Solar Energy Generating Systems

Solar Energy Generating Systems
Part of the 354 MW SEGS solar complex in northern San Bernardino County, California.
Country United States
Location Mojave Desert
Coordinates 35°01′54″N 117°20′53″W / 35.0316°N 117.348°W / 35.0316; -117.348Coordinates: 35°01′54″N 117°20′53″W / 35.0316°N 117.348°W / 35.0316; -117.348
Status Operational
Construction began 1983
Commission date 1984
Owner(s) NextEra Energy Resources
Solar field
Type CSP
CSP technology Parabolic trough
Collectors 936,384
Site area 1,600 acres (647.5 ha)
Site resource 2,725 kWh/m2/yr
Power generation
Units operational 9
Units cancelled 3
Units decommissioned 1
Nameplate capacity 361 MW
Capacity factor 19.2%
Annual net output 539 GW·h (2015)

Solar Energy Generating Systems (SEGS) in California, with the combined capacity from three separate locations at 354 megawatts (MW, 474,700 hp), is now the world's second largest solar thermal energy generating facility, after the commissioning of the even larger Ivanpah facility in 2014. It consists of nine solar power plants in California's Mojave Desert, where insolation is among the best available in the United States. SEGS I–II (44 MW) are located at Daggett (34°51′45″N 116°49′45″W / 34.86250°N 116.82917°W / 34.86250; -116.82917), SEGS III–VII (150 MW) are installed at Kramer Junction (35°00′43″N 117°33′32″W / 35.01194°N 117.55889°W / 35.01194; -117.55889), and SEGS VIII–IX (160 MW) are placed at Harper Lake (35°01′55″N 117°20′50″W / 35.03194°N 117.34722°W / 35.03194; -117.34722).[1] NextEra Energy Resources operates and partially owns the plants located at Kramer Junction. On January 26, 2018, the SEGS VIII and IX at Harper Lake were sold to renewable energy company Terra-Gen, LLC. A tenth plant (SEGS X, 80 MW) had been in construction and SEGS XI and SEGS XII had been planned by Luz Industries, but the developer filed for bankruptcy in 1992, because it was unable to secure construction financing.[2]

Plants' scale and operations

The plants have a 354 MW net (394 MW gross) installed capacity. The nameplate capacity, which operating continuously, would dеliver the samе net power output, coming only from the solar source is around 75 MWe —, representing a 21% capacity factor. In addition, the turbines can be utilized at night by burning natural gas.

NextEra claims that the solar plants power 232,500 homеs (during the day, at peak power) and displace 3,800 tons of pollution pеr year that would have been produced if the electricity had bееn providеd by fossil fuels, such as oil.[3]

The facilities have a total of 936,384 mirrors and cover more than 1,600 acres (647.5 ha). Lined up, the parabolic mirrors would extend over 229 miles (369 km).

As an example of cost, in 2002, one of the 30 MW Kramer Junction sites required $90 million to construct, and its operation and maintenance cost was about $3 million per year (4.6 cents per kilowatt hour).[4] With a considered lifetime of 20 years, the operation, maintenance and investments interest and depreciation triples the price, to approximately 14 cents per kilowatt hour.

Principle of operation

Sketch of a Parabolic Trough Collector

The installation uses parabolic trough, solar thermal technology along with natural gas to generate electricity. About 90% of the electricity is produced by the sunlight. Natural gas is only used when the solar power is insufficient to meet the demand from Southern California Edison, the distributor of power in southern California.

Mirrors

The parabolic mirrors are shaped like quarter-pipes. The sun shines onto the panels made of glass, which are 94% reflective, unlike a typical mirror, which is only 70% reflective. The mirrors automatically track the sun throughout the day. The greatest source of mirror breakage is wind, with 3,000 mirrors typically replaced each year. Operators can turn the mirrors to protect them during intense wind storms. An automated washing mechanism is used to periodically clean the parabolic reflective panels. The term "field area" is assessed as the actual collector area.

Heat transfer

The sunlight bounces off the mirrors and is directed to a central tube filled with synthetic oil, which heats to over 400 °C (750 °F). The reflected light focused at the central tube is 71 to 80 times more intense than the ordinary sunlight. The synthetic oil transfers its heat to water, which boils and drives the Rankine cycle steam turbine,[5] thereby generating electricity. Synthetic oil is used to carry the heat (instead of water) to keep the pressure within manageable parameters.

Individual locations

The SEGS power plants were built by Luz Industries,[5][6] and commissioned between December 20, 1984 and October 1, 1990.[7] After Luz Industries' bankruptcy in 1991 plants were sold to various investor groups as individual projects, and expansion including three more plants was halted.[2]

Kramer Junction employs about 95 people and 45 people work at Harper Lake.

SEGS plant history and operational data (1985-1990)
Plant Year
built		 Location Turbine
capacity		 Field
area		 Oil
temperature		 Gross solar production
of electricity (MWh)
Net (MW) Gross (MW) (m²) (°C) 1985 1986 1987 1988 1989 1990
SEGS I1984Daggett141482,96030719,26122,51025,05516,92723,52721,491
SEGS II1985Daggett3033190,33831625,08523,43138,91443,86239,156
SEGS III1986Kramer Jct.3033230,30034949,44461,47563,09669,410
SEGS IV1986Kramer Jct.3033230,30034952,18164,76270,55274,661
SEGS V1987Kramer Jct.3033250,50034962,85865,28072,449
SEGS VI1988Kramer Jct.3035188,00039048,04562,690
SEGS VII1988Kramer Jct.3035194,28039038,86857,661
SEGS VIII1989Harper Lake8089464,340390114,996
SEGS IX1990Harper Lake8089483,9603905,974
Total3543942,314,97819,26147,595150,111244,937353,230518,487
Sources: Solargenix Energy,[8] KJC Operating Company,[9] IEEE,[10] NREL[11][12]
SEGS plant history and operational data (1991-2002)
Gross solar production
of electricity (MWh)
Plant 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 average 1998–2002 Total
SEGS I20,25217,93820,36820,19419,80019,87919,22818,68611,25017,23517,94717,40216,500331,550
SEGS II35,16832,48136,88236,56635,85335,99534,81733,83633,40831,20732,49731,51132,500549,159
SEGS III60,13448,70258,24856,89256,66364,17064,67770,59870,68965,99469,36966,12568,555995,686
SEGS IV64,60051,00758,93557,79554,92961,97064,50371,63571,14263,45764,84270,31368,2781,017,283
SEGS V59,00955,38367,68566,25563,75771,43975,93675,22970,29373,81071,82673,23572,8791,014,444
SEGS VI64,15547,08755,72456,90863,65071,40970,01967,35871,06668,54367,33964,48367,758878,476
SEGS VII58,37346,94054,11053,25161,22070,13869,18667,65166,25864,19564,21062,19665,048834,986
SEGS VIII102,464109,361130,999134,578133,843139,174136,410137,905135,233140,079137,754138,977137,9901,691,773
SEGS IX144,805129,558130,847137,915138,959141,916139,697119,732107,513128,315132,051137,570125,0361,594,852
Total608,960538,458613,798620,358628,674676,091674,473662,631636,851652,835657,834662,542654,5398,967,123
Sources: Solargenix Energy,[8] KJC Operating Company,[9] IEEE,[10] NREL[11][12]
SEGS plant history and operational data (2003-2014)
Net solar production
of electricity (MWh)
Plant 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 average 2003–2014 Total
SEGS I6,9138,4216,3365,559010,7059,03310,64811,16411,6669,4038,5838,20398,431
SEGS II11,14214,58213,3757,5475,44528,04018,63522,82926,19825,12623,1737,61116,975203,703
SEGS III59,02764,41356,68051,72159,48069,01262,97160,02961,35056,87756,82454,40759,399712,791
SEGS IV58,10062,00656,34952,43959,79969,33863,56363,08457,68462,41458,31754,32159,785717,414
SEGS V61,92167,71762,30953,47159,54769,31659,82054,32860,45162,87757,75856,35460,489725,869
SEGS VI50,50453,61851,82745,07665,83267,15662,75063,57659,32756,08252,53950,54756,570678,834
SEGS VII49,15450,47946,62842,05058,30765,18558,95058,83657,37854,14748,18346,76253,005636,059
SEGS VIII119,357124,089120,282117,451122,676135,492131,474155,933152,463145,247141,356145,525134,2791,611,345
SEGS IX115,541123,605120,915117,310122,699150,362139,756163,899160,506164,203154,082147,883140,0631,680,761
Total531,659568,930534,701492,624553,785664,606606,952653,162646,521638,639601,635571,993588,7677,065,207
SEGS plant history and operational data (2015)
Net solar production
of electricity (MWh)
Plant 2015 Total Total
1985–2015
SEGS I[13]12,56212,562 442,543
SEGS II[14] 752,862
SEGS III[15]52,07352,073 1,760,550
SEGS IV[16]53,11753,117 1,787,814
SEGS V[17]52,64652,646 2,747,851
SEGS VI[18]46,93746,937 1,651,282
SEGS VII[19]37,77137,771 1,551,591
SEGS VIII[20]138,149138,149 2,465,981
SEGS IX[21]145,863145,863 3,352,060
Total539,118539,118 16,512,534

Harper Lake

SEGS VIII and SEGS IX, located at 35°01′55″N 117°20′50″W / 35.031815°N 117.347270°W / 35.031815; -117.347270 (SEGS VIII and IX), until Ivanpah Solar Power Facility commissioning in 2014, were the largest solar thermal power plants individually and collectively in the world.[22] They were the last, the largest, and the most advanced of the nine plants at SEGS, designed to take advantage of the economies of scale. Construction of the tenth plant in the same locality was halted because of the bankruptcy of Luz Industries. Construction of the approved eleventh and twelfth plants never started. Each of the three planned plants had 80 MW of installed capacity.[23] Abengoa Solar recently constructed the 280MW Mojave Solar Project (MSP) adjacent to the SEGS VIII and SEGS IX plants.[24] The MSP also uses concentrating solar thermal trough technology.

Kramer Junction

The reflectors at Kramer Junction site facing the western sky to focus the late afternoon sunlight at the absorber tubes partially seen in the picture as bright white spots.

This location (35°00′48″N 117°33′38″W / 35.013218°N 117.560531°W / 35.013218; -117.560531 (SEGS III–VII)) receives an average of 340 days of sunshine per year, which makes it an ideal place for solar power generation. The average direct normal radiation (DNR) is 7.44 kWh/m²/day (310 W/m²),[9] one of the best in the nation.

Daggett

SEGS I and II are located at 34°51′47″N 116°49′37″W / 34.8631°N 116.827°W / 34.8631; -116.827 (SEGS I and II) and are owned by Cogentrix Energy (Carlyle Group).[25] SEGS II was shut down in 2014 and will be replaced with 44 MW of photovoltaics, Sunray Energy 2.[26]

Accidents and incidents

In February 1999, a 900,000-US-gallon (3,400 m3) Mineral Oil storage tank exploded at the SEGS I (Daggett) solar power plant, sending flames and smoke into the sky. Authorities were trying to keep flames away from two adjacent containers that held sulfuric acid and sodium hydroxide. The immediate area of 0.5 square miles (1.3 km2) was evacuated.[27]

See also

References

  1. ↑ The Energy Blog: About Parabolic Trough Solar
  2. 1 2 "Large Solar Energy Projects". California Energy Commission. Archived from the original on 14 July 2016. Retrieved 14 July 2016.
  3. ↑ "Solar Electric Generating System" (PDF). Retrieved 2009-12-13.
  4. ↑ "Reducing the Cost of Energy from Parabolic Trough Solar Power Plants", NREL, 2003
  5. 1 2 "Solar thermal power generation". Solel Solar Systems Ltd. Archived from the original on 2008-06-01. Retrieved 2010-09-30.
  6. ↑ Alexis Madrigal (November 16, 2009). "Crimes Against the Future: The Demise of Luz". Inventing Green. Archived from the original on 2011-07-11. Retrieved 30 September 2010.
  7. ↑ Solar Electricity Generation in California
  8. 1 2 Cohen, Gilbert (2006). IEEE May Technical Meeting, ed. "Nevada First Solar Electric Generating System" (PDF). Las Vegas, Nevada: Solargenix Energy: 10. Archived from the original (PDF) on 2009-03-18.
  9. 1 2 3 Frier, Scott (1999). An overview of the Kramer Junction SEGS recent performance, ed. "Parabolic Trough Workshop" (PDF). Ontario, California: KJC Operating Company. Archived from the original (PDF) on 2008-10-15.
  10. 1 2 Kearney, D. (August 1989). "Solar Electric Generating Stations (SEGS)". IEEE Power Engineering Review. IEEE. 9 (8): 4–8. doi:10.1109/MPER.1989.4310850.
  11. 1 2 Price, Hank (2002). Parabolic trough technology overview, ed. "Trough Technology - Algeria" (PDF). NREL: 9. Archived from the original (PDF) on 2008-10-20.
  12. 1 2 Solar Electric Generating Station IX. NREL
  13. ↑ EIA Electricity Data Browser - SEGS I
  14. ↑ EIA Electricity Data Browser - SEGS II
  15. ↑ EIA Electricity Data Browser - SEGS III
  16. ↑ EIA Electricity Data Browser - SEGS IV
  17. ↑ EIA Electricity Data Browser - SEGS V
  18. ↑ EIA Electricity Data Browser - SEGS VI
  19. ↑ EIA Electricity Data Browser - SEGS VII
  20. ↑ EIA Electricity Data Browser - SEGS VIII
  21. ↑ EIA Electricity Data Browser - SEGS IX
  22. ↑ Jones, J. (2000), "Solar Trough Power Plants", National Renewable Energy Laboratory. Retrieved 2010-01-04.
  23. ↑ California Energy Commission - Large Solar Energy Projects
  24. ↑ Abengoa Solar - The Mojave Solar Project
  25. ↑ SUNRAY/SEGS Archived 2013-05-16 at the Wayback Machine.
  26. ↑ Permit approved for solar facility Archived 2017-02-13 at the Wayback Machine.
  27. ↑ Storage Tank at Solar Power Plant in Desert Explodes; Immediate Area Is Evacuated
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.