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HomeMy WebLinkAboutWind Energy Study 4-2009 AEA Oct 09Engineering, Inc. 2522 Arctic Boulevard, Suite 200 Anchorage, AK 99503-2516 P (907) 276-0521 F (907)-2764751 ASSOCIATION of VILLAGE COUNCIL PRESIDENTS REGIONAL HOUSING AUTHORITY (AVCP RHA) CAMPUS WIND ENERGY STUDY April 14, 2009 Prepared by Xuan P. Ta, P.E. 191 E. Swanson Avenue, Suite 101 Wasilla, AK 99654 P (907) 357-1521 F (907)357-1751 AVCP RHA Campus - Wind Energy Study Bethel, Alaska Table of Contents ALASKA'S RENEWABLE ENERGY EXECUTIVE SUMMARY SITE DESCRIPTION 1'��II�f77 • • LOAD STUDY OFF -GRID SYSTEM GRID -CONNECTED SYSTEM CONCLUSIONS AND RECOMMENDATIONS PROJECT COST ESTIMATE APPENDIX A —System Cash Flow APPENDIX B —Historical Demand Load Data APPENDIX C —Recommended Practices GLOSSARY AVCP RHA Campus - Wind Energy Study Bethel, Alaska Alaska's Renewable Energy Resources The major renewable energy resources consist of wind, solar, biomass, geothermal, hydro, and ocean power resources play an important role in the future of our nation. Wind Resource: Wind energy converts kinetic energy that is present in the wind into more useful forms of energy such as mechanical energy or electricity. Large modern wind turbines operate together in wind farms to produce electricity for utilities. Small turbines are used by homeowners and remote villages to help meet energy needs. According to Alaska Energy Authority Wind Resource Assessment for Bethel, Alaska dated February 2008, a seven level classification system based on wind power density (WPD) is used to simplify the comparison of potential wind sites. Areas of Class 4 and higher are considered suitable to utility -scale wind power as follows: Classes of Wind Power Densit Wind Power Class Resource Potential WPD (W/m2) @30 m Wind Speed (m/s) @ 30 m WPD (W/m2) @50 m Wind Speed (m/s) @ 30 m 1 Poor <160 <5.1 <200 <5.6 2 Marginal 160 - 240 5A — 5.8 200 - 300 5.6 — 6.5 3 Fair 240 — 320 5.8 — 6.5 300 — 400 6.4 — 7.0 4 Good 320 — 400 6.5 — TO 400 — 500 7.0— 7.5 5 Excellent 400 - 480 7.0 — 7.4 500 - 680 7.5— 8.0 6 Outstanding 480 — 640 7A — 8.2 600 — 800 8,0.8.8 7 Superb > 640 > 8.2 > 800 > 8.8 A class 4 wind resource is available in Bethel area. Solar Resource: Solar energy from the sun travels to the earth in the form of electromagnetic radiation similar to radio waves, but in a different frequency range. Available solar energy is often expressed in units of energy per time per unit area, such as watt-hours per square meter (Wh/m2). The available solar energy is primarily dependent upon how high the sun is in the sky and current cloud conditions. On a monthly or annual basis, the amount of solar energy available also depends upon the location. According to Renewable Energy Atlas of Alaska dated July 2007, Alaska annual average solar Insolation is follows: Solar —Annual Average Solar Insolation kWh/m2/day December Average Insolation <3.5 June Average Insolation 3.5 — 4.0 Biomass Resource: The term "biomass" means any plant derived organic matter available on a renewable basis, including dedicated energy corps and trees, agricultural food and feed crops, agricultural crop wastes and residues, wood wastes and residues, aquatic plants, animal wastes, municipal wastes, and other waste materials. Bioenergy is produced by the release of stored chemical energy contained in fuels made from biomass. Biomass is actually a product of solar energy that has been stored by the RSA Engineering, Inc. Page 3 AVCP RHA Campus - Wind Energy Study Bethel, Alaska photosynthetic activity of plants. The plants remove CO2 from the atmosphere and combine it with water to produce biomass. According to Renewable Energy Atlas of Alaska dated July 20073 the State of Alaska's primary biomass fuels are wood; sawmill wastes, fish byproducts, and municipal waste. Wood remains an important renewable energy source for Alaskans for space heating statewide. Ground fish processors are in Unalaska, Kodiak and other locations produce fish oil for power production each year. Geothermal Resource: Geothermal energy is the heat from the Earth. It is clean and sustainable. Resources of geothermal energy range from the shallow ground to hot water and hot rock found a few miles beneath the Earth's surface, and down even deeper to the extremely high temperature of molten rock called magma According to Renewable Energy Atlas of Alaska dated July 2007, the State of Alaska has four distinct geothermal resource regions. The first distinct geothermal resource region is the interior Hot Springs, which include the band of hot springs that run east - west from the Yukon Territory of Canada to the Seward Peninsula. The second distinct geothermal resource region is the Southeast Hot Springs. The third distinct geothermal resource region is the Wrangell Mountains, and the fourth distinct geothermal resource region is the Ring of Fire Volcanoes, which includes the Aleutians, the Alaska Peninsula, and Baranof Island. Bethel area is not located in the above geothermal resource regions; therefore, geothermal resource is not available in Bethel. Hydroelectric Resource: Hydroelectric energy is a renewable energy source dependent upon the hydrologic cycle of water, which involves evaporation, precipitation and the flow A water due to gravity. According to Renewable Energy Atlas of Alaska dated July 2007, most of the state's developed hydro resources are located near communities in South-central, the Alaska Peninsula, and Southeast — mountainous regions with moderate to high precipitation. However, many rural communities located on the Yukon and other large rivers are interested in using river current for generating power. Ocean Resource: According to Renewable Energy Atlas of Alaska dated July 2007, ocean energy consists of three general categories. The first category is ocean thermal energy conversion. The second category is tidal energy, and the third category is wave energy. The ocean thermal energy conversion applications are not suitable for development in Alaska. Tidal energy is produced through the use of tidal energy generators. These large underwater turbines are placed in area with high tidal movements, and are designed to capture the kinetic motion of the ebbing and surging of ocean tides in order to produce electricity Waves are caused by the wind blowing over the surface of the ocean. In many areas of the world, the wind blows with enough consistency and force to provide continuous waves. There is tremendous energy in the ocean waves. Wave power devices extract AVCP RHA Campus - Wind Energy Study Bethel, Alaska energy directly from the surface motion of ocean waves or from pressure fluctuations below the surface. The technology for exploiting tidal and wave energy potentials are not yet commercially available. Executive Summary The purpose of this report is to provide a report covering the studying the possibility of power generation using wind energy for the Association of Village Council Presidents Regional Housing Authority (AVCP RHA) complex. Wind energy is a pollution -free, infinitely sustainable form of energy. It does not use fuel; it does not produce greenhouse gasses, and it does not produce toxic or radioactive waste. The AVCP RHA complex consists of eleven existing and one new building as followings: ❖ AVCP RHA Office Building ❖ Development Office Building ❖ Lulu Heron Building ❖ Building A (Units range from #1 through #4) ❖ Building B (Units range from #17 through #20) ❖ Building C (Units range from #5 through #10) ❖ Building D (Units range from #11 through #16) ❖ Building E (Units range from #21 through #32 ❖ Warehouse #1 ❖ Warehouse #2 ❖ New AVCP RHA Office Expansion Building A total calculated demand load for the AVCP RHA complex is 581,573 kWh/year. Alaska Energy Authority (AEA) had conducted the Wind Resource Assessment for Bethel, Alaska. The measured wind speed data indicate a Class 4 wind resource in Bethel area, providing a good potential for wind power development. The wind turbine models currently available for a remote Alaska installation are very limited. Due to the risks associated with the harsh operating conditions, remote location, and lack of service personnel, few manufacturers are willing to support the Alaska market. Alaska Village Electric Cooperative (AVEC) and Kotzebue Electric Association (KEA) utilities have installed Northern Power System Model NW100 wind diesel turbines in Kotzebue, Toksook Bay, and Kasigluk. It is our understanding, Federal regulations (specially, the Public Utility Regulatory Policies Act of 1978, or PURPA) requires utilities to connect with and purchase power from small wind energy systems; therefore, we would recommend AVCP RHA Representative continue their efforts to persuade Bethel Utilities Corporation (BUC) to support any wind power project to be undertaken by the city or private sector or any other person because grid -connected small wind turbines can provide many benefits to utilities as well as wind turbine owners. In rural areas with long power lines, they can improve power quality (by boosting voltage) and reduce line losses. They can also provide extra generating capacity and reduce power plant emission. AVCP RHA Campus - Wind Energy Study Bethel, Alaska We recommend a minimum of 2-Northerwind 100/21 wind turbines, power conditioning inverter, net metering, step-down transformer, and disconnect switch to connect to the BUC grid. Site Description Bethel is located at the mouth of the Kuskokwim River, 40 miles (74.37 km) inland from the Bering Sea and 400 air miles west of Anchorage. The community is located at approximately 600 47' 8" North Latitude and 1610 53' 6" West Longitude. According to the United State Census Bureau, the community has a total area of 50 square miles (126 square km), of which, 44 square miles (113 square km) of it is land and 5 square miles (13 square km) of it is water. The total area is 10% water. Though the region is flat and generally treeless, Bethel lies inside the Yukon Delta National Wildlife Refuge, the largest wildlife refuge in the United States. Precipitation average 16 inches (40.64 cm) a year in this area and snowfall averages 50 inches (127 cm) per year. Summer temperatures range from 420F (5.56°C) to 620F (16.670C). Winter temperatures range from -2°F (-18.89°C) to -19°F (-28.330C). (Community profile information from State of Alaska Department of Commerce, Community and Economic Development website http://www. commerce,state. ak. us/dca/com mdb/C I S.cfm) Wind Resource In December 2004, Alaska Energy Authority (AEA) installed a 50-meter meteorological tower on the high ground west of the Bethel airport. The resulting data set represents the long-term wind resource at the site. RSA Engineering, Inc. Page 6 AVCP RHA Campus - Wind Energy Study Bethel, Alaska t- _ii:: ti:.L.G_ S� ethel I - ILA i ,. s - J �� WE: ' - IN - Topographic Map of Met Tower Site and Surrounding Area (Topographic Map of Met Tower Site and Surrounding Area information from Alaska Energy Authority (AEA) Wind Resource Assessment for Bethel, Alaska) AEA Wind Resource Assessment for Bethel, Alaska dated February 21, 2006, the strong winds come from the northeast, while the lighter summer winds tend to come from the south. An average wind speed is 7.3 m/s at a height of 50 meters above ground level as shown in Table 6 of the AEA Wind Resource Assessment for Bethel, Alaska report. Table 6. Estimated Lon -Term Wind Speeds at Met Tower Site, 50m Hei ht m/s) Hour Jan Feb Mar Apr May Jun Jul AUCI Se Oct Nov Dec A•r O 9.6 8.5 8.8 8.1 6.4 6.0 6.8 6.4 6.8 7.8 8.0I 8.4 7.6 1 9.4 8.5 8.7 8.0 6.3 6.0 6.4 6 2 6.5 7.8 7.9 6.3 7.5 2 9.5 8.4 8.6 8.0 6.0 5.9 5.9 6.0 6.4 7.8 7.7 8.8 7.4 3 9.5 8.2 8.4 8.0 6.0 5.8 5.8 5.9 6.5 7.8 7.8 8.7 7.4 4 9.5 8.5 8.7 7.9 6.0 6.6 5.6 5.8 6.5 7.5 7.8 8.5 7.3 9.3 8.4 8.8 8.1 6.9 5.4 5.3 6.0 6.5 7.4 7.7 8.3 7.3 6 9_-1 8.2 8.7 7.9 6.7 5.0 52 5.8 6.4 7.4 7.9 8.3 7.1 7 9.3 8.0 8.7 7.9 6.2 4.7 4.8 5.6 6.3 7.6 7.9 6.3 7.0 8 9.3 8.2 8.6 7.5 5.0 4.7 4.8 5.6 6.3 7.9 7.9 6.5 7.0 9 9.2 8.5 8.7 7.1 5.1 4.8 5.1 5.8 6.3 7.7 8.1 6.4 7.1 10 9.3 8.1 8.9 6.7 5.6 6.0 5.0 6.1 6.7 7.4 8.3 B.2 7.1 1 1 9.4 8.1 8.8 6.5 5.8 5.2 5.1 6.4 6.9 7.4 8.3 6A 7.2 12 9.3 8.2 8.8 6.7 5.9 5.3 5.3 6..4 6.9 7.6 8.1 8.2 7.2 13 9.3 8.4 8.6 7.0 6.0 5.3 5.2 6.6 7.2 7.4 7.8 6.2 7.3 14 9.3 8.4 8.4 7.1 6.1 5.3 5.3 6.7 7.3 7.5 7.7 8.7 7.3 15 9.6 8.3 8.7 7.3 6.1 5.4 5.7 6.7 7.0 7.6 7.7 8.3 7.4 16 9.6 8.2 8.7 7.3 6.4 5.6 6.0 6.6 7.0 7.3 7.8 6_3 7.4 17 9.7 8.3 8.6 7.6 6.7 5.7 5.8 6.6 6.9 7.3 7.8 8.3 7.4 18 9.5 8.3 8.3 7.7 6.5 6.0 6.0 6.6 6.8 7.5 8.0 6.7 7.5 19 9.5 8.4 8.5 7.9 62 6.0 6.1 6.3 6.7 7.6 8.1 87 7.5 20 9.3 8.1 8.8 8.0 6.3 6.0 5.7 5.9 6.7 7.7 7.9 8.4 7.4 21 9.3 8.0 8.8 8.2 6.6 5.9 5.7 6.1 6.7 7.9 7.9 6.3 7.4 22 9.6 8.01 8.8 8.1 6.6 6.0 6.0 6.4 6.8 8.2 7.9 8.7 7.6 2 3 9.4 82 6.6 6.2 6.4 6.2 6.4 6.3 7.0 8.0 8.1 8.6 7.6 Av 9.4 8.3 8.7 7.6 6.0 6.6 G.6 6.2 6.7 7.6 7.9 8.4 7.3 The meteorological Tower Data Synopsis for Bethel, Alaska is as noted: RSA Engineering, Inc. Page 7 AVCP RHA Campus - Wind Energy Study Bethel, Alaska • Annual Average Wind Speed (30m height): • Average Wind Power Density (30m height): • Annual Average Wind Speed (50m height): • Average Wind Power Density (50m height): • Wind Power Class (range = 1 to 7): • Rating (Poor, Marginal, Fair, Good, Excellent, Outstanding): • Prevailing Wind Direction: • Wind Shear • Turbulence Intensity • Data Start Date • Data End Date 6.7 m/s (15.0 mph) 345 W/m2 7.3 m/s (16.3 mph) 440 W/m2 Class 4 Good Northeast 0.19 (average) 0.06 (low) 12/9/2004 2/12/2006 (The wind resource information from AEA Wind Resource Assessment for Bethel, Alaska website http://www.akenergyauthority,orci/programwind.thmi Load Study 1. The historical demand usage in kWh/year for each building is included in the Appendix C - Historical Demand Load Data'. The annual demand usage in kWh/year for the existing buildings as shown on the attached 'AVCP RHA kWh Demand History'. Summary AVCP RHA kWh historical Demand Load Data 11l19707 12t17i07 1i29108 2+1:1;08 3r19ic8 4i21;4A S119rp8 6:19t08 7t21t08 8,�19I08 �?19r'OS i0<'21108 Remarks Building A 1,800 1:9971 3t2771 2,0561 15613 1;8521 17160 1J261 t299 11323 17?22 1165 See Note 1 Building B 1,107 1.161 1 597 1.368 1,172 1,241 961 1,077 997 1.047 992 1,188 See Note'1 Building C 1,767 177 1,996 1,837 #,520 1,613 1'310 1.701 1 E13 1,714 1,418 1.741 See Note 1 Building D 2,015 2;2461 2J711 2,1561 1 J951 11949 1,393 1 ,3601 1,349 1,168 1 ,3141 1,4141 See Note 1 Buildino E 6,220 5t9021 7,3931 5 465 1 5JR61 6,5811 b,Wbj 5.578 5.331 4 801 1 !>,2321 6.126 1 See Note 1 ota year See Note' Lulu Heron 9,666 9.814 10,%5 9,354 QT1251 9.7681 9.3931 10,570 10,746 gr7871 10,6051 10 772 See Note 1 AVCP RHA Office 8,487 9.416 10.318 9.745 9,363 ft.291 7.772 7.915 8.130 7.667 8.394 8.843 See Note 1 Develo Went Office 2,435 2,589 3,009 2.702 2 543 2 471 2,173 2.161 2.155 1.966 2,183 2.334 See Note 1 Warehouse #1 509 405 563 466 438 433 308 295 300 344 376 335 See Note 1 are ouse# b _ _ee Note o a ma n Tl iti7year ota 2721119 See Note 3 Grant total kWh+year 417,982 See Note 4 Notes: #. See attached historical demand load data for each building. 2. Annual Demand usage of existing buildings -A','B', 'C', 'D', and 'E` . 3. Annual Demand usage of existing buifdings Lu€u Heron, AVCP RHA Offrce, Development Crfiice; Warehouse?; t; and Warehouse #2 4. Annual Demand usage of all AVCP RHA Complex. 2. The calculated demand usage in kWh/year for the new AVCP Office Expansion Building as shown on the attached AVCP RHA Calculated Demand Load Data'. AVCP RHA Campus - Wind Energy Study Bethel, Alaska Rvcri RHn Calcatated kt m aenianss Laad Data for the taew omce Ex anstin euudtn __.I fi`!.`69 _. _2mos vv09 4'evas 5'1-.'<+9 6!vasl 7fIfOB &VID-9 5.t'04 l4'}jDql 1IM09 12/1109 Remars ... s7r U111iCe Expansion 3t1ding 1 13.789 12.536 73.71�'1 13.785 13.163 13.789 14-41513.153 15.789 13.789 13.163 t4.446 Tabt kVdht ear 163,591 Na;:• Ogee £xparsion 8vilding: Rn apprarimatety gross area for the nar` olfiae bvkEMg s: The folb°,vmg assumptions are made to determine the calculated demand toad: Lighting Load 3Z VA?SF= 56.00.7 VA Ta1al calculated demand bad in k'vY 910.50 po.:ar?actA^ 539.23 k4'1 Tha fotia'r.1ng issuntpNins are made 10 compute iha demand usage far each €ninth: Office operatbn 10 hrrday and 5 deystweek Load Factor (LF) Vanes 35 to 50 % tied Factor ((k`vVnfnOL't8 ih Pe?'od)rk1Nj Thus,.the k4L'im per manth� #Wh = [t-F"(k5N"(hrlday # at days)martih}j i:;'1h �: tF°R'v's`°hr# 0.35` 13?.23j`19hrsday°(.46daystmanln}.= - 04S'(13�24)'1Onrtda'r'2sda}�meath)= = t}46'i33?.^_ € filiti"dap'�Ciais-nroset}r{= = 04.(t�.S9}'IOhrrriap'(23daaaimanlfll= An astimaiad fatal kWh)yi'tar a new Ode Expansion Bitlidirrg is: ta.ao- 6$F (2@08 MEC Table 220.127 (2006 NEC 220,f4(KX2`,j jAasume 4.0 VkSFj [Assume 0.75 :rASSF) [A load "are the maximum current is oxpectod to con nue for 3 hrc or rnoroj (2005 NEC 230A2+Aj{ 1}j [Aastmme VA 04 mechanical load is a continuous loa (Assume a ICHF AHU] [Lead taaor iexpressad In parcantag€} is m mamaura od the w?omlmty mrsd efftiency t:1ih s�mich eteetocal energy is 3:eeng used,j 7P-..in%i 6�a I€or Fe.vra.77 13,163ktrJ71 (firP.xay:+�9ustNi.emGerj 13.7S9 1.1`;h iEor Jarauasy M xch: Apri;' June. Sep!emset, Ocla s rj 1:.416 k`lfim Tor dol3=i�c+l:rsbPr? 1G3,63t1 klYhtyt Based on the above calculation, the total annual kWh for both existing and new buildings is 581,573 kWh. The best measure of wind turbine performance is annual energy output. The difference between power and energy is that power (kilowatts [kW]) is the rate at which electricity is consumed. An estimate of the annual energy output from the wind turbine, kWh/year, is the best way to determine whether a particular wind turbine and tower will produce enough electricity to meet your needs. To get a preliminary estimate of the performance of a particular wind turbine, use the formula below: AEO = 0.01328*D2*V3 Where: AEO =Annual Energy Output, kWh/year; D =Rotor diameter, feet V =Annual average wind speed, mph However, we recommend coordinating with the specific wind turbine manufacturer for their assistance on sizing, determining the quantity, and sitting of wind turbines, which will be needed to provide power for the AVCP RHA Campus. A wind turbine manufacturer can also help you estimate the energy production and the expected payback period based on the particular wind turbine power curve, the average annual wind speed at your site, the height of the tower you plan to use, and the wind frequency distribution — that is the number of hours the wind blows at each speed during an average year. The calculation will be adjusted for your elevation, which affects air density and thus turbine power output. Our report is based on Northwind 100/21: 100 kW, 3-phase, 4-wire 480VAC rated power output, 21 meter rotor (69 ft), variable speed stall -controlled, 37-meter hub height. Additional information is available at http://www. northerpower. comm/. AVCP RHA Campus - Wind Energy Study Bethel, Alaska 100 so Y 60 u 40 V N w 10 Q 0 5 10 15 10 15 Wind Sneed at HUb Heiilht ira:;i The annual energy calculation for the Northwind 100/21 is shown on the attached Northwind 100/21 — Annual Energy Calculation'. Based on the calculation, one Northwind 100/21 will produce an estimate of 291,243 kWhNr; therefore a minimum of two Northwind 100/21 turbines will be required to supply power to the AVCP RHA Campus: 291,243 kWh x 2 = 582,486 kWh RSA Engineering, Inc. Page 10 AVCP RHA Campus - Wind Energy Study Bethel, Alaska Annual Energy Calculation Turbine Model: 4>r:1041 DOrneteF 21 Site: Ietr�i, AK Density: 1225 kg W3 Vref T3 nTs Href be m \Mnd Shear 0.12 - Hub Height 37 m Vhub 5,9 rr's Form Factor. k 200 - Scale Factor; A 7.80 - Availability_ 1009E Net Losses: 03E. Timeon-line 873C Ho,s 'Yr -n4ruv 291,243 kWHrs!Yr Wind Speed Distribution Vhub HoursNr Mps 1 252.1 537 2 3 7424 4 8E2.7 951.1 c g04.1 7 sg97 8 8042 9 5c4.8 10 557A 11 434.7 12 325.3 13 234.0 14 181.9 5 107.9 id 59.3 17 42.9 18 25.0 19 14.7 20 82 21 4.4 22 2.3 G.5 2E 0.3 P9•aer Curve Vhub Power m s Me 15 2 -D.5 3 0j 4 3.7 10.5 e 19.0 7 2CA 41.0 9 54.3 10 55.8 11 77.7 12 MA 13 92.8 14 97.3 15 100.0 15 }00.E 17 1flG G tc 19 99.4 20 9E.5 21 F7.8 22 97.3 23 S7.3 24 gc.0 25 Pxz7 Proposed Wind Farm Location Energy Pr9dt&C219n Vhub Run Tt Energy Hours/Yr kWhrstYr 1 2i2.1 -141 2 537.2 3 742 c 523 4 8E2.7 320 9521 9U50 5 954.1 18141 7 899.7 2E449 E 804.2 22952 9 5154.E 372G2 10 557_4 37213 : 434.7 23775 325.3 2600 43 224.0 217f3 14 1e1.9 17°51 107.9 10ie4 15 ce 3 89a0 }7 42.0 4311 28 25.e, 2554 19 14.7 1453 2G E2 E07 4.4 422 221 e tit; 24 0.5 E4 2 0.3 1 25 Annual Energy Prnduc4on Yref Annual Output Annual Output mWS kWh MWh d.O 10,092 197.1 6.5 233,820 223.8 7.G 2590e4 2d9:9 7.5 305,251 305.3 8.0 3399259 33c.3 2.5 371,548 371.5 We can have varied wind resources within the same property. In addition to measuring or finding out about the annual wind speeds, we need to know about the prevailing directions of the wind at our site. If we locate the wind turbine on the top of or on the windy side of a hill, we will have more access to prevailing winds than in a gully or on the AVCP RHA Campus - Wind Energy Study Bethel, Alaska leeward (sheltered) side of a hill on the same property. In addition to geologic formations, we need to consider existing obstacles such as trees, buildings, and sheds, and we need to plan for future obstruction such as new building that have not reached their full height. The wind turbine needs to be sited upwind of buildings and trees, and a general rule of thumb for proper and efficient operation of a wind turbine is that the bottom of the turbine's blades should be 30 feet above the top of anything within 300 feet. We also need enough room to raise and lower the tower for maintenance, and if the tower is guyed, room shall be allowed for guy wires. The farther we place the wind turbine form obstacles such as building or trees, the less turbulence we will encounter. See Fig. 1 below for illustration, obstruction of the Wind by o wilding or Tree of Height (H) Figure 1: Height or Distance Needed (Obstruction of the Wind by a Building or Tree of Height (H) information from U.S. Department of Energy —Small Wind Electric System A U.S. Consumer's Guide) The best place to site these wind turbines is going to be on a parcel of land south of the Lulu Heron Building. This land has not yet been purchased. We recommend that the wind turbines are to be sited at least 50 m (or 165 ft) away from the commercial office buildings and between 85 to 125 m (280 to 410 ft) apart at the base. The arrangement is advisory only. It is based on limited information about the land and wind rose. It is the responsible of the Owner (or purchaser) to comply with all local, provincial and federal regulations. If a row is to be added the second row needs to be a minimum of 7 rotor blade diameters apart. Northwind 100/21 i.e. rotor diameter is 21 meter the rows need to be 147 meter apart or 482 feet apart. We suggest the Owner research the potential obstacles before investing in a wind energy system as follows: ➢ Zoning Issues: A wind turbine is a tall structure that requires a building permit. Zoning regulations often limit the height, Most cities and towns have ordinances AVCP RHA Campus - Wind Energy Study Bethel, Alaska to ensure that structures and activities are safe, proper and compatible with existing or planned development. Many jurisdictions restrict the height of structure permitted in residentially zone areas, although variances are often obtainable. A conditional use permit may be required, which could specify a number of requirements the installation must meet. ➢ Environment Issues: Your neighbors might object to a wind turbine that blocks their view, or they might be concerned about noise. The Owner should consider obstacles that might block the wind (or create turbulence) in the future, such as planned construction or immature trees. ➢ Tower Height: Country ordinances that may restrict tower height may adversely affect optimum economics for small wind turbine. Unless the zoning jurisdiction has established small wind turbine as a "permitted" or "conditional" use, it may be necessary to obtain a variance or special use permit to erect an adequate power. ➢ Compliance with The Federal Aviation Administration (FAA): The FAA has regulations on the height of structures, particularly those near the approach path to runways at local airports. Objects that are higher than 200 feet (61 meters) above ground level must be reported, and beacon lights may be required. If you are within 10 miles of an airport, no matter how tall your tower will be, you should contact your local FAA office to determine if you need to file for permission to erect a tower. ➢ Utility Notification: The Owner should contact Bethel Utilities Corporation (BUC) and reach an agreement with BUC before connecting to their distribution lines to address any power quality and safety concerns. ➢ Compliance with National Electrical Code and National Electrical Safety Code: Electrical code requirements emphasize proper wiring and installation and the use of components that have been certified for fire and electrical safety, such as Underwriters Laboratories (UL). The utility's principal concern will be that your wind turbine automatically stops delivering any electricity to power lines during an outage. Otherwise line workers and the public, thinking that the line is "dead", might not take normal precautions and might be injured. Another concern among the utilities is that the power from your wind turbine system synchronizes properly with the utility's grid, and that is match the utility's own power in term of voltage, frequency, and power quality. A list of practices recommended by the "Permitting Small Wind Turbines: Handbook" are included in Appendix D —Recommended Practices. Off -Grid System An off -grid system (stand-alone system which is not connected to the utility grid) requires batteries to store excess power generated for use when the wind is calm. They also need a charge controller to keep the batteries from overcharging, inverter to convert DC to AC power, and back-up power source for complete energy independence. Small wind diesel hybrid system that combines a wind system with a photovoltaic (PV) and/or diesel generator can provide reliable off -grid power around the clock for communities or facilities. For the times when neither the wind turbine nor the PV modules are producing, most hybrid systems provide power through batteries and/or an engine -generator powered by conventional fuels such as diesel. If the batteries run low, the engine -generator can provide power and recharge the batteries. Adding an engine - generator makes the system more complex, but modern electronic controllers can RSA Engineering, Inc. Page 13 AVCP RHA Campus - Wind Energy Study Bethel, Alaska operate these systems automatically. An engine -generator can also reduce the size of the other components needed for the system. The storage capacity must be large enough to supply electrical needs during non -charging periods. The battery banks are typically sized to supply the electrical load for one to three days. An off -grid hybrid system may be practical if the following conditions exist: • Bethel area with average annual wind speed of at least 9 mph (4.0 m/s). • A grid connection is not available or can only be made through an expensive extension. • You would like to gain energy independence from the utility. • You would like to generate clean power. Advantages: • Wind energy is free — It needs no fuel and produces no waste or pollution. • Solar energy is free — It needs no fuel and produces no waste or pollution. Disadvantages: • Solar energy can be unreliable unless you are in very sunny climate. The amount of sunlight that arrives at the earth's surface is not constant. It depends on location, time of day, time of year, and weather conditions. • Because the sun does not deliver that much energy to any one place at any one time, a large surface area is required to collect the energy at a useful rate. • Very expensive to build solar power stations. Solar cells cost a great deal compared to the amount of electricity they will produce in their life time. • Very expensive to build the battery banks to store energy. The battery banks are typically sized to supply the electrical load for one to cater for periods with little wind or sun. • High maintenance cost. • Cost of diesel fuel for operating the generator. We recommend utilizing diesel -fired generator (prime rated) instead of solar energy in an Off -Grid Connection System. The generator will be the primary source of energy. Its use will be minimized by using wind resource. The Off -Grid Connection System is the most expensive and the most complicated system. This would require AVCP RHA to run a power plant and distribution grid. Wind turbines would be connected to the diesel generator power grid as mentioned in Grid - Connected System Option 3, a secondary load controller would be included to maintain frequency and divert excess power from the wind turbines into thermal dump load. Grid -connected System Grid -connected system requires a power conditioning unit (inverter) that makes the turbine output electrically compatible with the utility grid. Usually, batteries are not needed. Small wind energy turbines can be connected to the utility grid which will require the approval of the utility. A grid -connected wind turbine can reduce your consumption of utility -supplied electricity for lighting, appliances, and heating equipment. If the turbine cannot deliver the amount of energy you need, the utility makes up the difference. When the wind system produces more electricity than the facilities require, RSA Engineering, Inc. Page 14 AVCP RHA Campus - Wind Energy Study Bethel, Alaska the excess is sent or sold to the utility. Grid -connected systems can be practical if the following conditions exist: • Bethel area with average annual wind speed of at least 10 mph (4.5 m/s). • Utility -supplied electricity is expensive in Bethel area. • The utility's requirements for connecting your system to its grid are not prohibitively expensive. • There are good incentives for the sale of excess electricity or for the purchase of wind turbines. Advantages: • Wind energy is free — It needs no fuel and produces no waste or pollution. • Battery banks, charge controller, and inverter are not needed. • Backup power is not required. • A grid -connected system has a stable grid to work with where an off -grid system can be less stable. • A grid -connected wind turbine can reduce your consumption of utility -supplied electricity for lighting, heating, appliances, etc. • If the wind turbine cannot deliver the amount of energy you need, the utility makes up the difference. • When the wind system produces more electricity than the household requires, the excess is sent or sold to the utility. • Less operation and maintenance cost. Disadvantages: • Power conditioning unit (inverter) is required for most wind turbines. There are three common wind turbine configuration options for a grid connected system as noted: ❖ Option 1 —Grid Connected without Net Metering: This is the least cost effective system. The Option 1 system consists of two 480V, three-phase wind turbines that are connected to the utility grid. No net metering would be in place; therefore, any excess electricity produced would be fed back into the utility grid with no pay back for the customer. Due to the voltage and phase of the wind turbine, a new power equipment building will be required for housing electrical switchboards and step-down dry type transformers to provide power to 120/240V single-phase and 120/208V three-phase AVCP RHA Campus loads. ❖ Option 2 — Grid Connected with Net Metering. This is the simplest system because it does not require any work on the current AVCP RHA Campus distribution system. The wind turbines could be connected directly to the utility grid and the utility would have to pay for the power that wind turbines produced. The concept of net metering programs is to allow the electricity meters of customers with generating facilities to turn backwards when their wind turbines are producing more energy than the customer's demand. Net metering allows customer to use their generation to offset their consumption over the entire billing period, not just instantaneously. However, net metering varies by state and by utility company, depending on whether net metering was RSA Engineering, Inc. Page 1S AVCP RHA Campus - Wind Energy Study Bethel, Alaska legislated or directed by the Public Utility Commission. Net metering programs all specify a way to handle the net excess generation (NEG) in terms of payment for electricity and/or length of time allowed for NEG credit. Option 3 — Grid Connected with Secondary Load Control: As mentioned in Option 1, the AVCP RHA Campus power system would need to be reconfigured so that all existing and new building loads would be fed from the new power equipment building. An additional secondary load controller would be installed to divert any excess electricity from the wind turbines to a dump load (most likely a boiler or other heating load). All power generated by the wind turbines would be utilized within the AVCP RHA Campus in the form of electricity or heat. Conclusions and Recommendations The wind speed measurements in Bethel indicate a Class 4 wind resource offering a good potential for a wind power system. The viability utilizing this wind resource depends on a number of factors including the installed cost of the wind project and the operation and maintenance costs of the system. The Off -Grid System is more expensive, and less stable than the Grid -Connected System. We recommend to installing a grid -connected system. It is our understanding, Federal regulations (specially, the Public Utility Regulatory Policies Act of 1978, or PURPA) requires utilities to connect with and purchase power from small wind energy systems; therefore, we would recommend AVCP RHA Representative continuing to persuade Bethel Utilities Corporation (BUC) to support any wind power project to be undertaken by the city or private sector or any other person because grid -connected small wind turbines can provide many benefits to utilities as well as wind turbine owners. In rural areas with long power lines, they can improve power quality (by boosting voltage) and reduce line losses. They can also provide extra generating capacity, reduce power plant emission, and reduce the power plant's fuel usage as well. Most utilities can provide a list of requirements for connecting your system to their grids. If the Owner prefers the Off -Grid System we would like to point out the following items that will be required: ➢ The NW 100 wind turbine is a 480V three-phase, four -wire system. Step-down transformers and distribution panels will be required to accommodate 120/240V single-phase, three -wire and 120/208V, three-phase, four -wire existing AVCP RHA Campus loads. ➢ The existing AVCP RHA Campus power distribution system will be reconfigured. ➢ Two generators are recommended to provide power when wind power is insufficient. If the batteries run low, the engine -generator will start to provide power and recharge the batteries. ➢ A power plant will be needed to house electrical and mechanical equipment. The power plant will consist of generator, battery, electrical, and mechanical rooms. ➢ Electrical equipment consists of batteries, chargers, inverter, automatic transfer switch, electronic load controller, etc. AVCP RHA Campus - Wind Energy Study Bethel, Alaska Appendix A —System Cash Flow Installation costs vary greatly depending on local zoning, permitting, and utility connection costs. An estimate of $1,700,000 to provide a small wind power project for the AVCP RHA complex as shown on the enclosed system report from the Homer model, it appears two NW 100 wind turbines will pay for themselves in about five years. AVCP NIIHFk mmLd eGxuF.rlurrt w+umvty As+x�mpitons STEA23 net kt)RiR y.M-w�.36yPatd SG.09 Cemricwrci?ECF'�np kite A 0%. HePu'.isa ka4 k !n�ulud prwec; ;r,U`;sr.! 5 t.7GYr,lIIY� ':nitiu Rats: 4 4d`. Anrcsz= G ;dsmm ::o*.inp: 4m'sx�t 1 533'_;i15-85 c �3551i 1'3.Ta :, y(3'.S4.actf F?3fi 9x35G fi fi'S <i5 Stl:fi°A F.iLih 5S.1 S3o2,E+°i.15 5 11Se SUM 5 tOZC44) 537,413.08 3 1,424.70 V.815 5 1?7 231p 78i[,7ts IiiIn- k 111,11.s SScg2ri.3E 3 2=5A88 1# M% & 525355 7 6 `wt 1 5i1zs5 S '-' 3G71 D WL51542 5 3.OSi6.17 tet_IIG'. 5 1�i.i-N 5 53S?, It'7:Ii S ASV. TZ7 2G1z.Se't: S e.350,7.i 1G $iTf,f;=•i.9: 5?uZY 175 1?t; 950A S. 11 5.1n,015.0 S 2r,c�.1761; 5 U24,92n 12 551fS 4" m S ti l.�.s 24 fifi% 3:9.9 G31 13 9fia7AN,* 4 5576.617 329,14L% S 3470.617 14 5558093,55 5<"37,'_0? 3u1A2?.; a,137,2k1 tc 5i'Fl vg09 5 f..1 29 i 395.19% 5 §01E 91 15 5i73 :0.44 8 7,32":5.42 4?0,74% S `..E:2,SS_' i7 'R' 8.42k5i s 7,4?3,96$ 5770: £ U50,r-. 1a V&I9StT 33 p 8,&.A M4 M{a,I FA4 14 §IU2i7 i:.r,.I"s5: i.„2e. 7;xWA. 2m el S V,sb;; 1e7 mf e1"c 5$? 41, 1ir1 Appendix B -Historical Demand Load Data The historical demand load data for existing buildings are presented in the attached tables as follows: AVCP RHA kWh Demand Histery -Building A 11119t07 12t17t07 1f21lOB 2119708 3f19148 4t21108 5/19108 6719t08 7f2V08 8119t08 9i18106 10M0108 Remarks Atari i?S a5S 1,157 1,752 t.GZ1 855 F40 557 dfi] 524 698 654 a54 Apan iF2 389 390 B55 493 352 379 287 376 370 270 270 142 APan#3 1 2171 2071 49871 1751 2011 2451 1901 2461 2461 330 2:+1 305 .4Part#4 1 2281 2431 ii62 3771 2D51 2B8 1 126 371 591 35l 21 18 Otal Mhlmonth , ' ' ' , 1*165 See Note 3 we, kWhimonth 450 499 .819 514 403 40 290 282 325 331 306 291 Tota.€ kWhtyear 19890 Notes: 1. Minimum demand usage highlighted in blue. 2. Maximum demand usage highlighted in yellow. 3. Building'A' demand usage ezperlenced far each month. AVCP RHA Campus - Wind Energy Study Bethel, Alaska AVCP RHA kWh Demand History - Building B 1111191071121171071 tt21/OS 2119108 3t19J08 4121108 5/191081 V191081 71211081 81191081 9118f08 1 10/20/08 Remarks Apart #17 371 436 543 4251 3621 3971 326 298 289 'r°3 3011 349 Apart 918 1 24D 1 1 2201 3161 2961 3111 3271 2241 2851 2311 2381 2721 292 Apart#19 1 2%1 3131 3961 3231 Y0,91 3331 2621 3311 3241 2731 268 334 Apart#40 1 Mol 1921 3421 3241 1901 1841 U91 1631 1531 1431 151 2t3 ota mont1101 , 6 . . t , See Mote 3 we. kWhfmonth 277 290 399 342 2931i 310 2401 269 Ii 2491 2621 Z481 297 Total kWhlyear I 13,908 iv'¢tes: 1. P,Sinimum demand usage highlighted in blue. 2. Maximum demand usage highlighted in yellow- 3. Building Us total demand usage experienced each month. AVCP RHA kWh Demand History -Building C 11119/Q7 12117/07 11121/081 2/1910 91081 61191081 U211081 81201081 9118/08 10120108 Remarks ;part#5 381 329 4571 3B41 2091 3441 250 294 274 275 302 420 Apart#6 210 223 2301 1541 2191 1871 992 146 185 174 146 156 Apart#7 2ih3 228 231 1931 1181 1661 223 260 237 211 64 708 .Daft #8 20 30 60 5o 30 40 40 260 310 no 330 480 Apart#9 416 400 431 331 362 401 336 340 360 297 141 64 Apart#10 540 474 587 ?25 472 475 397 401 446 435 435 513 otal kWhImonth. 6 ,5201 1 t6l 31 113101 Ij/01 1 14813 11714 1 e4l 81 Ij41 ISee Note 3 Ave.kWhimonth 2951 2921 3331 3061 2531 2691 2181 2841 3021 2861 2361 290 Total kWhlyear 1 20,184 N¢tas: 1. Minimum demand usage high€Sghted in blue. 2. Maximum demand usage highlighted in yellow. 3. Building Cs total demand usage experienced each month.. AVCP RHA kWh Demand History -Building D 11t19107 12f97107 1121108 2719108 3119/08 412i108 5N9108 6119/08 712i108 81i9108 9118106 iQt20108 Remarks part#11 3281 3821 6561 5171 3321 1291 2531 2731 2721 2281 2241 322 Apart #12 363 382 4701 3711 3301 a571 2101 274 2171 2011 2361 273 Apart413 62 150 123 99 89 89 71 59 56 77 6 30 Rpart#14 40o d30 530 440 390 430 330 350 320 350 340 370 +part#15 414 416 35DI 3281 2931 3Z21 2361 1701 12tj 1301 1511 129 Apart#is 448 486 6421 4311 3611 3721 2931 2341 3631 2421 3571 350 mont .10 See i,tc3e 3 Ave.kWhlmontlt 336 374 462 359 295 325 232 227 225 195 219 246 TEE otal kWhlyear 20,990 Notes: 1_ k4snimunl demand usage highlighted in blue. 2_ Maximum demand usage hyhit ghted in yel€wr. 7. $ui ding f3's total demand usage exile enced each m¢nih. AVCP RHA Campus - Wind Energy Study Bethel, Alaska AVCP RHA kWh Demand History - Building E 111119107112JI71071 11211081 21191081311910814121/081 5119fo8l 61191081 W211081 W191081 9118108 10120/08 lRemarks Apart#21 150 130 143 179 171 236 153 1021 44 80 119 348 part#22 47 43 48 37 39 108 130 130 103 63 99 195 Apat#23 155 184 252 50 148 168 191 210 222 209 225 278 Hpart V24 288 271 318 319 227 279 230 346 151 155 214 276 Apart #25 230 205 25 169 `:64 173 163 167 153 113 154 228 7Wart#26 1€d 179 221 180 163 191 169 159 195 139 139 150 Apart#27 334 361 3£6 299 296 378 278 297 343 300 321 3£4 !apart#26 147 114 187 155 15o 187 157 163 165 144 144 143 Apart#29 1 180 1541 2011 167 1921 1781 134 139 17PI 116 166 195 Apart#30 180 2451 3461 315 2801 2891 236 1 2461 2561 22.111 2391 265 Part#31 63 59 78 56 51 97 184 183 187 162 177 A A43an#32 333 307 3371 248 2491 235 2211 2931 266 313 tarr;dry Rm 11196 1.090 1.274 1,033 9751 11126 938 9781 0.451 W7 1,W2 1 248 b€ech Rm 2,741 2.5cA 3A071 2,626 2,551 2,892 Z,3081 Z2371 21045 1 M31 11907 2a'32 mat lmon ' , . . 6,126 See Note 3 Ave. kWhlmonth 444 422 528 426 404 470 393 398 381 343 374 480 Total kWhlyear 70,891 Hates: 1- iv3krmum demand usage highlighted in blue. 2. Mavmum demand usage highlighted m yek rre_ 3_ Building Es total demand usaged toe each month.. AVCP RHA kWh Demand History -Lulu Heran Building 11120107 112t18107 V23108 2I20108 3130108 4121108 5t19J08 6fi9t081 8120108 1 9/19I08 10121/00 Remarks Apad#1 374 360 250 170 220 260 240 120 150 100 80 60 Apart#2 206 176 234 185 184 205 172 192 196 166 168 174 Apart#3 128 117 321 342 179 311 235 228 139 100 82 76 ?,patt#4 330 303 363 285 278 313 256 284 335 303 282 298 Apart#5 370 279 168 130 138 129 110 90 84 77 59 65 .a #6 122 235 226 220 237 185 202 277 282 272 255 2:9 ; W #7 448 410 569 397 400 472 386 439 430 351 370 353 Apatt#8 289 275 2,07 270 278 326 283 310 320 283 335 342 .apart#9 320 4801 470 360 3701 320 4701 4101 480 4101 450 510 Apart#10 Ile 151 182 66 65 176 202 2G81 169 223 225 260 Part#11 286 251 347 248 116 1F4 144 248 249 153 167 288 Apart#12 342 336 352 295 286 307 296 375 364 247 269 365 Apart 913 123 123 148 112 127 165 231 411 560 428 529 321 Apart#14 125 tit 147 #to 251 239 194 254 262 225 225 262 Apart#15 128 214 304 247 275 228 173 187 194 177 190 201 part#16 83 72 97 76 80 89 79 138 292 272 279 29Il Sc4erRoom 5,880 5,923 6,080 51840 5,640 5,880 57720 6.400 6,290 6,003 ,640 5,C401 5,600 Total kWhimonth 1 95666 91814 %5651 91354 %1251 91768 91393 10,570 10,746 9*7871 10,6051 10,772 See hate3 /Lve.kWhtmonth 569 5771 6211 5501 5371 5751 5531 6221 6321 5761 6241 634 Total kWhlyear I 120,165 Ncies: 1_ ht=nimurl aSzmand usage h10k7isted in htue- 2, hiaximunl .kmand u>a� hghlighied in yellox�. 3. Lulu Hero*E Euitding dem,ane usage e>perferxed or each rxm61. AVCP RHA Campus - Wind Energy Study Bethel, Alaska Appendix C — Recommended Practices Ill, AWEVS RECOMMENDATIONS Model Zoning Ordinance: Permitted Use Regulation for Small Wind Turbines Recommended Practices The American Wind Energy Association offers a Model Zoning Ordinance to help local officials update ordinances govemingsmall wind turbine instaliations?' The following template serves as a starting point that can save planning and permitting staff valuable time. However, states often have unique subsidies or other programs designed to encourage on -site electricity generation, and local ordinances need to be fine-tuned to accommodate both existing state laws and local regulations. A list of practices recommended by the authors of this book are on page 29. SECTION t PURPOSE: It is the purpose of this regulation to promote the renewable energy systems including rebates, net safe, effective, and efficient use of small wind energy metering, property tax exemptions, tax credits, and systems installed to reduce the on�site consumption solar easements [as appropriate]. However, many of utility supplied electricity. existing zoning ordinances contain restrictions which, while not intended to discourage the installation of SECTlON,2 FINDINGS: small wined turbines, can substantially increase the time and costs required to obtain necessary The [city or county] finds that wind energy is an constriction permits. abundant, renewable, and nonpolluting energy resource and that its conversion to electricity will Therefore, we find that it is necessary to standardize reduce our dependence on non-renewable energy and streamline the proper issuance of building resources and decrease the air and water pollution permits for small wind energy systems so that this that results from the use of conventional energy clean, renewable energy resource can be utilized in sources. Distributed small wind energy systems will a cost=effective and timely manner. j also enhance the reliability and power duality of the power grief, reduce peak power demands, and help SECTION 3 DEFINITIONS: diversify the State's energy supply portfolio. Small Small liilEnd Energy System: A wind energy Con - wind systems also make the electricity supply market more competitive by promoting customer choice. version system consisting of a wind turbine, a tower, and associated control or conversion electronics, The State of has enacted a number of laws which has a rated capacity of not more than [ and programs to encourage the use of small-scale 100 kW/1 MWI and which is intended primarily to reduce on -site consumption of utility pourer. 27. Available online at: www.awea.org/smallWind/documents/modelzo.htmi rr,,,z"".a.,�'"'...�.�z '<� ,z".,sa„ RSA Engineering, Inc. Page 20 AVCP RHA Campus - Wind Energy Study Bethel, Alaska Tower Height; The height above grade of the fixed 4.5 Compliance with Uniform Building Code, portion of the tower, excluding the wind turbine itself. Building permit applications for small wind energy systems shall be accompanied by standard drawings SECTION'4 PERMITTED USE: of the wind turbine structure, including the tower; Small wind energy systems shall be a permitted use base, and footings. An engineering analysis of the in all zoning classifications where structures of any tower showing compliance with the Uniform Building sort are allowed, subject to certain requirements as Code and certified by licensed professional engineer set forth below: shall also be submitted. This analysis is frequently supplied by the manufacturer. Wet stamps shall not 4.1 Tower Height For property sizes between V2 be required. acre and one acre the tower height shall be limited to,[80 ft/150 ft]. For property sizes of one 4.6 Compliance with FAA Regulations: Small wind acre or more, there is no limitation on tower height, energy systems must comply with applicable FAA except as imposed by FAA regulations. regulations, including any necessary approvals for installations close to airports. 4.2 set -back: No part of the wind system structure, 4_7 Compliance with National Electric Code: including guy wire anchors, may extend closer than ten (10) feet to the property boundaries of the Building permit applications for small wind energy installation site. systems shall be accompanied by a line drawing of the electrical Components in sufficient detail to allow 4.3 Noise. For wind speeds in the range of 0-25 for a determination that the manner of installation mph, small wind turbines shall not cause a sound conforms to the National Electrical Code. This infor- pressure level in excess of 60 dB(A), or in excess of oration is frequently supplied by the manufacturer. 5 dB(A) above the background noise, whichever is greater, as measured at the closest neighboring 4.8 utility Notification: No small wind energy system inhabited dwelling. This level, however, may be shall be installed until evidence has been given that exceeded during short-term events such as utility the utility company has been informed of the outages and severe wind storms. customer's intent to install an interconnected customer -awned generator. Offgrid systems shall be 4.4 Approved Wind Turbines: Small wind turbines exempt from this requirement. must have been approved under the Emerging Renewables Program of the California Energy Commission or any other small wind certification Examples of State Zoning and Easement Laws. program recognized by the American Wind Energy See AWEA's online toolbox for finks to California, Association. Minnesota, Montana and Nebraska policies: www.awea,org/smallwind/toolbox/default.asp RSA Engineering, Inc. Page 21 AVCP RHA Campus - Wind Energy Study Bethel, Alaska Glossaries Ampere -hour — A unit for the quantity of electricity obtained by integrating current flow in amperes over the time in hours for its flow; used as a measure of battery capacity. Anemometer — A device to measure the wind speed. Average wind speed —The mean wind speed over a specified period of time. Blades — The aerodynamic surface that catches the wind. Cut -in wind speed — The wind speed at which a wind turbine begins to generate electricity. Cut-out wind speed —The wind speed at which a wind turbine ceases to generate electricity. Grid —The utility distribution system. The network that connects electricity generators to electricity users. Interconnection — A process of linking a generator, like some types of small wind system, to the electric grid. Interconnection requires permission from the local utility, and rules for doing so often differ on a case -by -case basis. Inverter — A device that converts direct current (DC) to alternating current (AC). kW — Kilowatt, a measure of power for electrical current (1,000 watts). kWh —Kilowatt-hour, a measure of energy equal to the use of one kilowatt in one hour. O & M Cost —Operation and maintenance costs. Power coefficient —The ratio of the power extracted by a wind turbine to the power available in the wind stream. PUC —Public Utility Commission, a state agency which regulates utilities. In some areas know as Public Services Commission (PSC). PURPA —Public Utility Regulatory Policies Act (1978), 16 U.S.C. §2601.18 CFR§292 that refers to small generator utility connection rules. Net Metering — A policy implemented by some state or local governments to ensure that any extra electricity produced by a generator, such as a small wind system, can be sent back into the grid for credit. Rated Output capacity —The output power of a wind machine operating at the rated wind speed. Rated wind speed The lowest wind speed at which the rated output power of a wind RSA Engineering, Inc. Page 22 AVCP RHA Campus - Wind Energy Study Bethel, Alaska Rotor — The rotating part of a wind turbine, including either the blades and blades assembly or the rotating portion of a generator. Rotor diameter —The diameter of the circle swept by the rotor. Rotor speed — The revolutions per minute of the wind turbine rotor. Start-up wind speed —The wind speed at which a wind turbine rotor will begin to spin. See also Cut -in wind speed.