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HomeMy WebLinkAboutASRC-BRW-RSA Barrow Public Works 2012-EE Richard S. Armstrong, PE, LLC Comprehensive Energy Audit Barrow Public Works Project # The North Slope Borough Department of Public Works Richard S. Armstrong, PE, LLC 2321 Merrill Field Drive, C Barrow Public Works Office Barrow Public Works Office Comprehensive Energy Audit 3 REPORT DISCLAIMERS The information contained in this report, including any attachments, is intended solely for use by the building owner and the AHFC. No others are authorized to disclose, copy, distribute or retain this report, in whole or part, without written authorization from Richard S. Armstrong, PE, LLC, 2321 Merrill Field Drive, C-6, Anchorage, Ak 99501. Additionally, this report contains recommendations that, in the opinion of the auditor, will cause the owner to realize energy savings over time. All recommendations must be designed by a registered engineer, licensed in the State of Alaska, in the appropriate discipline. Lighting recommendations should all be first reviewed by running a lighting analysis to assure that the recommended lighting upgrades will comply with State of Alaska Statue as well as IES recommendations. Payback periods may well vary from those forecast due to the uncertainty of the final installed design, configuration, equipment selected, and installation costs of recommended Energy Efficiency Measures (EEMs), or the operating schedules and maintenance provided by the owner. Furthermore, EEMs are typically interactive, so implementation of one EEM may impact the cost savings from another EEM. Neither the auditor, Richard S. Armstrong, PE, LLC, AHFC, or others involved in preparation of this report will accept liability for financial loss due to EEMs that fail to meet the forecasted payback periods. This audit meets the criteria of an Investment Grade Audit (IGA) per the Association of Energy Engineers definition, and is valid for one year. The life of the IGA may be extended on a case-by-case basis, at the discretion of the AHFC. IGSs are the property of the State, and may be incorporated into AkWarm- C, the Alaska Energy Data Inventory (ARIS), or other state and/or public information system Barrow Public Works Office Comprehensive Energy Audit 4 Investment Grade Energy Audit Barrow Public Works Office 1. Executive Summary: The Barrow Public Works Office Was Originally constructed in 1976 as a 29-unit apartment building. In 2005, the building underwent a complete renovation and has been used 100% as an office for the NSB Public Works Department. The facility contains 52 offices, four restrooms, three storage rooms, two conference rooms, two break rooms, a mechanical bay, a reception area, and a lobby. The building is in good condition. The 2010 and 2011 annual utility energy consumption reported by BUECI and collected as benchmark data by WHPacific, Inc. is displayed in Table 1 below: Table 1 2010 2010 2011 2011 Utility Consumption Cost/Year Consumption Cost/Year Electricity-kWh 244,080 $25,862 235,280 $26,988 Natural Gas-CCF 26,886 $8,245 31,251 $9,576 Total Energy Costs $34,107 $36,564 A benchmark measure of energy use relative to other similar function buildings in the area is the Energy Use Index (EUI), which takes the total annual energy used by the facility divided by the square footage area of the building, for a value expressed in terms of kBTU/SF. This number can then be compared to other buildings to see if it is about average, higher or lower than similar buildings in the area. Likewise, the Energy Cost Index (ECI) is the cost of all energy used by the building expressed in $/SF of building area. The comparative values for the subject building are listed in Table 2 below: Table 2 Public Works Barrow Avg NSB Admin Bldg Energy Use Index (EUI) kBTU/SF 154 224 238 Energy Cost Index (ECI) $/SF $1.51 $1.83 $2.42 Various Energy Efficiency Measures (EEMs) have been analyzed for this building to determine if they would be applicable for energy savings with reasonably good payback periods. Those EEMs that Barrow Public Works Office Comprehensive Energy Audit 5 have a payback period of less than 8 years, or those that are recommended for code compliance, life cycle replacement, or other reasons are also included. Also, where a lighting upgrade is recommended from T-12 lamps with magnetic ballasts to T-8 lamps with electronic ballasts, then the entire facility should be relamped and reballasted to maintain a standard lighting parts inventory, regardless of the payback. For example, a storage room that is infrequently used may not show a very good payback for a lighting upgrade, but consistency dictates a total upgrade. Specific EEMs recommended for this facility are detailed in the attached AkWarm Energy Audit Report along with specific payback times, as well as estimated installation costs and estimated energy savings. The higher priority items are summarized below: a. Exterior Lighting Upgrades: The exterior high pressure sodium lights operate during periods of darkness, which is about half of a year. It is estimated that the use of LED exterior lights can reduce the power consumption by 60%. b. Air Handler Unit Cycling: The AHU-1 currently operates 24/7 because it is in manual rather than auto mode. AHU-1 is meant to ventilate the south wing of the building, which is unoccupied during non-business hours. The purpose of this EEM is to only start AHU-1 when the south wing is occupied. c. Air Handler Unit Summer Pre-Filters: AHU-1 and AHU-2 have pre-filters for filtration of summer dust. These should be removed in the winter to prevent clogging from snow. This has been seen to lower the building CO2 levels by over 10%, and decreases the load on the AHUs. d. Glycol Circulation Pumps: The hydronic heating system is designed to have two sets of glycol loops run by two circulation pumps, CP-1 and CP-2, running at the pumps’ preset speed 2. A third pump, CP-3 is plumbed-in as a backup to either CP-1 or CP-2 and should be run only when another pump fails. All three pumps were found running 24/7, with CP-3 running on speed 3. Operation of the third pump is causing the control valves to bypass, thus overheating the building and wasting energy (from both the pump and heat loss). Barrow Public Works Office Comprehensive Energy Audit 6 Additionally, CP-2 was found to be set on speed 3. This is also exceeding the designed flow and wasting money and energy. CP-3 should be switched to “auto” rather than “hand”, and CP-2 should be switched to speed 2 rather than speed 3. These EEMs require minimal time and effort and give a combined instant payback of $1,088 per year. e. Headbolt Heater Controls: Leaving the headbolt heaters energized 24/7 is unnecessary for typical winter temperatures in Barrow. The building already has a timer system installed, but it has had the dogs removed. This timer should be returned to auto and tested. Returning the timer to service and cycling the headbolt heaters every 20- minutes (20-minutes on, 20-minutes off) will still maintain vehicle components at adequate temperatures and may save around $2,500 per year. In addition to EEMs, various Energy Conservation Measures (ECMs) are recommended since they are policies or procedures that are followed by management and employees that require no capital outlay. Examples of recommended ECMs for this facility include: • Turn off lights when leaving a room that is not controlled by an occupancy sensor that automatically turns off lights. • Turn off computers, monitors, printers, faxes, coffee makers, etc when leaving the office for the day. • Keep overhead doors closed except when they are required to be open for movement of vehicles. The 10 priority recommendations in the detailed report estimate to save $ 10,940/year, with an installed cost of $ 14,354. This does not include design or CA services, but overall it does indicate a cost effective energy savings program. 2. Audit and Analysis Background: a. Program Description: This audit included services to identify, develop, and evaluate energy efficiency measures at the subject building. The scope of this project included evaluating the building shell, lighting, other electrical systems, and heating, ventilating, and air conditioning (HVAC) equipment. Barrow Public Works Office Comprehensive Energy Audit 7 Measures were selected such that an overall simple payback period of 8 years or less could be achieved. b. Audit Description and Methodology: Preliminary audit information was gathered in preparation for the site survey, including benchmark utility consumption data, floor and lighting plans, and equipment schedules where available. A site visit is then performed to inventory and evaluate the actual building condition, including: i. Building envelope (roof, windows, etc) ii. Heating, ventilating, and air conditioning iii. Lighting systems and controls iv. Building specific equipment v. Plumbing systems c. Method of Analysis: The information gathered prior to the site visit and at the site visit is entered into AkWarm-C, an energy modeling developed for Alaska Housing Finance Corporation (AHFC) specifically to identify forecasted energy consumption which can be compared to actual energy consumption. AkWarm-C also has some pre-programmed EEM retrofit options that can be analyzed with energy savings forecasted based on occupancy schedules, utility rates, building construction type, building function, existing conditions, and climatic data that is already uploaded to the program based on the zip code of the building. When new equipment is proposed, energy consumption is calculated based on manufacturer’s cataloged information. Cost savings are calculated based on the historical energy costs for the building. Installation costs include labor and equipment to estimate the full up-front investment required to implement a change, but design and construction management costs are excluded. Costs are derived from Means Cost Data, industry publications, experience of the auditor, local contractors, and equipment suppliers. Applicable maintenance savings were calculated and added to the energy savings for each EEM. Barrow Public Works Office Comprehensive Energy Audit 8 The cost and savings are applied and a simple payback and simple return on investment (ROI) is calculated. The simple payback is based on the number of years that it takes for the savings to pay back the net installation cost (Net Installation divided by Net Savings.) A simple life-time calculation is shown for each EEM. The life- time for each EEM is estimated based on the typical life of the equipment being replaced or altered. The energy savings is extrapolated throughout the life-time of the EEM. The total energy savings is calculated as the total life-time multiplied by the yearly savings. d. Limitations of the Study: All results are dependent on the quality of input data provided, and can only act as an approximation. In some instances, several methods may achieve the identified savings. This report is not intended as a final design document. A design professional, licensed to practice in Alaska and in the appropriate discipline, who is following the recommendations, shall accept full responsibility and liability for the results. Budgetary estimates for engineering and design of these projects in not included in the cost estimate for each measure, but these costs generally run around 15% of the cost of the work. 3. Acknowledgements: We wish to acknowledge the help of numerous individuals who have contributed information that was used to prepare this report, including: a. Alaska Housing Finance Corporation (Grantor): AHFC provided the grant funds, contracting agreements, guidelines, and technical direction for providing the audits. AHFC reviewed and approved the final short list of buildings to be audited based on the recommendation of the Technical Service Provider (TSP). b. North Slope Borough (Owner): The NSB provided building sizing information, two years energy billing data, building schedules and functions, as well as building age. Barrow Public Works Office Comprehensive Energy Audit 9 c. Nortech Engineering (Benchmark TSP): Nortech Engineering compiled the data received from the NSB and entered that data into the statewide building database, called the Alaska Retrofit Information System (ARIS). d. Richard S. Armstrong, PE, LLC (Audit TSP): This is the TSP who was awarded the projects in the Arctic Slope Regional Corporation, Bering Straits area, and the Nana area. The firm gathered all relevant benchmark information provided to them by Nortech, cataloged which buildings would have the greatest potential payback, and prioritized buildings to be audited based on numerous factors, including the Energy Use Index (EUI), the Energy Cost Index (ECI), the age of the building, the size of the building, the location of the building, the function of the building, and the availability of plans for the building. They also trained their selected sub-contracted auditors, assigned auditors to the selected buildings, and performed quality control reviews of the resulting audits. They prepared a listing of potential EEMs that each auditor must consider, as well as the potential EEMs that the individual auditor may notice in the course of his audit. Richard S. Armstrong, PE, LLC also performed some of the audits to assure current knowledge of existing conditions. e. WHPacific, Inc (Audit Preparer): This firm specializes in mechanical, electrical, and civil design, and has one mechanical EIT who is a Certified Energy Auditor in Training. This CEIT has received additional training from Richard S. Armstrong, PE, LLC to acquire further specific information regarding audit requirements and potential EEM applications. WHPacific prepared this audit and submitted it for review by Richard S. Armstrong, PE, LLC. 4. Building Description and Function: The subject building is called the Barrow Public Works Building. It was originally constructed in 1976 as an apartment complex and had a complete renovation in 2005 to become an office for the North Slope Borough Department of Public Works. The total size of the building is 22704 ft2. The building has two stories. Barrow Public Works Office Comprehensive Energy Audit 10 a. Heating System: The building heating system consists of two Weil-Mclain 1080 cast iron boilers, fired sequentially. Hot glycol is distributed to baseboard heaters, a unit heater, and the air handler coils through copper pipe. b. Ventilation System: Two make up air units supply air to the building. These are labeled AHU-1 and AHU-2 and are located in the mechanical room. AHU-1 supplies air to the south wing at a rate of 1960 CFM. AHU-2 supplies air to the north wing at a rate of 1510 CFM. The south wing is exhausted with a 2000 CFM exhaust fan, and a 1600 CFM exhaust fan pulls air from the north wing. The two first floor restrooms are exhausted with individual 330 CFM exhaust fans. The two second floor restrooms are exhausted with a single 660 CFM exhaust fan. A 300 CFM fan exhausts the communication room. c. Plumbing System: The restrooms contain 16 toilets, 4 urinals, and 12 sinks for hand washing. The break rooms contain 2 sinks for dishes and coffee, the conference rooms contain 2 sinks, and there are 4 water fountains outside the restrooms. d. Domestic Hot Water: Hot water is generated in an Amtrol HWG, located in the mechanical room, using hot glycol from the boilers. e. Lighting: Office lighting throughout the building is composed of T-8 fluorescent fixtures with electric ballasts. The hallways are lit by wall-mounted CFLs. Exterior lighting utilizes 250, 150, and 100 watt high pressure sodium (HPS) wall packs, pole- mounted flood lights, and canopy lights. 5. Historic Energy Consumption: Energy consumption is modeled within the AkWarm-C program. The program only analyzes 12 months of data, so where 24 months of data are available, the data is averaged to provide more accuracy. The energy consumption data is presented and graphed in the attached AkWarm-C program results. Energy consumption was analyzed using two factors: the Energy Cost Index (ECI) and the Energy Use Index (ECU). Barrow Public Works Office Comprehensive Energy Audit 11 The energy cost index takes the average cost of gas and electrical energy over the surveyed period of time (typically 2 years) and averages the cost, divided by the square footage of the building. The ECI for this building is $ 1.51/SF, and the average ECI for all buildings in Barrow that were surveyed is $ 1.83/SF. The NSB Administration building, an older office building in Barrow has an ECI of $ 2.42/SF The energy use index (ECU) is the total average electrical and heating energy consumption per year expressed in thousands of BTUs/SF. The average ECU for all buildings in Barrow that were surveyed is 224 kbtu/sf, and the EUI for this building is 154 kbtu/sf, compared to 238 kbtu/sf for the NSB administration building. 6. Energy Efficiency Measures considered or recommended: The building was examined for application of a multitude of potential EEMs that are discussed below. Those EEMs that appear to have an application for the subject building are further analyzed for estimated payback periods, either within the AkWarm-C program or separately within this report. The accuracy of the cost estimates and paybacks varies significantly due to a multitude of conditions, but is estimated to be approximately +/- 25%. Assumptions made regarding energy costs and the life of the EEM, noting that post-construction measurement and verification are based on energy savings, not energy cost savings. Many of the selected EEMs are analyzed within the AkWarm-C program using the schedules and estimated costs input into the model. Some of the other EEMs are not modeled within AkWarm-C, and are individually discussed within this report. 7. Interactive Effects of Projects: The AkWarm-C program calculates savings assuming that all recommended EEM are implemented. If some EEMs are not implemented, savings for the remaining EEMs will be affected, in some cases positively, and in others, negatively. For example, if the pump motor’s speed is not reduced, then the savings for putting the pump on “auto” will be increased. In general, all projects were evaluated sequentially so that energy savings associated with one EEM would not be attributed to another Barrow Public Works Office Comprehensive Energy Audit 12 EEM as well. For example, the unoccupied thermostat setback EEM was analyzed using the fan and heating load profile that will be achieved after switching AHU-1 to “auto”. By modeling the recommended projects sequentially, the analysis accounts for interactive effects between the EEMs and does not “double count” savings. Interior lighting, plug loads, facility equipment, and occupants generate heat within the building. When the building is in cooling mode, these contribute to the overall cooling demands of the building; therefore lighting efficiency improvements will reduce cooling requirements on air conditioned buildings. Conversely, lighting efficiency improvements are anticipated to increase heating requirements slightly. Heating penalties are included in the lighting project analysis that is performed by AkWarm-C. 8. Loan Program: The Alaska Housing Finance Corporation (AHFC) Alaska Energy Efficiency Revolving Loan Fund (AEERLF) is a State of Alaska program enacted by the Alaska Sustainable Energy Act (senate Bill 220, A.S. 18.56.855, “Energy Efficiency Revolving Loan Fund). The AEERLF will provide loans for energy efficiency retrofits to public facilities via the Retrofit Energy Assessment for Loan System (REAL). As defined in 15 AAC 155.605, the program may finance energy efficiency improvements to buildings owned by: a. Regional educational attendance areas; b. Municipal governments, including political subdivisions of municipal governments; c. The University of Alaska; d. Political subdivisions of the State of Alaska, or e. The State of Alaska Native corporations, tribal entities, and subsidiaries of the federal government are not eligible for loans under this program. Appendix A: Photos Reception area Mechanical room; boilers and circulation pump #1 shown Appendix A: Photos Mechanical room; equipment control panels, circulation pumps, and hot water generator shown Mechanical room mezzanine; Make-up air units shown Appendix A: Photos Mechanical room mezzanine; AHU-1 shown Mechanical room mezzanine; snow-clogged pre-filter shown Appendix A: Photos Snow infiltration in AHU-1 intake duct Mechanical room; headbolt heater timer Appenendix B Energy Audit – Energy Analysis and Cost Comparison AkWarm Commercial Audit Software NSB Public Works Building Page 1 ENERGY AUDIT REPORT – PROJECT SUMMARY – Created 1/10/2012 6:24 AM General Project Information PROJECT INFORMATION AUDITOR INFORMATION Building: NSB Public Works Building Auditor Company: Richard S. Armstrong, PE, LLC Address: 1689 Okpik Auditor Name: Richard S. Armstrong, David Robbins City: Barrow Auditor Address: 2321 Merrill Field Drive C-6 Anchorage, Ak 99501 Client Name: Charlie Sakeagak Client Address: PO Box 69 Barrow, AK 99723 Auditor Phone: (907) 229-0331 Auditor FAX: Client Phone: (907) 852-0489 Auditor Comment: Client FAX: Design Data Building Area: 22,704 square feet Design Heating Load: Design Loss at Space: 1,164,683 Btu/hour with Distribution Losses: 1,164,683 Btu/hour Plant Input Rating assuming 82.0% Plant Efficiency and 25% Safety Margin: 1,775,432 Btu/hour Note: Additional Capacity should be added for DHW load, if served. Typical Occupancy: 76 people Design Indoor Temperature: 68 deg F (building average) Actual City: Barrow Design Outdoor Temperature: -41 deg F Weather/Fuel City: Barrow Heating Degree Days: 20,370 deg F-days Utility Information Electric Utility: Barrow Utilities & Electric-elec - Commercial - Lg Natural Gas Provider: Barrow Utilities & Electric-gas - Commercial - Lg Average Annual Cost/kWh: $0.112/kWh Average Annual Cost/ccf: $0.307/ccf Annual Energy Cost Estimate Description Space Heating Space Cooling Water Heating Lighting Refrige ration Other Electric al Cooking Clothes Drying Ventilatio n Fans Service Fees Total Cost Existing Building $8,703 $0 $69 $7,896 $412 $14,30 2 $0 $0 $1,385 $1,222 $33,989 With Proposed Retrofits $2,815 $0 $62 $7,548 $412 $10,59 0 $0 $0 $398 $1,222 $23,048 SAVINGS $5,889 $0 $6 $348 $0 $3,711 $0 $0 $987 $0 $10,941 Appenendix B Energy Audit – Energy Analysis and Cost Comparison AkWarm Commercial Audit Software NSB Public Works Building Page 2 $0 $5,000 $10,000 $15,000 $20,000 $25,000 $30,000 $35,000 Existing Retrofit Service Fees Ventilation and Fans Space Heating Refrigeration Other Electrical Lighting Domestic Hot Water Annual Energy Costs by End Use $0 $5,000 $10,000 $15,000 $20,000 $25,000 $30,000 $35,000 Existing Retrofit Natural Gas Electricity Annual Energy Costs by Fuel Appenendix B Energy Audit – Energy Analysis and Cost Comparison AkWarm Commercial Audit Software NSB Public Works Building Page 3 PRIORITY LIST – RECOMMENDED ENERGY EFFICIENCY MEASURES Rank Feature Recommendation Annual Energy Savings Installed Cost SIR Payback (Years) 1 Ventilation change from "HAND" to "AUTO" $6,571 $1 83179.41 0 2 Other Electrical: Glycol pump speed 2 Remove Manual Switching and Add new Other Controls $841 $1 5360.77 0 3 Other Electrical: Glycol pump speed 3 Replace with pump $252 $1 1605.41 0 4 Other Electrical: Headbolt Heaters Add new Clock Timer or Other Scheduling Control $2,486 $20 1526.17 0 5 Setback Thermostat: First Floor Implement a Heating Temperature Unoccupied Setback to 60.0 deg F for the First Floor space. $224 $200 14.26 0.9 6 Setback Thermostat: Second Floor Implement a Heating Temperature Unoccupied Setback to 60.0 deg F for the Second Floor space. $218 $200 13.86 0.9 7 Lighting: Type H1 exterior Replace with 2 LED 115W Module StdElectronic $77 $2,695 0.35 35 8 Lighting: Type G exterior Replace with 5 LED 115W Module StdElectronic $179 $6,736 0.33 37.5 9 Lighting: Type K exterior Replace with LED 72W Module StdElectronic $24 $900 0.32 38.1 10 Lighting: Type H exterior Replace with 4 LED 48W Module StdElectronic $68 $3,600 0.23 53.3 TOTAL $10,941 $14,354 9.1 1.3 ENERGY AUDIT REPORT – ENERGY EFFICIENT RECOMMENDATIONS 1. Building Envelope Insulation Rank Location Existing Type/R-Value Recommendation Type/R- Value Installed Cost Annual Energy Savings Exterior Doors – Replacement Rank Location Size/Type/Condition Recommendation Installed Cost Annual Energy Savings Windows and Glass Doors – Replacement Appenendix B Energy Audit – Energy Analysis and Cost Comparison AkWarm Commercial Audit Software NSB Public Works Building Page 4 Rank Location Size/Type/Condition Recommendation Installed Cost Annual Energy Savings Air Leakage Rank Location Estimated Air Leakage Recommended Air Leakage Target Installed Cost Annual Energy Savings 2. Mechanical Equipment Mechanical Rank Recommendation Installed Cost Annual Energy Savings Setback Thermostat Rank Location Size/Type/Condition Recommendation Installed Cost Annual Energy Savings 5 First Floor Existing Unoccupied Heating Setpoint: 68.0 deg F Implement a Heating Temperature Unoccupied Setback to 60.0 deg F for the First Floor space. $200 $224 6 Second Floor Existing Unoccupied Heating Setpoint: 68.0 deg F Implement a Heating Temperature Unoccupied Setback to 60.0 deg F for the Second Floor space. $200 $218 Ventilation Rank Recommendation Cost Annual Energy Savings 1 change from "HAND" to "AUTO" $1 $6,571 3. Appliances and Lighting Lighting Fixtures and Controls Rank Location Existing Recommended Installed Cost Annual Energy Savings 7 Type H1 exterior 2 HPS 250 Watt Magnetic with Daylight Sensor Replace with 2 LED 115W Module StdElectronic $2,695 $77 8 Type G exterior 5 HPS 250 Watt StdElectronic with Daylight Sensor Replace with 5 LED 115W Module StdElectronic $6,736 $179 9 Type K exterior HPS 150 Watt Magnetic with Daylight Sensor Replace with LED 72W Module StdElectronic $900 $24 10 Type H exterior 4 HPS 100 Watt Magnetic with Daylight Sensor Replace with 4 LED 48W Module StdElectronic $3,600 $68 Refrigeration Rank Location Existing Recommended Installed Cost Annual Energy Savings Appenendix B Energy Audit – Energy Analysis and Cost Comparison AkWarm Commercial Audit Software NSB Public Works Building Page 5 Other Electrical Equipment Rank Location Existing Recommended Installed Cost Annual Energy Savings 2 Glycol pump speed 2 2 pump with Manual Switching Remove Manual Switching and Add new Other Controls $1 $841 3 Glycol pump speed 3 pump with Manual Switching Replace with pump $1 $252 4 Headbolt Heaters 36 Headbolt Heater with Other Controls Add new Clock Timer or Other Scheduling Control $20 $2,486 Cooking/Clothes Drying Rank Recommended Installed Cost Annual Energy Savings Appendix C: Equipment Schedules - Mechanical Appendix C: Equipment Schedules - Mechanical Appendix D: Building Plan Appendix D: Building Plan Appendix E: Lighting Plan Appendix E: Lighting Plan Appendix F: Mechanical Schematics Appendix F: Mechanical Schematics Appendix F: Mechanical Schematics Appendix F: Mechanical Schematics Appendix F: Mechanical Schematics