CAB_LO Environmental Cabinet temperature low CNV_TEMP_BUS_CAP_HI Fault DC bus capacitor temperature high CNV_TEMP_AMB_HI Environmental Ambient temperature high CNV_TEMP_AMB_LO Environmental Ambient temperature low Appendix A- Troubleshooting Northwind 100 Wind Turbine- Troubleshooting 9-2 Alarm Name Type Description CNV_TEMP_GEN1_HI Fault Generator temperature A high CNV_TEMP_GEN1_LO Environmental Generator temperature A low CNV_TEMP_GEN2_HI Fault Generator temperature B high CNV_TEMP_GEN2_LO Environmental Generator temperature B low CNV_TEMP_GEN_DELTA_HI Fault Generator temperature delta high CNV_TEMP_MIB_HI Fault MCMIB temperature high CNV_ACCELERATION_DW_HI Fault Excessive acceleration in the fore-aft direction CNV_ACCELERATION_XW_HI Fault Excessive acceleration in the side-side direction CNV_VIBRATION_DW_HI Fault Excessive vibration in the fore-aft direction CNV_VIBRATION_XW_HI Fault Excessive vibration in the side-side direction CNV_ACCELEROMETER_FAIL Fault Accelerometer sensor fault ALARM_CNV_DBL_DRIVER_ERROR, Error in the DC Bus limiter driver circuit or IGBT ALARM_CNV_DBL_TEST_FAIL, DC Bus Limiter resistance check failed ALARM_CNV_AVG_P_BASELINE_HI Power losses within the converter are exceeding expected limits ALARM_CNV_EXTERNAL_24VAC_FAIL The controller 24VAC power supply is not functioning correctly ALARM_CNV_EXTERNAL_24VDC_FAIL A failure has occurred within one of the 24 VDC circuits, specific versions of this fault exist to help diagnosing fuse failure ALARM_CNV_THERM_L12_FAIL The thermistor mounted on the L12 inductor has failed ALARM_CNV_THERM_CAB_FAIL The thermistor mounted in the converter cabinet has failed ALARM_CNV_THERM_BUS_CAP_FAIL The thermistor mounted on a DC bus capacitor has failed ALARM_CNV_THERM_AMB_FAIL The thermistor mounted on the MET mast has failed ALARM_CNV_THERM_GEN1_FAIL A thermistor mounted inside the generator has failed ALARM_CNV_THERM_GEN2_FAIL A thermistor mounted inside the generator has failed ALARM_CNV_THERM_MIB_FAIL The thermistor mounted on the MCMIB board has failed Appendix A- Troubleshooting Northwind 100 Wind Turbine- Troubleshooting 9-3 Alarm Name Type Description CNV_INT_WATCHDOG_ERR Fault Processor to processor communications on the control board have failed CNV_INT_FPGA_ACCESS_ERR Processor access to the FPGA device on the control board has failed CNV_INT_MCMIB_ACCESS_ERR Processor access to the MCMIB board has failed SYS_INT_WATCHDOG_ERR Fault Processor to processor communications on the control board have failed SYS_INT_FPGA_ACCESS_ERR Fault Coldfire FPGA access error SYS_DISPATCH_WATCHDOG_ERR External Dispatch comm. watchdog fault SYS_HMI_DISABLE External Turbine has been disabled at the HMI (Smartview) SYS_DISPATCH_DISABLE Turbine has been disabled by a dispatch controller SYS_WIND_HI Environment al Wind speed too high to run turbine SYS_YAW_SNSR_CHATTER_FAULT The yaw system is moving around slightly SYS_YAWVANE_SNSR_FAULT Fault Yaw vane sensor failed SYS_ANEMOMETER_SNSR_FAULT Fault Anemometer Sensor Fault SYS_TSTATE_RTR_SPD_SNSR_FAULT Fault Indicates difference between PLL.RPM and tachometer speed too great SYS_TSTATE_RTR_MOTION_WRONG_TIME Fault Unexpected rotor motion detected , erroneous speed indication or brake pad failure SYS_TSTATE_TACH_OVERSPEED Fault Tachometer speed too high SYS_TSTATE_ANEM_PWR_MISMATCH Fault Turbine power too high for measured wind speed SYS_TSTATE_MOTOR_TIME_FAULT Fault Turbine spent too much time motoring SYS_YAW_MOTOR_OVERLOAD Fault Yaw motor overload SYS_YSTATE_YAW_MOTION_NOT_DETECTED Fault Yaw commanded but not detected SYS_YSTATE_YAW_VANE_TIMEOUT Fault Yaw vane did not change position when expected (during yaw motion) SYS_YSTATE_UNWANTED_YAW_MOTION Warning Yaw Action Detected with No Command SYS_YSTATE_YAW_UNWIND_TIMEOUT Warning Yaw unwind too long SYS_YSTATE_YAWING_FAST Warning Yawing faster than expected SYS_YSTATE_YAWING_SLOW Warning Yawing slower than expected Appendix A- Troubleshooting Northwind 100 Wind Turbine- Troubleshooting 9-4 Alarm Name Type Description SYS_YSTATE_YAW_WRONG_DIRECTION Fault Yawing wrong direction" SYS_YSTATE_YAW_MISSED_COUNT Warning Yaw missed count SYS_POWER_CONVERTER_FAULT, Fault General indicator that a fault occurred within the power converter subsystem SYS_POWER_CONVERTER_EXTERNAL_FAULT Fault General indicator that an External influence caused the power converter system to shutdown SYS_POWER_CONVERTER_ENVIRONMENTAL_ FAULT Fault General indicator that an Environmental influence caused the power converter system to shutdown SYS_BRAKE_A_NOT_APPLY_FAULT Fault Mechanical brake failed to apply or brake is released when it is supposed to be applied SYS_BRAKE_A_NOT_RELEASE_FAULT Fault Mechanical brake failed to release or brake is applied when it is supposed to be released SYS_BRAKE_B_NOT_APPLY_FAULT Fault Mechanical brake failed to apply or brake is released when it is supposed to be applied SYS_BRAKE_B_NOT_RELEASE_FAULT Fault Mechanical brake failed to release or brake is applied when it is supposed to be released SYS_BRAKE_A_PAD_WEAR_FAULT Fault Brake pads on brake A need replacement SYS_BRAKE_B_PAD_WEAR_FAULT Fault Brake pads on brake B need replacement SYS_TSTATE_BRK_TEST_FAILED Fault The brakes are not providing enough torque SYS_CNV_INVALID_STATE Fault The power converter was commanded to change states and it did not respond INV_IGBT_BRG1_ERROR Fault Error bits coming from SKiiP (inverter IGBT assy) INV_IGBT_BRG2_ERROR Fault Error bits coming from SKiiP (inverter IGBT assy) INV_IGBT_BRG3_ERROR Fault Error bits coming from SKiiP (inverter IGBT assy) INV_IGBT_TEMP_ERROR Fault Error bits coming from SKiiP (inverter IGBT assy) INV_PLL_PHASE_SEQ_ERROR Fault Phase rotation is incorrect ALARM_INV_PLL_NOT_LOCKED Warning A grid condition is preventing the inverter from beginning the synchronization process INV_AC_RMS_V1_HI Fault Inverter (grid) RMS voltage high (level 1) INV_AC_RMS_V2_HI Fault Inverter (grid) RMS voltage high (level 2) INV_AC_RMS_V3_HI Fault Inverter (grid) RMS voltage high (level 3) INV_AC_RMS_V1_LO Fault Inverter (grid) RMS voltage low (level 1) INV_AC_RMS_V2_LO Fault Inverter (grid) RMS voltage low (level 2) Appendix A- Troubleshooting Northwind 100 Wind Turbine- Troubleshooting 9-5 Alarm Name Type Description INV_AC_RMS_V3_LO Fault Inverter (grid) RMS voltage low (level 3) INV_AC_AVG_FREQ1_HI Fault Inverter (grid) frequency is high (level 1) INV_AC_AVG_FREQ2_HI Fault Inverter (grid) frequency is high (level 2) INV_AC_AVG_FREQ3_HI Fault Inverter (grid) frequency is high (level 3) INV_AC_AVG_FREQ1_LO Fault Inverter (grid) frequency is low (level 1) INV_AC_AVG_FREQ2_LO Fault Inverter (grid) frequency is low (level 2) INV_AC_AVG_FREQ3_LO Fault Inverter (grid) frequency is low (level 3) INV_AC_I_A_HI Fault Inverter instantaneous overcurrent (Phase A) INV_AC_I_B_HI Fault Inverter instantaneous overcurrent (Phase B) INV_AC_I_C_HI Fault Inverter instantaneous overcurrent (Phase C) INV_AC_RMS_I_HI Fault Inverter RMS (any phase) current high INV_AC_RMS_I_IMB_HI Fault Inverter phase currents imbalanced INV_AC_RMS_I_TOTAL_HI Fault Inverter Total RMS current high (Ground fault) INV_AC_AVG_V_HI Fault Inverter grid DC voltage content high INV_AC_AVG_V_LO Fault Inverter grid DC voltage content low (negative) INV_AC_AVG_I_HI Fault Inverter output DC content high INV_AC_AVG_I_LO Fault Inverter output DC content low (negative) INV_TEMP_IGBT_HI Fault Inverter semiconductor (IGBT) temperatures high REC_IGBT_BRG1_ERROR Fault Error bits coming from SKiiP (rectifier IGBT assy) REC_IGBT_BRG2_ERROR Fault Error bits coming from SKiiP (rectifier IGBT assy) REC_IGBT_BRG3_ERROR Fault Error bits coming from SKiiP (rectifier IGBT assy) REC_IGBT_TEMP_ERROR Fault Error bits coming from SKiiP (rectifier IGBT assy) REC_PLL_PHASE_SEQ_ERROR Fault Generator phase rotation is incorrect REC_PLL_NOT_LOCKED Warning Rectifier is not synchronizing with the generator correctly REC_AC_AVG_RPM_HI Fault Turbine is spinning too quickly Appendix A- Troubleshooting Northwind 100 Wind Turbine- Troubleshooting 9-6 Alarm Name Type Description REC_AC_AVG_RPM_LO Fault Turbine is spinning the wrong direction REC_AC_I_A_HI Fault Rectifier instantaneous overcurrent (Phase A) REC_AC_I_B_HI Fault Rectifier instantaneous overcurrent (Phase B) REC_AC_I_C_HI Fault Rectifier instantaneous overcurrent (Phase C) REC_AC_RMS_I_A_HI Fault Rectifier RMS overcurrent (Phase A) REC_AC_RMS_I_B_HI Fault Rectifier RMS overcurrent (Phase B) REC_AC_RMS_I_C_HI Fault Rectifier RMS overcurrent (Phase C) REC_AC_RMS_I_TOTAL_HI Fault Rectifier Total RMS current high (Ground fault) REC_AC_AVG_V_HI Fault Generator DC voltage content high REC_AC_AVG_V_LO Fault Generator DC voltage content low (negative) REC_AC_AVG_I_HI Fault Rectifier output DC content high REC_AC_AVG_I_LO Fault Rectifier output DC content low (negative) REC_TEMP_IGBT_HI Fault Rectifier semiconductor (IGBT) temperatures high Appendix B- Drawings and Diagrams Northwind 100 Wind Turbine- Drawings and Diagrams 10-1 10 DRAWINGS AND DIAGRAMS The following drawings and diagrams are included in this manual. 10.1 ELECTRICAL DRAWINGS AND DIAGRAMS Electrical Drawings and Diagrams Drawing Number Description J00206 Single Line Diagram J00295 Protective Relay Overview Schematic 10.2 MECHANICAL DRAWINGS AND DIAGRAMS Mechanical Drawings and Diagrams Drawing Number Description 1001000 Nacelle Assembly 1001176 Rotor Assembly 1000169 Yaw Brake Assembly 1001313 Tower Assembly, 37m 1000148 FAA Light Assembly 10.3 GENERAL DRAWINGS AND DIAGRAMS General Drawings and Diagrams Drawing Number Description A00281 General Specification A00298 Application Requirements Document Appendix B- Drawings and Diagrams Northwind 100 Wind Turbine- Drawings and Diagrams 10-2 Drawing Number Description A00293 Protective Relay Specification Appendix B- Drawings and Diagrams Northwind 100 Wind Turbine- Drawings and Diagrams 10-3 10.4 VENDOR DOCUMENTATION The following vendor documentation is included in this manual. Vendor Documentation Component Manufacturer Documentation Brakes Hanning and Kahl 2008-09-18 H&K Operating Manual HEPW60S Rev.00.pdf Sample Northern Power Wind Technician Training Program Outline Day 1 8:30 – 9:00 Introductions and Safety Briefing 9:00 – 10:00 Factory Overview & Tour 10:00 -10:15 Break 10:15 – 11:00 Turbine Overview & Wind basics 11:00 – 12:00 Overview of Installation Components and Flow 12:00 – 1:00 Lunch 1:00 – 2:15 Review o The tower & base section –shop tour o Un-nesting procedure, lifting, hoisting o Blade Pitching 2:15 - 2:30 Break 2:30 – 4:00 Shop Tour (con’t) – Blade Pitching 4:00 -4:30 Safety Overview o Harness/Climbing Day 2 7:00 – Meet at Northern Power – Spend Day at Installed turbine location Day 3 8:30 – 9:00 Recap from Site Visit 9:00 – 10:00 Turbine Construction/ Assembly o Best Practices - Rotor and Nacelle o Keeping Track o Electrical Work 10:00 – 10:15 Break 10:15 – 12:00 Turbine Operation / Maintenance - Overview 12:00 – 1:00 Lunch 1:00 – 4:00 Floor Time o Turbine Maintenance