Loading...
The URL can be used to link to this page
Your browser does not support the video tag.
Home
My WebLink
About
Draft Makushin Interconnect Study 1996
")PROJECT NO.120402-01xwyLIESISSUEDTO: ENGINEERS COPY NO: DRAFT EXERGY,INC. MAKUSHIN INTERCONNECT STUDY OCTOBER,1996 Fi le.OssieFORINFORMATIONCONTACT:WM @ JOHN MCGREW ®RON BEAZER,P.E.Ov wot POWER ENGINEERS,INC.@ P.O.BOX 1066 @ HAILEY,IDAHO 83333 (208)788-3456 m@ FAX (208)788-2082 TABLE OF CONTENTS EXECUTIVE SUMMARY 1 "INTRODUCTION 6 SUMMARY 6 LOAD FLOW MODEL 8 RESULTS 9 MAKUSHIN INTERCONNECT 12 ALTERNATIVE 1:MAKUSHIN -MARGARET BAY INTERCONNECT ......ccscccsssscccocsescscsesesseecessnecceccescocceeaes 12 ALTERNATIVE 2 :MAKUSHIN -TOWN SUBSTATION INTERCONNECT......::scccccosccceccececccssccececcesscssecovsveess 16 INTERCONNECTED SYSTEM OPERATION 20 OPTION A:CITY WHEELING ..00..0....ccccccccccessceesesssessssessscceeceesaccuseesssersscccaccscscceuscesecasseccenscecacccseeesessoesees 20 OPTION B :INDEPENDENT SYSTEM OPERATOR (ISO).......ccccsssccsessesossscccssscoccessssesccoccosccoseorsecessssanecoccees 22 CENTRAL DISPATCH CENTER..........ccccccccscsesssessescsscccscsssccesecssssasesescssssessssessnsasscesaaceasecaccacesesseesesceee 27 UNISEA INTERCONNECTION 30 ALYESKA INTERCONNECTION 33 WESTWARD INTERCONNECTION 36 APPENDIX A 39 APPENDIX B 40 FIGURE 1 FIGURE 1A FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 TABLE 1 TABLE 2 TABLE 3 TABLE 4 TABLE 5 TABLE 6 TABLE 7 TABLE 8 TABLE 9 TABLE OF FIGURES AND TABLES Dutch Harbor/Unalaska Map Dutch Harbor/Unalaska Map with Alternate Interconnect Routes Alternative 1 -Makushin-Margaret Bay Interconnect Alternative 2 -Makushin-Town Substation Interconnect Makushin-Margaret Bay Interconnect One-Line Makushin-Town Substation Interconnect One-Line Unisea Substation Plan &One-Line Diagram Alyeska Substation Plan &One-Line Diagram Westward Substation Plan &One-Line Diagram Project Cost Summary Estimated Generation Schedule Margaret Bay Interconnection Cost Estimates Town Substation Interconnection Cost Estimates Wheeling Rates/Transmission Tariffs Filed with FERC Central Dispatch Center Cost Estimates Unisea Seafood Interconnection Cost Estimates Alyeska Seafood Interconnection Cost Estimates Westward Seafood Interconnection Cost Estimates ii EXECUTIVE SUMMARY This study was commissioned by Exergy,Inc.to evaluate three aspects of electric power production at the Makushin Geothermal Resourcefor 'sale to commercial customers in Dutch Harbor and the City of Unalaska. 1.Evaluate the requirements tottransmit approximately 15 megawatts (MW)of powerofUnalaska's 34.5kV transmission grid. 2.Determine the equipment required and estimate the constructed cost to extend the 34.5kV City electric system to Unisea Seafood,Alyeska Seafood and Westward Seafood processing plants and connect them to the grid. Evaluate the operation of the interconnected grid.Lv)Presently,the three fish processing plants self-generate their power requirements with diesel generators.The three plants have a combined load requirement of approximately 15.5MW during peak use.The City of Unalaska's power requirement is about 5.5MW peak demand and an average of 2,000,000kWh of energy supplied to consumers.With a rated output of ISMW,the Makushin Power Plant could supply 70%of the existing power requirements for the area.The potential fish processing customers have indicated that they would be willing to interconnect to the system if the power could be purchased for a lower cost than they can self-generate.The cost of power produced at the diesel plants and Makushin is not evaluated in this report. The results of the study show that a unified system grid can be constructed to serve the City and the three major fish processor loads with Makushin generating 14MW of the total system requirement. HLY 23-426 (10/26/96)120402-01/rh 1 Power flow analysis determined that 14MW of power can be transmitted from Makushin to the City grid with the proposed 34.5kV transmission line.With a 4/0 AWG copper conductor,the transmission losses are about IMW or 6%.Voltage regulation is required at the interconnect point with the City grid to control reactive power flows and voltage astheloadvaries.Fixed capacitors will be required at the'load centers to supply reactivepower,because generation of reactive power at Makushin-and transmission to thecustomerswouldresultinprohibitivelossesandvoltagedrop.Interconnect points wereevaluatedattheMargaretBaySubstationandattheCity's Town Substation,as showninFigures1and1A.The inter mmiect point does not significantly alter the power flow; therefore,the interconnect location should be selected based on economic and environmental considerations. From discussions with the City and Processor power plant staff,reliability of the power grid appears to be a significant concern.The City has recently completed a program to convert the electric system from overhead to underground.This has greatly improved the system reliability by reducing the exposure of the system to faults caused by wind and birds.To maintain this level of reliability,the interconnect station and power plant conceptual designs considered in this report use underground construction with enclosed tamper-proof equipment.The interconnect point with the Makushin 34.5kV line and the City grid will require a 38kV circuit breaker with directional (or distance)relaying,a 34.5kV voltage regulator with by-pass and disconnect switches,and metering.The preferred location for the interconnect is at Margaret Bay,based on the lowest cost. Interconnect substations for the fish processing plants are each comprised of a padmounted 34.5kV switch with fault protection,a 34.5kV junction box at the plant,a padmounted,fully-enclosed step-down transformer,and a fixed capacitor bank for reactive power support.Plant substations vary in cost depending on the line extension, transformer and capacitor sizes.Table 1 lists the estimated costs for each interconnect station. HLY 23-426 (10/26/96)120402-01/rh 2 Table 1:Project Cost Summary ITEM ESTIMATED |RECOMMENDED]ALTERNATE COST ($)SYSTEM (S$)SYSTEM ($) Alternative 1:Makushin -Margaret = Bay Interconnect 381,000}..-0 Alternative 2 :Makushin -Town eee Substation Interconnect 0 468,000 Unisea Seafood Substation = Interconnect 395,000 395,000 Alyeska Seafood Substation Interconnect :251,000 251,000WestwardSeafoodSubstationInterconnect:424,000 424,000Option1:Wheeling Contract”0 0 Option 2:Independent System Operator 696,000 0 696,000 TOTAL INTERCONNECT COST 1,451,000 2,234,000 Two methods available for operation of the interconnected system are Wheeling and Independent System Operator.Wheeling operation would only require a contract with the City of Unalaska to wheel the power over the existing lines to the customers.Each customer would contract for a demand load level from Makushin and self-generate their additional requirements.Changes in generation levels at Makushin would be requested over phone or radio by the customer.This system has very little initial cost,but it would incur monthly expenses to pay for capacity and losses. Independent System Operator (ISO)control would place the resources of all the power plants under the direction of an entity established to dispatch the generation based on economics.An ISO system would require installation of a computer system to monitor the generation and load and a communication system to transmit requests for generation increases or decreases.At this time,the Wheeling system is deemed to be the most desirable to reduce the initial project costs.The ISO system could be instituted at a later © date if desired. HLY 23-426 (10/26/96)120402-01/rh 3 HOG ISLAND UNALASKA BAY CAPTAINS BAY 8 16 MARGARET BAY SUBSTATION >INISEA SEAFOOD Si :canal. UNKER HILL 421 FT. WESTWOOD SEAFOOD MT.BALLYHOO 34 FT. LLIUTIUK ps DUTCH HARBOR LLIUTIUK BAY HARBOR DOWNTOWN UNALASKA ZA Town”@;SUBSTAILTO ne eae$"PYRAMID PEAK 2136 F FIGURE 1:DUTCH HARBOR/UNALASKA MAP UNAL ASKA BAY HIN VALLEYMAKUS LLTUTIUK BAY =SUBSTATION MARGARET BAY" BUNKER HILL CAPTAINS DEVILFISH POINT NATEEKIN BaY SKV ALTERNATIVE 2 mom wmeemown=CITY OF UNALASKA 34 a ALTERNATIVE 1 NIUTCH HARROR/UNALASKA MAPFIGCIIRE4A° INTRODUCTION In 1986,the Alaska Power Authority (APA)began investigating the feasibility of developing a geothermal resource to provide power to the community of Unalaska/Dutch Harbor on Unalaska Islandin the Aleutian Chain.The geothermal resource is located atthefootoftheMakushinvolcano,approximately.14 miles from Unalaska/Dutch Harbor. The past studies examined a/Makushin Power Plant output of about 7 megawatts (MW),which was assumed to be mainly sold to the City.Subsequent studies showed that for theprojecttobeeconomicallyfeasible,a Makushin output of approximately 1SMW would need to be connected to the City grid and also sold to the large fish processing customers, which presently self-generate. POWER Engineers,Inc.(POWER)was contracted by Exergy,Inc.to investigate the technical feasibility of interconnecting Makushin with the City and each of the three major fish processor plants to form one inclusive power grid.In this study,a field survey of the Unalaska system,as well as interviews with staff of City Powerhouse,Unisea Seafood, Alyeska Seafood,and Westward Seafood were conducted.(An interview summary is included in Appendix A.)Once the background information was collected,a computer model of the Unalaska power system was created and several load flow simulations were run to determine the facilities and operational requirements needed to support the complete system. SUMMARY The results of the study show that a unified system grid can be constructed to serve the City and the three major fish processor loads with Makushin generating 14MW of the total system requirement. HLY 23-426 (10/26/96)120402-01/rh 6 The system could be configured with a direct tie from Makushin to the existing City system.Under peak loading conditions,the City Powerhouse alone is unable to supply the remainder of the additional generation needed.The load flows indicate that additional fish processor power plant generation must be brought on-line to support the system at peakloadandtoprovideforspinningreserve.Due to.the compact nature of the electricalsystem,any of the three fish processor plants can supply this support.For more information,see Table 2 for a comparison of load versus generation. In addition to the need for local generation,power factor correction (i.e.shunt capacitor banks)will be required to minimize the need for reactive power generation at the load. The amount and location of power factor correction capacitors have been calculated to be: e Unisea 3600kvar e Alyeska 1800kvar e Westward 1800kvar An option that should be considered includes the addition of a 34.5kV voltage regulator at the interconnection point.This provides better voltage stability,as well as increased var transfer capability from Makushin.With this configuration,only one of the large city or processor plants would be required to be on-line during peak loading conditions. Under lightly loaded conditions,reactive support is still required from generation or fixed capacitors.Although the Makushin Plant has capacity to serve all of the load,low voltages will occur if the entire system var requirements are supplied by Makushin without power factor correction and voltage regulation. It should be noted that the fish processors use the waste heat from the generation exhaust to supplement heating.The final electrical load of the system may increase if the fish processor plants reduce their generation below levels required to produce the necessary heat. HLY 23-426 (10/26/96)120402-01/rh 7 The 4/0 copper cable from Makushin to the City will operate at approximately 80%of its rated capacity.Although this is acceptable,approximately 6%(1 MW)losses occur on the line.These losses could be reduced by using a larger cable... LOAD FLOW MODEL. The load flow program used for this study wwas PSS/E by Power Technologies,Inc.(PTI).This program allows''the.omodeling of looped systems with multiple generators. Assumptions used to create the model of the system are summarized below. e The system is configured with the Makushin interconnect to the city system at Margaret Bay. e The 34.5kV backbone was modeled with all loops connected. e The line from Makushin to Margaret Bay was modeled as 13.5 miles of underground 4/0 copper cable and 3.5 miles of 4/0 copper submarine cable. e All 34.5 kV conductors in the City grid were assumed to be 4/0 copper underground cable.The 12.47 kV line to Westward Seafoods was modeled as a 1/0 copper underground cable. e Load in the City was modeled by distributing load to each transformer location as a percentage of the total load as compared to the total connected system transformer capacity.Peak load in the City was assumed to be 5.5MW @ 0.95 p-f.,while off- season load was assumed to be 50%of the peak load. e Fish Processor loads are modeled as lump loads on the 4.16kV bus.Peak loads for each fish plant were assumed to be the following: *Alyeska:3.5 MW @ 0.85 pf. *Unisea:7.5 MW @ 0.85 pf. *Westward:45MW @ 085 pf. Off season loads for each of the fish plants were assumed to be 25%of the peak load. HLY 23-426 (10/26/96)120402-01/rh 8 e Fish Processor generators are modeled as being connected to the 4.16 kV bus at each plant. e When multiple generators at a bus were connected,the MW and Mvar of each individual generator were added together to form one equivalent generator. e Mukushin Generator: i *«14MW@O8pf. e City Plant Generators:.oan *LIMW@O08pf >*O6OMW@O8pE *LISMW@O08pf -*03MW@08pf *14]MW@O08pf.*03MW@08pf *0.62 MW @ 0.8 pf.*0.9MW @038 pf.(near the City Shop) *O83 MW@08pf£ Total =7.26 MW @ 0:8 pf. e Alyeska Generators: *2-20MW@O08pf£*1-15MW@O08pf. e Unisea Generators: *6-20MW@08pf. e Westward Generators: *3-212MW@08 pf. e The maximum generating MW of a generator was assumed to be its rated value.The maximum generated Mvar of a unit was assumed to be 0.7 times its rated MVA when the MW generated is less than or equal to 0.4 times its rated MVA. RESULTS A base case was run to demonstrate that the existing system is acceptable with all City load being supplied by the City Powerhouse.This case was run with all the fish HLY 23-426 (10/26/96)120402-01/rh 9 processors removed and Makushin not connected to the City grid.The results from this case showed that system is operating within acceptable industry limits. Next,simulations were performed with Makushin and the fish processors connected to the grid.For these cases,the generator at Makushin was assumed to operate at full capacity and the City Powerhouse would make up necessary additional generation.When these cases were run,low voltages occurred throughout the system,and the City Powerhouse was not capable of supplying all of the additional generation required.In order for the system to operate within constraints,a minimum of two fish processor generators would need to be on-line to supply the additional generation and maintain a 20%spinning reserve margin.The additional generation required from the fish processor plants is largely driven by the need for system var support.In particular,the 85%power factor assumed for the fishery loads requires a large amount reactive power generation.As such,power factor correction will need to be implemented for the system to be operational without multiple city/processor generators on-line. Due to the compact nature of the system grid,it does not make a large difference which processors have generators on-line.In addition to the need for additional reactive power support,a direct 34.5kV feed was added from the Town Substation to Westward Seafood for voltage drop correction.Also,the tap settings of the transformers at Makushin,the City Power Plant,Alyeska,Unisea,and Westward had to be adjusted for voltage support. Further case studies were performed with the addition of a 34.5kV voltage regulator installed on the interconnect point at Margaret Bay.This allows for greater voltage stability as well as increased var support from the Makushin Power Plant.Thus,the addition of the voltage regulator allows the system to operate with only one fish processor generation plant on-line for a majority of the peak loading conditions. For comparison purposes,the following table shows the total system load versus the required generation to support the load and provide for spinning reserve.This table HLY 23-426 (10/26/96)120402-01/rh 10 assumes that the load power factors are corrected to 0.95 lagging such that the generation on-line can support the system var requirement. Table 2:Estimated Generation Schedule Combined]Spinning |Total Gen.|Makushin City Fish Proc. Load Reserve |Required }Output Output |2 Output 21.00 5.20 26.20}814.00]-7.26 4.94 19.00 4.80 23.80 14.00 7.26 2.54 17.00 4.40]-21.40]»14.00 7.26 0.14 15.00}=4.00]=19.00 14.00 5.00 0.00 13.00]=3.60 16.60 14.00 2.60 0.00 11.00]°"3.20 14.20 14.00 0.20 0.00 Notes: 1.All values in MW 2.Load power factor at 0.95 lag 3.System losses =1MW (includes 0.8MW for Makushin -City line) HLY 23-426 (10/26/96)120402-01/rh 11 MAKUSHIN INTERCONNECT The Makushin Geothermal Project has two possible interconnect points to the Unalaska- Dutch Harbor 34.5kV electrical grid.The best interconnect for the proposed line route from Makushin to Amaknak Island would terminate at or near the Margaret Bay Substation.One additional interconnect that would have significant benefit,would be to terminate at the Town Substation located on Unalaska Island across from City Hall. Advantages,disadvantages,'conceptual design and conceptual cost estimates for each alternative are discussed below. ALTERNATIVE 1:Makushin -Margaret Bay Interconnect This interconnect assumes the most desirable 34.5kV transmission route from the Makushin Geothermal Plant.The undersea cable would terminate on Amaknak Island near the intersection of Airport Beach Road and East Point Road.This is the present location of the City's Margaret Bay Substation,which consists of a 34.5kV pad-mounted switch and a 1500kVA,34.5-12.47kV pad-mounted transformer. The power flow analysis indicated that a 34.5kV voltage regulator would be required to match the line voltage to the City grid voltage.This limits reactive power production by the City /Processor generation plants and allows the Makushin Plant to provide service at a steady voltage regardless of load swings.The conceptual installation,as shown in Figures 3 and 4,consists of a 38kV circuit breaker,a meter/relay cabinet;a regulator by- pass/disconnect,a 38kV switch;a 34.5kV,340 ampere,2000kVA,+/-10%,three-phase voltage regulator;and a second 38kV regulator by-pass/disconnect switch with an additional line terminal.All equipment for this location is assumed to be padmounted with tamper-proof enclosures.Cable between apparatus would be single conductor,4/0 AWG, copper,TRXLP cable.Terminations to equipment would be Elastimold,34.5k,600 ampere elbows for dead-front construction.Since the apparatus is proposed to be pad- HLY 23-426 (10/26/96)120402-01/rh 12 mounted,the layout can be designed to best fit the available site.The site could be on either side of the Airport Beach Road. Advantages: e Shortest 34.5kV cable length. e Pad-mount design will reduce outages due to weather. e Lowest cost. e Shortest distance to the largest load center. Disadvantages: e Requires installation of the station in an existing parking lot or on bare ground across the road. Estimated Constructed Cost =$381,000 HLY 23-426 (10/26/96)120402-01/rh 13 CITY POWERHOUSE aquva 4.36/72.4KV34.5719.92K¥7.26ee0MUKUSHINMUKUSHIN-MARGARET ,00.804 GEOTHERMAL PLANT BAY INTERCONNECT CI 3£r}PT a eee me 7 3¢ | |||in 3f||aa r--A |3 1aNw 3 |aro cuu_}UNDERSEA |-ae |iA.|.° | 4/0 CU UG 470 CuU_UG auva -L470 CU UG UNDERSEA -_---_---_}$-_---1/0 CU YGe.08pf \ 7)+r 3 Tj 71.280%t 7 %8.480ft Ter oT q vay r T }7 Toft 4.600ft i182.any |ad _ee=ao _-_|||"T ||1 | ||-_-_-_-4 bo i |e-_-----_>OO }|alg Sir |t 4 en oe MARGARET BAY * SUBSTATION 4/0 CU UG 470 CU UG 3.720ft 3.408ft UNISEA <SEAFOOD =vam aaL_S ( )@0.6pf gis --=)FAREEEI gee -ror aA 7.5uva +-_{_}->"Cocespt|\n |34.5/12.47TKV |-;|T |iz ! |f a _|gl+ALYESKA as sum -SEAFOOD ole00.8pf }LJ > ;p---or aory3.5m peak g___f}_sas ||nf ..T5MVA --_-'-memset 34.5712.47KV rT |1 LS |roy TT _ PV \1;EY\||"4eeneaccac|})| i 1 _'|WESTWARD TOT gh.TOWN|SEAFOOD als SUBSTATION 6.36My rget()--4 .a|i,-Tease)FS ae ay 'a (+4$--o- 4.5MW peak ¢-«@0.85pf :5.0MvA 3.75uva |34.5/12.47KV rm__3£rmUF 3.75MVa FIGURE 2:ALTERNATIVE 1 MAKUSHIN -MARGARET BAY INTERCONNECT Table 3:Margaret Bay Interconnection Cost Estimates ITEM DESCRIPTION SHIPPING LABOR L&M QUANTITY EXTENDED WEIGHT COST HOURS |UNIT |EXTENDED 1 Switch,4"Way,38kV,Pad mount,2 BA 700 $420 20}$200 $8,000 $32,420Tamper-proof enclosure.mae 2 35kV Regulator,3-phase,340A 1 EA $120,000 12000 $3,600 32]$200 $6,400 $130,000 Meter/Relay Unit,38kV,Pad mount, Tamper-proof enclosure,CTR 300:5" 3 |(one set meter accuracy,one set relay |$35,000 $35,000 1500 $450 24]$200 $4,800 $40,250accuracy),PTR 170:1(meter accuracy); complete with bi-dir¢ctional meter,and two directional overcurrent relays. ircui i 0).,Padgq [2°KV Circuit Dreher ©OA Cont,Pa 1 EA |$30,000 $30,000 5000 $1,500 241 $200 $4,800 $36,300 5 Cable,34.5kV,4/0 Cu,TRXLP 270 FT $7.5 $2,025 3 $243 1 $8.0 $2,160 $4,428 6 Site Work and Grading 1 LOT $2,000 $2,000 0 $0 32 $200 $6,400 $8,400 7 Foundations,Regulator 45 CUYD $100 $450 0 $0 4.5}$200 $4,050 $4,500 8 Foundations,Switch /Brkr 5.4 CU YD $100 $540 0 $0 5.4|$200 $5,832 $6,372 9 Misc.Parts 1 LOT $10,000 $10,000 1000 $300 24;$200 $4,800 $15,100 Cable Elbows 30 EA $250 $7,500 250 $2,250 0.5 $200 $3,000 $12,750 .$0 Subtotal Labor and Material $290,520 Design and Construction Management (16%of L&M)$46,483 Contingency (15%)$43,578 Total Estimated Constructed Cost $380,581 HLY 23-426 (10/26/96)120402-01/rh 15 ALTERNATIVE 2:Makushin -Town Substation Interconnect To establish the interconnect at the Town Substation,the 34.5kV transmission route from the Makushin Geothermal Plant would require a slight alteration,which would be finalized during design.For this conceptual termination,the undersea cable would make landfall near the intersection of Gilman Road and Airport Beach Road.The 34.5kV circuit would then be routed along Airport Beach Road into the Town Substation as shown in Figures 5and6.Conduit would be attached to the underside of the Bridge -to-the-Other-Side for the cable.©| A 38kV padmount switch would be installed at the undersea/underground transition point to allow cable termination and circuit sectionalizing.The circuit would enter the Town Substation yard,terminate on a three-phase,34.5kV voltage regulator (complete with a padmount by-pass/disconnect switch)and then terminate on an indoor class 38kV switchgear breaker.There is space available in the substation control building for additional sections of 38kV indoor switchgear.We would expect the breaker cubicle to be equipped with metering,relaying and synchronizing apparatus. As with the Makushin -Margaret Bay Interconnect (Alternative 1),a 34.5kV voltage regulator would be required to match the line voltage to the City grid voltage and limit reactive power production by the City /Processor generation plants.Cable between apparatus would be single conductor,4/0 AWG,copper,TRXLP cable.Terminations to equipment would be Elastimold,34.5k,600 ampere elbows for dead-front construction. Since the apparatus is proposed to be pad-mounted,the layout can be designed to best fit the available site.The site could be on either side of the Airport Beach Road. Advantages: e Shortest 34.5kV undersea cable length. e Padmount design will reduce outages due to weather. HLY 23-426 (10/26/96)120402-01/rh 16 e Indoor substation installation allows for synchronizing at the Unalaska end of the circuit. e Less impact to environment due to installation in an existing electrical yard. Disadvantages: e Requires installation of approximately 6,000 feet of additional 34.5kV underground cable./Le e Highest Cost Estimated Constructed Cost =$469,000 HLY 23-426 (10/26/96)120402-01/rh 17 CITY POWERHOUSE aMva 4.1672.4K34.5719.92K¥|Tt (-)2a0.8pt -EO ee -3e auva4/70 CU _UG 4/90 CU UG loft 4.600fF 4.16/72.4KV34.5719.92KV MARGARET BAY ;SUBSTATION4/0CUUG1OFt4/0CU_UG5.-992Ft4/0 CU UG 470 CU_UG 3-720ft 3.408ft UNISEA «SEAFOOD =lowe sicaLI( )00.8p e2i3=470 cuUG_(2)_600KCM CU)SE "eocrs1 [--4||7.5MW peakr-hro}-7 7.SMVA }--L}-_>€0.85pfi\|34.5712.47KV \\+i r -||i ae |ALYESKA 4/0CUUG200ft-600KCmM Cu -™4/0 CU UG|eeeeen Ml meee.vj [7 "Toort -- | sum = SEAFOOD :0.8pt ( )LSI <3.5MW¥peok <{q@0.85pf 3.75NVa -A34.5/12.47KV '?| |acaTT4 _- 1 \|»LY ||ne ||| __'_1 _|WESTWARD TT 3.TOWN |SEAFOOD als SUBSTATION +els ee "assis [}+-}/-1} 5.0MVA MUKUSHIN 3.75MVA 3405712.47KN GEOTHERMAL PLANT ee '[-_-7\"- ]|'Ce |-I-==4-i 1 ||/= __7 470 Cu a oo |\\}-_ra 3 £m1T4uw2|es0spe (2 =--=0F GE Th Veseote”+Ypesostt -EE aigo Spt LI ¢-_r||-- --!---3.75MVA |OO :FIGURE 3:ALTERNATIVE 2 MAKUSHIN -TOWN SUBSTATION INTERCONNECT Table 4:Town Substation Interconnection Cost Estimates ITEM DESCRIPTION MATERIAL SHIPPING LABOR L&M QUANTITY UNIT |EXTENDED WEIGHT COST HOURS |UNIT |EXTENDED 1 Switch,3-Way,38kV,Pad mount,2 EA |$12,000 $24,000 700 $420 20}$200 $8,000 $32,420Tamper-proof enclosure. 2 35kV Regulator,3-phase,340A 1 EA $120,000 $120,000 12000 $3,600 32|$200 $6,400 $130,000 3 Meters and Relays 1 EA $15,000 »$15,000 1500 $450 2|$200 $400 $15,850 4 35kV Circuit Breaker,1200A,Indoor 1 EA $30,000 $30,000 5000 $1,500 24|$200 $4,800 $36,300 5 Cable,34.5kV,4/0 Cu,TRXLP 6000 FT $7.5 $45,000 3 $5,400 1 $8.0 $48,000 $98,400 6 Site Work and Grading }LOT «$2,000 $2,000 0 $0 32|$200 $6,400 $8,400 7 Foundations,Regulator 4.5 CU YD $100 $450 0 $0 4.5 $200 $4,050 $4,500 8 Foundations,Switch /Brkr 3.6 CU YD $100 $360 0 $0 5.4 $200 $3,888 $4,248 9 Misc.Parts 1 LOT $10,000 $10,000 1000 $300 24,$200 $4,800 $15,100 Cable Eibows 30 EA $250 $7,500 250 $2,250 0.5}$200 $3,000 $12,750 $0 Subtotal Labor and Material $357,968 Design and Construction Management (16%of L&M)$57,275 Contingency (15%)$53,695 Total Estimated Constructed Cost $468,938 HLY 23-426 (10/26/96)120402-01/rh 19 INTERCONNECTED SYSTEM OPERATION With the electrical system interconnected with multiple points of generation and load, there will be a requirement for an entity to control operation of the system.Two main options are available to operate the system:wheel power over the City grid to the loads or establish an Independent System Operator (ISO). OPTION A:City Wheeling This option requires no capital investment.To operate under this option,each customer (City or processor)would contract with Makushin to purchase energy (kWh)and demand capacity (kW).The energy and demand would be measured at the interconnect point with the city grid.Makushin and the City of Unalaska would negotiate a "Wheeling Contract” rate for transmission line capacity based on demand,and a loss charge based either on demand or energy.Metered losses would be difficult to meter due to the interconnected system.Generally,there are two established methods to compensate for losses after the losses for the contract are agreed upon: 1)The Makushin generator could deliver the additional energy to the City interconnect meter point to compensate for the losses. 2)Makushin could pay the City a negotiated monetary rate to compensate for the City supplying the losses from the City Power Plant. System operation would be based on telephone or radio communications between plant operators.Each Makushin customer would contract for a block of power to be provided from Makushin.Remaining power requirements would be either generated internally or HLY 23-426 (10/26/96)120402-01/rh 20 purchased from another plant.As load changes occur,the plant operators would need to contact the Makushin operator to adjust the geothermal plant generated output. For example,Unisea Seafood could contract for SMW of demand.Assume that the load is at 2MW,and one Unisea generator is on-line.Load is increasing as the plant resumes production.The Unisea operator contacts the Makushin operator to coordinate the generation mix as the load increases,bringing the Unisea generator to near peak output and then transferring the load to Makushin.Once their load exceeds the SMW contract, Unisea would supplement the Makushin power with additional Unisea diesel generators. Each processing plant would need to keep at least one unit on-line to provide reactive power,load following and spinning reserve.The optimum situation would be to have the total 1SMW Makushin Geothermal Plant (minus losses)output under contract and utilized,considering it as the least cost power alternative,with each customer then generating their own additional requirements. Wheeling rates are the result of negotiations between the parties and are often based on capital and O&M costs of the lines being used with respect to the percentage of line capacity being reserved for the wheeled power.Table 5 illustrates examples of wheeling tariffs submitted to the Federal Energy Regulatory Commission (FERC)based on the guidelines of the Open Access Notice of Proposed Rule-making by several major utilities. Loss charges generally range from 3 to 6 percent of average demand.We should keep in mind that these figures are for major utilities with significant capital investments in transmission facilities.We also must note that the City of Unalaska does not fall under FERC since the facilities do not cross state lines. HLY 23-426 (10/26/96)120402-01/rh 21 Table 5:Wheeling Rates/Transmission Tariffs Filed with FERC Utility Point-to-Point Network Losses (S/kW-MO)_|($/kW-MO) WWP $1.55 $1.74 3.00% SPPCo $3.16 $3.47 3.25% BPA $1.32 $1.60 oss PP&L $2.79 ---- WAPA $1.88 $1.88 6.00% Advantages: e Least requirements for personnel and equipment e Lowest initial capital cost e Easiest system to implement e Processor plants diesel generation is available and on-line in case of a grid or Makushin Power Plant outage Disadvantages: e Does not take advantage of economic dispatch e Wheeling charges increase the power cost Estimated Constructed Cost =$0 OPTION B :Independent System Operator (ISO) This option requires that the City of Unalaska participates as a customer for Makushin power in addition to the fish processors.A central dispatch center would be constructed to house the dispatch computer and communications system operated by the Independent System Operator (ISO).All generators would be evaluated for economics of production and assigned a ranking.The central dispatch center would monitor load and generation with a Supervisory Control and Data Acquisition (SCADA)system.As demand increased HLY 23-426 (10/26/96)120402-01/rh 22 to near 80 percent of the on-line machine capacity,the next least power cost generator would be brought on-line.Conversely,as load decreases,the next highest power cost generator would be taken off-line and shut down.Thus,the power for all customers would be produced at the least cost,which would be reflected in the power rates. We assume that four personnel would be required as ISO staff to man the central dispatch 24 hours a day.These personnel couldbe hired specifically for this task,or they could be assigned operators from the various power plant staffs.This is a decision that would be determined at the time that the power contracts are negotiated. At this time,ISO control of the generation resources is not considered.Each plant would physically control and operate the machines under the direction of the ISO dispatcher.For example,assume the system load is at 13MW and Makushin is at full output.Two Unisea diesel generators are on-line.The load begins to increase to 22MW.The ISO determines that two additional generators will need to be committed to meet the system requirements. The ISO calls the Unisea and City plant operators and requests the generators be started and connected to the line.As the load increases,the ISO contacts the plant operators by phone or radio to request machine kW and kvar loading to meet the system needs.This example assumes that an economic analysis determined that the Unisea diesel units are the next most economical machines until the fourth unit is committed.The fourth unit carries an air quality penalty,which results in one of the City's machines being the next least cost. During POWER's field visit,two locations were determined to be available for a central dispatch center.The upper story of the City Power Plant and the Unisea Power Plant control room are each candidates for a central dispatch center.An area of approximately ten feet by 12 feet would be adequate for the control console and communications equipment. HLY 23-426 (10/26/96)120402-01/rh 23 Advantages: e Processor plants diesel generation is available and on-line in case of a grid or Makushin Power Plant outage e Energy would be provided at the least cost Disadvantages: e Requires installation of a.central dispatch center and communication system as described below Estimated Constructed Cost =$696,000 HLY 23-426 (10/26/96)120402-01/rh 24 34.5KV PAD MOUNT METERING UNST [_- ory | NEW CONTRUCTION |EXISTING | | | | 34.5KVHotes6004 |oa wt =34.5KY TO CITYOs|ne rae eaW.0.|N.C.|N.C N Ce BEACH RD) | | REGULATOR BY-PASS/| DISCONNECT | r----4 |34.5KY TO CITY POWER PLANT/ CHANNEL CROSSING (EAST POINT RD) 34.5KYTOSUBSTATION he 12.47KV MARGARET BAY SUBSTATION NEW CONTRUCT ION EXISTING FIGURE 4:MAKUSHIN -MARGARET BAY INTERCONNECT ONE-LINE NEW CONTRUCTION |EXISTING ALYCHANNEL 34.5KY TOE vo\|MAKUSHIN:J}|SS eee ee eeepour|LJ 300:5 J00:5 EQUIPMENT MOUNTED IN SWITCHGEAR AT TOWN SUBSTATION 1 3LJ3 34.5KY TO WESWARD SEAFOOD/ UNISEA FIGURE 5:MAKUSHIN -TOWN SUBSTATION INTERCONNECT ONE-LINE CENTRAL DISPATCH CENTER The communications portion of the project would use 450Mhz radio,six-channel capability equipment.One channel would be used for SCADA to a centralized dispatch point.The second channel would be used for voice communications. Two radio repeater sites would be used in the system.One site would be located in the Dutch Harbor area where radio sites already exist,and the other would be on the route of the 34.5kV underground cable at a point where there is line-of-site to the repeater at Dutch Harbor (this second site may not be required).POWER recommends that the repeater site on the 34.5kV be powered from a transformer feed from the 34.5kV line, since solar power would not be an effective means of supplying the repeater site.A small diesel generator is also recommended. Standard radio sites would be located at the three fish processing plants with auxiliary generation,at the City's power plant and at the proposed site of the geothermal generation. The SCADA system would use the radio system to monitor the generation and load at the three fish processing plants,the City's power plant and at the proposed geothermal generation plant.The information would be collected via Programmable Logic Controllers (PLC)located at each of the five sites.The Human Machine Interface (HMI) would be located at a site to be determined later.The HMI would consist of a Personal Computer (PC)and two workstations (one for the operator and the other for configuration).The HMI would be located close to one of the standard radio sites. The telephone system would use the radio system to provide communications to all sites. This would allow for dispatching of power for all generation facilities.The telephone HLY 23-426 (10/26/96)120402-01/rh 27 system would also provide communications for troubleshooting the SCADA system and for restoration of power coordination to the Dutch Harbor area. Other communications media such as microwave radio or fiber optics were considered but were determined to be too costly for this application given the construction constraint at the physical location of the system. HLY 23-426 (10/26/96)120402-01/rh 28 Table 6:Central Dispatch Center Cost Estimates ITEM DESCRIPTION MATERIAL LABOR L&M QUANTITY UNIT |EXTENDED |WEIGHT FREIGHT |HOURS |UNIT}EXTENDED Master Station including dual MMI,PC 1 processor,software,modem,1 EA |$20,000 ©$20,000 300 $90 40 $200 $8,000 $28,090 installation,and field testing Master configuration and system testing)gy |g $0 700 $0 go |sas $6,800 $6,800(at factory) 2 |Radio equipment including radio,coax)$150,000 1000 $300 50 |$200 $10,000 $160,300antenna,tower,and installation Radio equipment startup andtesting |0.EA $0 $0 0 $0 40 |$200 $8,000 $8,000 Radio repeater equipment including 3 radios,battery bank,charger,coax,2 EA |$65,000 $130,000 4000 $1,200 120 |$200 $24,000 $155,200antennas,building,tower,and installation Radio repeater equipment startupand |eA |go $0 0 $0 40 |$200 $8,000 $8,000testing PLC equipment including softwware,4 modem,installation,and field testing 5 EA $10,000 $50,000 1000 $300 100 $200 $20,000 $70,300 PLC configuration and system testing 0 EA $0 $0 0 $0 80 $85 $6,800 $6,800(at factory) iz ite at h6ConcretepadoesiteatDutc!2 EA $3,000 -$6,000 $0 32 $200 $6,400 $12,400 6 _|Concrete pad for repeater site widiesel |=5 ea |gs 009 $10,000 $0 32 |$200 $6,400 $16,400generator 7 Diesel Generator 1 EA $30,000 $30,000 $0 32 $200 $6,400 $36,400 8 Startup Support 1 LOT |$15,000 $15,000 $0 80 $100 $8,000 $23,000 Subtotal Labor and Material $531,690 Design and Construction Management (16%of L&M)$85,070 Contingency (15%of L&M)$79,754 Total Estimated Constructed Cost $696,514 HLY 23-426 (10/26/96)120402-01/rh 29 UNISEA INTERCONNECTION Figure 6 illustrates the conceptual interconnection for Unisea Seafood Power Plant.The existing junction box (T-1)at the intersection of Airport Beach Road and Salmon Way would be replaced with a new 35kV padmount switch (SW-UNISEA).This switch would have solid blades to both Margaret Bay and Town Substation,and fused disconnects to Petro Mart and Unisea Seafood Power Plant.The connection to Margaret Bay,Town Substation and Petro Mart would use existing 35kV cable.The connection to Unisea would require new 35kV cable from the switch (SW-UNISEA)to junction box M-2 and use existing 35kV cable from M-2 to Unisea Seafood Power Plant. At Unisea Seafood Power Plant,the 35kV cable would be terminated on a new 35kV, 600A junction box,which would have a fused connection to a new 7.5/1OMVA,34.5- 4.16kV transformer.A capacitor bank would be connected from the 4160V secondary of the transformer. The power plant has an existing 4160V breaker cubicle with synchronizing equipment, metering and relaying.A negative sequence voltage relay may be required for detection of single-phase and two-phase conditions due to a fuse operation.In the event of such a condition,the relay would operate the breaker. Cost estimates for the interconnection are tabulated in Table 7. HLY 23-426 (10/26/96)120402-01/rh 30 UNISEA SE AF 00D POWER PLANT ol|GILMAN ROAD EXISTING PLAN UNISEA SEAFOOD POWER PLANT SWITCH GEAR GILMAN ROAD RECOMMENDED PLAN EXISTING 34.5KV EXISTING 34.5KV|| TO TOWN SUB ||TO MARGARET BAY || |EXISTING TO|el PETRO MART| 34.5KV 4/0 IoSW-UNISEAUGCABLE-D (REPLACES EXISTING(EXISTING)T-1 JUNCTION BOX) JUNCTION BOX ALN 34.5-4.16KV CYS 1.5/1 0MVA ||||||||4Pom NT||=UNISEA 9 '--ear gncSEAFOODPOWER PLANT UNISEA SUBSTATION PLAN &ONE-LINE DIAGRAMFIGURE6: Table 7:Unisea Seafood Interconnection Cost Estimates ITEM DESCRIPTION MATERIAL SHIPPING LABOR L&M QUANTITY UNIT EXTENDED WEIGHT COST HOURS |UNIT |EXTENDED 1 Switch,4 Way,38kV,Pad mount,1 EA $12,000 $12,000 700 $210 40|$200 $8,000 $20,210Tamper-proof enclosure 2 Transformer 3pase TOON A 1 EA |$75,000 $75,000 50000]$15,000 40]$200 $8,000 $98,000 3 Junction box,35kV 1 EA $7,500 $7,500 1500 $450 16]$200 $3,200 $11,150 4 Fault Interrupter,35kV 1 EA $20,000 $20,000 1500 $450 16|$200 $3,200 $23,650 5 Capacitor Bank,3.6MVAR,4160V,1 'EA<|©$12,000 $12,000 3000 $900 32]$200 $6,400 $19,300withFiltersae: 6 |Rotaying,Metering,CTs/PTs,4160V 1 LOT $8,500 $8,500 500 $150 16|$200 $3,200 $11,850 7 Cable,34.5kV,4/0 Cu,TRXLP 5000. -FT $5 $25,000 4 $6,000 0.032]$200 $32,000 $63,000 8 Conduit,4"5000. -FT $0.1 $500 4 $6,000 0.016]$200 $16,000 $22,500 9 Site Work and Grading 1 LOT $2,000 $2,000 0 $0 40|$200 $8,000 $10,000 Foundations,Switch /Transformer / 10 Junction Box /Vacuum Fault 8 CUYD $275 $2,200 500 $1,200 5}$200 $8,000 $11,400 Interrupter/Capacitor ll Misc.Parts 1 LOT |$10,000 $10,000 1000 $300 $200 $0 $10,300 Subtotal Labor and Material $301,360 Design and Construction Management (16%of L&M)$48,218 Contingency (15%of L&M)$45,204 Total Estimated Constructed Cost $394,782 HLY 23-426 (10/26/96)120402-01/rh 32 ALYESKA INTERCONNECTION Figure 7 illustrates the conceptual interconnection for Alyeska Seafood Power Plant.The existing junction box (TL-1)would be replaced with a new 35kV padmount switch (SW- ALYESKA).This switch would have solid blades to.both Margaret Bay and Town Substation,and a fused disconnect to Alyeska Seafood Power Plant.The connection to Margaret Bay and Town Substation would use existing 35kV cable.The connection toAlyeskawouldrequireapproximately1000feetofnew35kVcablefromtheswitch(SW- ALYESKA)to a new junction box located at Alyeska. At Alyeska Seafood Power Plant,the 35kV cable would be terminated on a new 35kV, 600A junction box,which would have a fused connection to a new 3.75MVA,34.5- 4.16kV transformer.A capacitor bank would be connected from the 4160V secondary of the transformer. The power plant has an existing 4160V breaker cubicle with synchronizing equipment, metering and relaying.Approximately 400 feet of 4160V cable in tray would be required from the transformer to the breaker.A negative sequence voltage relay may be required for detection of single-phase and two-phase conditions due to a fuse operation.In the event of such a condition,the relay would operate the breaker. Cost estimates for the interconnection are tabulated in Table 8. HLY 23-426 (10/26/96)120402-01/rh 33 WESTWARD SEAFOOD POWER PLANT SWITCH GEAR HARBOR -|---Lae/BRIDGE TO THE WESTWARD SEAF OOD JUNCTION BOX NEW 34.5KV 4/0 CABLE -- APPROX.7000' TO MARGARET BAY EXISTING 34.5KV LINE | | !TO | | TOWN34.5KV LINE SUB. SW-WESTWARD ALYESKA SUBSTATION PLAN &ONE-LINE DIAGRAM FIGURE 7:. Table 8:Alyeska Seafood Interconnection Cost Estimates ITEM DESCRIPTION MATERIAL SHIPPING LABOR L&M QUANTITY UNIT |EXTENDED WEIGHT COST HOURS |UNIT |EXTENDED 1 Switch,4 Way,38kV,Pad mount,1 EA |$12,000 $12,000 700 $210 40|$200 $8,000 $20,210Tamper-proof enclosure 2 __|Transformer,aad MVA,34.5-)EA |_$40,000 -$40,000 28000 $8,400 40]$200 $8,000 $56,400 3 Junction box,35kV 1 EA $7,500 $7,500 1500 $450 16 $200 $3,200 $11,150 4 Vacuum Fault Interrupter,35kV 1 EA $20,000 $20,000 1500 $450 16 $200 $3,200 $23,650 5 Capacitor Bank,1.8MVAR,4160¥V,1 EA |=.$7,500 $7,500 2400 $720 32|$200 $6,400 $14,620withFilters ie 6 Relaying,Metering,CTs/PTs,4160V.I Sa,LOT $8,500 $8,500 500 $150 16 $200 $3,200 $11,850 7 Cable,34.5kV,4/0:Cu,TRXLP 1000 FT $5 $5,000 4 $1,200 0.032 $200 $6,400 $12,600 8 Conduit,4"1000 FT $0.1 $100 4 $1,200 0.016}$200 $3,200 $4,500 9 Site Work and Grading 1 LOT $2,000 $2,000 0 $0 40 $200 $8,000 $10,000 Foundations,Switch /Transformer / 10 Junction Box /Vacuum Fault 8 CU YD $275 $2,200 500 $1,200 5 $200 $8,000 $11,400 Interrupter/Capacitor 11 |Cable,4160V,oi Cu,ineable |499 FT $5 $2,000 4 $480 0.032]$200 $2,560 $5,040 12 Misc.Parts 1 LOT $10,000 $10,000 1000 $300 $200 $0 $10,300 Subtotal Labor and Material $191,720 Design and Construction Management (16%of L&M)$30,675 Contingency (15%of L&M)$28,758 Total Estimated Constructed Cost $251,153 HLY 23-426 (10/26/96)120402-01/rh 3 5 WESTWARD INTERCONNECTION Figure 8 illustrates the conceptual interconnection for Westward Seafood Power Plant.A new 35kV padmount switch (SW-WESTWARD)would be located at the intersection of Airport Beach Road and Captains Bay Road.This switch would have solid blades to both Margaret Bay and Town Substation,and a fused disconnect to Westward Seafood Power Plant.The connection to Margaret Bay and Town Substation would use existing 35kV cable.The connection to Westward would require approximately 7000 feet of new 35kV cable from the switch (SW-WESTWARD)to a new junction box located at Westward. At Westward Seafood Power Plant,the 35kV cable would be terminated on a new 35kV, 600A junction box,which would have a fused connection to a new 5MVA,34.5-4.16kV transformer.A capacitor bank would be connected from the 4160V secondary of the transformer. The power plant has an existing 4160V breaker cubicle with synchronizing equipment, metering and relaying.Approximately 1000 feet of 4160V cable in tray would be required from the transformer to the breaker.A negative sequence voltage relay may be required for detection of single-phase and two-phase conditions due to a fuse operation.In the event of such a condition,the relay would operate the breaker. Cost estimates for the interconnection are tabulated in Table 9. HLY 23-426 (10/26/96)120402-01/rh 36 HARBOR ALYESKA SE AF OOD POWER PLANT cap,SWITCHGEAR meanSs1 N XF MR TO MARGARET BAY EXISTING 34.5Kv4 UNDERSEA CABLE | J,TO {_;--=TOWN Swe SUB. ALYESKA SEAF 00D TO MARGARET BAY | | 4 t||Po |TO JUNCTION BOX :TOWN | !SUB. SW-ALYESKANEW34.5KV 4/0 CABLE - (repr ACES EXISTINGAPPROX.1000' FIGURE 8: TL-1 JUNCTION BOX) WESTWARD SUBSTATION PLAN &ONE-LINE DIAGRAM Table 9:Westward Seafood Interconnection Cost Estimates ITEM DESCRIPTION MATERIAL SHIPPING LABOR L&M QUANTITY UNIT EXTENDED WEIGHT COST HOURS |UNIT |EXTENDED 1 Switch,4 Way,38kV,Pad mount,1 EA |$12,000 $12,000 700 $210 40|$200 $8,000 $20,210Tamper-proof enclosure 2 Transformer,ee oMVA,34.5-1 EA |_$60,000 $60,000 35000]$10,500 40]$200 $8,000 $78,500 3 Junction box,35kV 1 EA $7,500 $7,500 1500 $450 16|$200 $3,200 $11,150 4 Fault Interrupter,35kV 1 EA $20,000 $20,000 1500 $450 16}$200 $3,200 $23,650 5 [Capacitor Bank,a 4160V with)|EA $7,500 $7,500 2400 $720 32}$200 $6,400 $14,620 6 Relaying,Metering"CTs/PTs,4160V 1 LOT $8,500 $8,500 500 $150 16}$200 $3,200 $11,850 7 Cable,34.5kV,4/0 Cu,TRXLP 7000 FT $5 $35,000 4 $8,400 0.032]$200 $44,800 $88,200 8 Conduit,4”7000 FT $0.1 $700 4 $8,400 0.016]$200 $22,400 $31,500 9 Site Work and Grading 1 LOT $2,000 $2,000 0 $0 40]$200 $8,000 $10,000 Foundations,Switch /Transformer / 10 Junction Box /Vacuum Fault 8 CUYD $275 $2,200 500 $1,200 5|$200 $8,000 $11,400 Interrupter/Capacitor 11 |Cable,4160V,5 aaa Cu,incable |ioog ET $5 $5,000 4 $1,200 0.032]$200 $6,400 $12,600 12 Misc.Parts 1 LOT |$10,000 $10,000 1000 $300 $200 $0 $10,300 Subtotal Labor and Material $323,980 Design and Construction Management (16%of L&M)$51,837 Contingency (15%of L&M)$48,597 Total Estimated Constructed Cost $424,414 HLY 23-426 (10/26/96)120402-01/rh 38 APPENDIX A HLY 23-426 (10/26/96)120402-01/rh 39 UNALASKA GEOTHERMAL STUDY TRIP REPORT OF RON BEAZER,POWER ENGINEERS,INC. AUGUST 12 THROUGH 16,1996 I traveled to Dutch Harbor on Monday,August 12,1996 to meet with City Staff and Power Plant Managers/Operators for Unisea Seafood,Alyeska Seafood,and Westward Seafood. CITY OF UNALASKA INTERVIEWS I met with City of Unalaska's City Manager Mark Ernest at 10:00 AM Tuesday and gave him an overview of POWER's scope of work for the continuation of the project.The items that we discussed were: e Overview of Project:The past studies looked at a Makushin Power Plant output of about 7 megawatts (MW),which was assumed to be mainly sold to the City.The R.W.Beck study from 1995 looked at the comparative costs of different power alternatives with plant output up to approximately 1ISMW.According to the Beck study,for the project to be economically feasible,the Makushin output would need to be connected to the City grid and sold to the industrial customers. e POWER Engineers,Inc (POWER)is contracted by Exergy to look at the feasibility and costs to interconnect each of the three major seafood plants to the grid.To perform this task,POWER will be looking into the following areas; 1.Physical interconnects will be considered for feasibility and cost for the City Grid, Unisea Seafood,Alyeska Seafood,and Westward Seafood. 2.Operation of the grid will be evaluated for the following areas;Load Sharing, Reactive Power Generation,Economic Unit Commitment,Spinning Reserve and Responsibility for Operation/Dispatch. After the short update to Mark Ernest,I visited with Mike Golat and Brian Amber of the City's electrical department.We discussed the above issues and the following information. e The City has budgeted approximately $500,000 to perform upgrade work in the diesel plant.Almost the entire transmission and distribution systems are now underground cable with loop feeds through the 34.5kV system. e The 34.5kV system is also nearly complete to the Alyeska Seafood facility,and the conduit is in and 'daylighted'to near the end of Broadway near the plant. HLY 23-333 (8/27/96)1 Approximately 1,000 feet of 34.5kV cable will be required to complete the installation. The 34.5kV system is primarily 4/0 copper 15kV 220mil cable with a full concentric sheathed neutral.The City only uses Elastimold elbows and splices at this time. Voltage regulation of the system is provided by the generators.The City has applied for PSD permits and is expecting resolution soon. e The connection to Unisea is complete (34.5kV cable presently energized at 12.47kV) with a 1500kVA transformer capacity at this time.There is a SOOOkVA transformer available at the site,but it is not connected at this time. e Westward Seafood is connected on the 12.47kV system with one 75kVA and one 750kVA power transformers at this time.The cable to Westward is presently 1/0 copper 15kV underground cable. e The City currently operates one generator remote from the Power Plant.This unit is located near the City's shops and is normally base-loaded.There have been times that an outage on the 34.5kV system has resulted in this unit remaining on-line providing power to the isolated portion of the City system on Unalaska. e One interconnect point to the City grid would be at the Margaret Bay Substation 34.5kV four-way switch.Another possibility would be to connect directly into the Town Substation 34.5kV bus through a breaker. After the interview with Mike Golat and Brian Amber,I met with Roger Deffendall for a tour of the system.We visited the Town Substation,Margaret Bay Substation,Unisea Power Plant interconnect,City Power Plant and the undersea cable crossing.There is room on the third floor of the City Power Plant for a dispatch center if one is desirable. The walls and floors are four foot thick reinforced concrete.The electrical department is currently refurbishing the interior of this building for use as a storage facility.This building is located near the crest of the hill,which would facilitate communication by radio or microwave.The City Power House is currently using Allen-Bradley PLC's for control and data acquisition.Roger indicated that some work will need to be accomplished to raise the exhaust stacks on the diesel units to meet the air quality requirements. Due to the high winds in the area,the City would not be particularly interested in connecting their underground system to the Makushin line if it has significant portions of overhead construction.The previous cost estimates were based on some line sections being 34.5kV overhead construction.The City has spent considerable time and capital to get their system underground.Now that it is underground and the Town Substation has been replaced with modern metal enclosed switchgear,the system reliability has improved. They do not want to degrade the improved reliability. HLY 23-333 (8/27/96)2 UNISEA SEAFOOD INTERVIEW I met with John Brown of Unisea in the afternoon.The Unisea plant has a peak load of about 7.4MVA over about a seven-month period,then it drops down to about 2.0MW for the duration of the off-season.The generation capacity is about 14MW.Some of the exhaust stack heat is used to produce hot water for heating the hotel and other buildings. The present interconnect to the City of Unalaska grid is at 12.47kV and is limited to 1SO00kVA.The power flow at this time is always to the City.If the City requires additional power,they call Unisea and arrange to take a specified increment of power. Unisea operators then adjust the fields of their generators to output the additional power. If the interconnect point was increased in capacity,the transformer would remain in the same place.There is sufficient capacity on the low voltage side for the grid to supply full Unisea power requirements (2000A breaker and bus)though the existing connection. There may need to be some 5kV cable added from the transformer to the switchgear,but there is sufficient room in the conduit and cable raceways.The interconnect is a manual transfer at this time.If the grid can be shown to be reliable and the power costs economical,Unisea would probably commit to taking their baseload from the grid and following load with their generators based on need.Drawings for the interconnect should be available from Western Power Engineering. John believes that it costs Unisea approximately $1,000 per minute for a power outage during peak processing periods,and the loss begins immediately.His experience with the interconnect is that they may have had two outages in the last year related to the City's grid being faulted and taking the Unisea generators down with the grid.John's main concern is that there will need to be additional automatic sectionalizing of the City's 34.5kV grid to reduce the exposure of the plants to system faults. Unisea will get their air quality permits approved as of September.They are allowed three generators operating at full capacity 24 hour per day and one unit operating for four hours per day.They are being required to burn low sulfur fuels which adds to the fuel cost. A dispatch center could be located at the Unisea plant,but there would need to be some significant modification to provide room for a Mimic Board along with the CRT's, computer processors and communications gear. ALYESKA SEAFOOD INTERVIEW I met with Steve Tate on Wednesday morning.Alyeska's peak load is about 3.5MW with a minimum of 800kW.They have 5.6MW of generation installed,and they also recover some of the waste heat for other in-plant uses.Dealing with the EPA regulations is resulting in lower efficiencies for their diesel generation. HLY 23-333 (8/27/96)3 Alyeska does not presently have an interconnect with the City.They do have existing 4.16kV,2000A breaker cubicles which are fully equipped for an additional generator which could easily be used for an interconnect.If they were to have an interconnect,the transformer would need to be located near the rear of the powerhouse with cable in trays to the breaker cubicle. Mr.Tate indicated that prior to committing to any long-term or peak load power contract, Alyeska would want to assess the reliability of the City grid by perhaps taking the 800kW of house load for a time sufficient to determine the grid reliability.At this time,the house load is not easily broken out from the processing load.If the power was determined to economical and reliable,they would certainly consider additional use in the future. When they have an outage,the fish in the freezers are downgraded one grade,which results in a loss of approximately $3,000.Steve indicates that they usually experience about two outages per year. WESTWARD SEAFOOD INTERVIEW I also met with Marcus Alden on Wednesday moming.Westward's peak load is approximately 4.5MW with a low of 1.0MW.The off peak lasts about four to six months. They have 6.6MW of generation capacity installed and use waste heat from the exhausts to provide building heat. The present interconnect is one 75kVA and one 750kVA transformer at 12.47kV.The only time that Westward connects to the City grid is to black-start their power plant.The interconnect switchgear is a 4.16kV,2000A breaker equipped with synch panels and relaying.They would only be interested in the interconnect after it was shown to be reliable and economical. Plant outages cost $100,000 to $150,000 per hour.Westward has only experienced one outage in the last two years,which lasted approximately one hour. HLY 23-333 (8/27/96)4 APPENDIX B HLY 23-426 (10/26/96)120402-01/rh 40