Solar Energy Generating Systems

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Solar Energy Generating Systems
Solar Plant kl.jpg
Part of the 354 MW SEGS solar complex in northern San Bernardino County, California.
Solar Energy Generating Systems
CountryUnited States
Location Mojave Desert
Coordinates 35°01′54″N117°20′53″W / 35.0316°N 117.348°W / 35.0316; -117.348
StatusOperational
Construction began1983
Commission date 1984
Owner(s) NextEra Energy Resources
Solar farm
Type CSP
CSP technology Parabolic trough
Collectors 936,384
Site resource2,725 kWh/m2/yr
Site area1,600 acres (647.5 ha)
Power generation
Units operational2
Units decommissioned7
Nameplate capacity 160 MW
Capacity factor 19.2%
Annual net output 539 GW·h (2015)
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Solar Energy Generating Systems (SEGS) is a concentrated solar power plant in California, United States. With the combined capacity from three separate locations at 354 megawatt (MW), it was for thirty years the world's largest solar thermal energy generating facility, until the commissioning of the even larger Ivanpah facility in 2014. It was also for thirty years the world's largest solar generating facility of any type of technology, until the commissioning of the photovoltaic Topaz Solar Farm in 2014. It consisted of nine solar power plants in California's Mojave Desert, where insolation is among the best available in the United States.

Contents

SEGS I–II (44 MW) were located at Daggett ( 34°51′45″N116°49′45″W / 34.86250°N 116.82917°W / 34.86250; -116.82917 ); they have been replaced with a solar photovoltaic farm.

SEGS III–VII (150 MW) were installed at Kramer Junction ( 35°00′43″N117°33′32″W / 35.01194°N 117.55889°W / 35.01194; -117.55889 ); all five SEGS have undergone demolition. [1] [2] [3]

SEGS VIII–IX (160 MW) are located at Harper Lake ( 35°01′55″N117°20′50″W / 35.03194°N 117.34722°W / 35.03194; -117.34722 ). [4] 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. [5] The site of SEGS X was later licensed for a solar photovoltaic farm, Lockhart Solar PV II. [6]

Most of the thermal facilities were retired by 2021, [7] and photovoltaics were built on the same sites.

Plants' scale and operations

Before retirement and replacement of SEGS I-VII with solar photovoltaics, the plants had 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 was around 75 MWe —, representing a 21% capacity factor. In addition, the turbines could be utilized at night by burning natural gas.

NextEra claimed in 2009 that the solar plants could 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 been providеd by fossil fuels, such as oil. [8]

The facilities had a total of 936,384 mirrors and cover more than 1,600 acres (647.5 ha). Lined up, the parabolic mirrors would have extended 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). [9]

Principle of operation

Sketch of a Parabolic Trough Collector Parabolic trough.svg
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.[ citation needed ] 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. [10]

Mirrors

The parabolic mirrors are shaped like quarter-pipes. The sun shines on glass panels, 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, [11] 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, [11] [12] and commissioned between December 20, 1984 and October 1, 1990. [13] After Luz Industries' bankruptcy in 1991 plants were sold to various investor groups as individual projects, and expansion including three more plants was halted. [5]

Kramer Junction employs about 95 people and 45 people work at Harper Lake.[ citation needed ]

SEGS plant history and operational data (1985–1990)
PlantYear
built		LocationTurbine
capacity		Field
area		Oil
temperature		Gross solar production
of electricity (MWh)
Net (MW)Gross (MW)(m2)(°C)198519861987198819891990
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, [14] KJC Operating Company, [15] IEEE, [16] NREL [17] [18]
SEGS plant history and operational data (1991–2002)
Gross solar production
of electricity (MWh)
Plant199119921993199419951996199719981999200020012002average 1998–2002Total
SEGS I20,25217,93820,36820,19419,80019,87919,22818,68611,25017,23517,94717,40216,500348,950
SEGS II35,16832,48136,88236,56635,85335,99534,81733,83633,40831,20732,49731,51132,500571,696
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, [14] KJC Operating Company, [15] IEEE, [16] NREL [17] [18]
SEGS plant history and operational data (2003–2014)
Net solar production
of electricity (MWh)
Plant200320042005200620072008200920102011201220132014average 2003–2014Total
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 (2015–2021)
Net solar production
of electricity (MWh)
Plant2015201620172018201920202021TotalTotal
1985–2021
SEGS I [19] 12,562dec.(PV)(PV)(PV)(PV)(PV)12,562459,943
SEGS II [20] dec.dec.(PV)(PV)(PV)(PV)(PV)0775,399
SEGS III [21] 52,07346,58244,11543,84938,2420dec.224,8611,933,518
SEGS IV [22] 53,11749,03443,18244,40641,8650dec.231,6041,969,301
SEGS V [23] 52,64650,14243,93447,38341,4240dec.235,5291,975,842
SEGS VI [24] 46,93740,92336,38034,26200dec.158,5021,715,812
SEGS VII [25] 37,77130,48032,60127,95600dec.128,8081,599,852
SEGS VIII [26] 138,149140,849123,451132,871120,530114,55781,699852,1064,189,538
SEGS IX [27] 145,863142,867131,268137,564124,375122,045116,013919,9954,161,294
Total539,118500,877454,931468,291366,254236,602197,7122,754,40518,780,499
Starting 2017, SEGS I was replaced by PV system Sunray 2, and SEGS II by PV system Sunray 3

Harper Lake

Until Ivanpah Solar Power Facility was commissioned in 2014, SEGS VIII and SEGS IX, located at 35°01′55″N117°20′50″W / 35.031815°N 117.347270°W / 35.031815; -117.347270 (SEGS VIII and IX) were the largest solar thermal power plants individually and collectively in the world. [28] 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 would have had 80 MW of installed capacity. [29] Abengoa Solar recently constructed the 280MW Mojave Solar Project (MSP) adjacent to the SEGS VIII and SEGS IX plants. [30] The MSP also uses concentrating solar thermal trough technology.

Starting in February 2020, SEGS VIII no longer burned natural gas. The last production month was October 2021. SEGS IX stopped burning natural gas starting October 2020, except for January 2021.

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. Solar Energy Generating Systems at Kramer Junction.jpg
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″N117°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), [15] one of the best in the nation[ citation needed ]. This was the location of SEGS II - VII, which were retired in 2019. As of 2021, they were going to be replaced with a new solar photovoltaic array called Resurgence I. [2] [3]

Daggett

SEGS I and II were located at 34°51′47″N116°49′37″W / 34.8631°N 116.827°W / 34.8631; -116.827 (SEGS I and II) and owned by Cogentrix Energy (Carlyle Group). [31] SEGS II was shut down in 2014 and was replaced by Sunray 3 (EIA plant code 10438), a 13,8 MW photovoltaic system. SEGS I was shut down one year later and replaced by 20 MW PV system Sunray 2 (EIA plant code 10437). [32] [33] Sunray 2 and Sunray 3 started production in 2017 as per EIA data.

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. [34]

See also

Related Research Articles

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References

  1. ↑ "SEGS III – VII - Kramer Junction". California Energy Commission. Retrieved 24 September 2022.
  2. 1 2 "Valley Clean Energy Makes Major Solar, Storage Power Deal".
  3. 1 2 "Resurgence Solar I & II Land Use Services Department Planning Commission Staff Report" (PDF).
  4. ↑ The Energy Blog: About Parabolic Trough Solar
  5. 1 2 "Large Solar Energy Projects". California Energy Commission. Archived from the original on 14 July 2016. Retrieved 14 July 2016.
  6. ↑ ""2021-07-14 Lockhart Solar PV II NOP"" (PDF).
  7. ↑ Cheah, Cindy (21 September 2021). "World's longest-operating solar thermal facility is retiring most of its capacity - Today in Energy - U.S. Energy Information Administration (EIA)". www.eia.gov. Archived from the original on 26 September 2021.
  8. ↑ "Solar Electric Generating System" (PDF). Retrieved 2009-12-13.
  9. ↑ "Reducing the Cost of Energy from Parabolic Trough Solar Power Plants", NREL, 2003
  10. ↑ Penn, Ivan (22 June 2017). "California invested heavily in solar power. Now there's so much that other states are sometimes paid to take it". www.latimes.com. Retrieved 2019-02-25.
  11. 1 2 "Solar thermal power generation". Solel Solar Systems Ltd. Archived from the original on 2008-06-01. Retrieved 2010-09-30.
  12. ↑ 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.
  13. ↑ Solar Electricity Generation in California
  14. 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.{{cite journal}}: Cite journal requires |journal= (help)
  15. 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.{{cite journal}}: Cite journal requires |journal= (help)
  16. 1 2 Kearney, D. (August 1989). "Solar Electric Generating Stations (SEGS)". IEEE Power Engineering Review. 9 (8). IEEE: 4–8. doi:10.1109/MPER.1989.4310850. S2CID   7639056.
  17. 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.{{cite journal}}: Cite journal requires |journal= (help)
  18. 1 2 Solar Electric Generating Station IX. NREL
  19. ↑ EIA Electricity Data Browser - SEGS I
  20. ↑ EIA Electricity Data Browser - SEGS II
  21. ↑ EIA Electricity Data Browser - SEGS III
  22. ↑ EIA Electricity Data Browser - SEGS IV
  23. ↑ EIA Electricity Data Browser - SEGS V
  24. ↑ EIA Electricity Data Browser - SEGS VI
  25. ↑ EIA Electricity Data Browser - SEGS VII
  26. ↑ EIA Electricity Data Browser - SEGS VIII
  27. ↑ EIA Electricity Data Browser - SEGS IX
  28. ↑ Jones, J. (2000), "Solar Trough Power Plants", National Renewable Energy Laboratory. Retrieved 2010-01-04.
  29. ↑ "California Energy Commission - Large Solar Energy Projects". Archived from the original on 2008-05-11. Retrieved 2011-05-02.
  30. ↑ Abengoa Solar - The Mojave Solar Project
  31. ↑ SUNRAY/SEGS Archived 2013-05-16 at the Wayback Machine
  32. ↑ California Solar Energy Statistics & Data
  33. ↑ Permit approved for solar facility Archived 2017-02-13 at the Wayback Machine
  34. ↑ Storage Tank at Solar Power Plant in Desert Explodes; Immediate Area Is Evacuated
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