Solar Thermal Energy - STE

Solar thermal energy (STE) is a technology for harnessing solar energy for thermal energy (heat). Solar thermal collectors are classified by the USA Energy Information Administration as low, medium, or high-temperature collectors. Low temperature collectors are flat plates generally used to heat swimming pools. Medium-temperature collectors are also usually flat plates but are used for heating water or air for residential and commercial use. High temperature collectors concentrate sunlight using mirrors or lenses and are generally used for electric power production. STE is different from photovoltaics, which convert solar energy directly into electricity.

The solar thermal method uses energy from the sun directly to generate heat. Solar panels can be used to collect heat from the sun to capture its heat and transfer it for water and space heating in buildings.

Commonly such panels are positioned to maximise absorption of heat from the sun throughout the day and contain tubing through which water circulates. This tubing is known as solar thermal collectors There is also an indirect method where not water but a non-toxic anti-freeze liquid is used. The sun warms this liquid which in turn transfers this heat to water held in a tank. Passive thermal building design is as simple as designing to maximise the sun’s use.

Pocking Solar Park

The Pocking Solar Park is a 10 megawatt (MWp) solar power plant. Construction and assembly of the photovoltaic power plant started in August 2005 and was completed in March 2006. On the former military training area in the Lower-Bavarian town of Pocking, sheep are now grazing under and around the 57,912 photovoltaic modules.

Hoya de Los Vicentes Solar Plant

The Hoya de Los Vicentes Solar Plant (Parque Solar Hoya de Los Vicentes) is a photovoltaic power station in Jumilla, Murcia in Spain. The solar park covers area of some 100 hectares (250 acres) and comprises a group of 200 photovoltaic arrays with a total capacity of 23 MW. A total of 120,000 solar panels have been installed in the facility. The project generates energy equivalent to the annual consumption of 20,000 households.

Abertura Photovoltaic Power Station

Abertura Photovoltaic Power Station is a photovoltaic power station in the municipality of Abertura, Cáceres in Spain. It has a total capacity of 23.1 MWp. The solar park was built by Iberinco. Double axes solar trackers were provided by Mecasolar and Inspira. The financing consortium wass led by West LB, Bank of Scotland and Dexia. A technical advisor was Sylcom Solar.

Lucainena de las Torres Photovoltaic Power Station

The Planta fotovoltaica de Lucainena de las Torres is a photovoltaic power station in Lucainena de las Torres, Almería in Spain. It consists of different units. Lucainena de las Torres 1 has a total capacity of 7.4 MWp and its annual output is about 11.42 GWh. Planta fotovoltaica de Lucainena de las Torres was commissioned in July 2008. Lucainena de las Torres 2 has a total capacity of 7.9 MWpand its annual output is about 12.236 GWh.

Arnprior Solar Generating Station

The Arnprior Solar Generating Station is a 23.4 MW solar farm developed on two adjacent properties located near the town of near Arnprior, Ontario, Canada.

The total project size is expected to be 80 MW, and upon completion it will become one of the largest projects worldwide. The current project phase consists of 312,000 Photovoltaic thin film solar panels made by First Solar and mounted on 13,000 racks on a 200 acres (81 ha) field.

EDF EN Canada developed the project on two adjacent properties as part of the province's Renewable Energy Standard Offer Program, which provides a generous feed-in tariff of €0.2821/kWh for ground-mounted systems of or over 10MW for a period of 20 years.

Tristan Grimbert, president and CEO of EDF EN Canada and all EDF EN affiliates in North America, said, "Arnprior proves the unique abilities of EDF EN Canada to commercialize a flagship solar PV project in a matter of a few months. Our relationship lenders once again have demonstrated their support of our efforts and renewable energy. We look forward to applying our resources, experience and partnership capabilities to the FIT ground mount and rooftop development in 2010 and beyond."

EDF EN Canada has also executed term financing agreements with Dexia and Union Bank, N.A for the project.

"It has been our pleasure to support EDF EN over the years, and particularly with this project," said Lance Markowitz, senior vice president at Union Bank and manager of leasing and asset finance. "We are particularly excited to have played a key role in the financing of the Arnprior Solar Project as it extends EDF EN's leadership in the renewable energy industry to the Canadian solar market."

Alban de La Selle, managing director and head of Dexia Credit Local Canada Branch added, "Dexia is very pleased to take this opportunity to further evidence its commitment to finance the solar energy sector, where the bank has long been a pioneer in Europe. The Arnprior Solar Project will certainly be a landmark in the growing solar industry in Ontario, and we hope it will blaze the trail for many others under an appropriately tailored FIT program, and hopefully for other Canadian provinces."

Montalto di Castro Photovoltaic Power Station

The Montalto di Castro photovoltaic power station is a photovoltaic power station at Montalto di Castro in Viterbo, Italy. The project was developed by the independent developer SunRay that was later acquired by SunPower. Construction was completed and the power station was connected to the grid in November 2009. It cost €120 million.

The Montalto di Castro photovoltaic power station has a capacity of 24 MW. It uses 78,720 SunPower solar panels as well as its tracker systems. As planned, the solar panels will be added on until it reaches 100 MW.

Sinan Solar Power Plant

The Sinan solar power plant is a 24 MW photovoltaic power station in Sinan, Jeollanam-do, South Korea. As of 2009, Sinan solar power plant is the largest photovoltaic installation in Asia. The project was developed by the German company Conergy and it cost US$150 million. It was built by the Dongyang Engineering & Construction Corporation.

The photovoltaic (PV) solar cells that will be used in the project are being suppling by Sun Technics Germany, a wholly owned subsidiary of Conergy AG. The project of Sinan solar power plant will sell the estimated annual 27,000 MWh of electricity pursuant to a fixed tariff arrangement with a Korea Government department for 15 years. The electricity produced will be enough to power more than 6,000 houses.
The proposed size of the photovoltaic field which will track the sun is around 600,000m2. There will be around 109,000 PV modules installed by Sun Technics.
Chul Bohm Kim, Head of Project Finance in Korea and Shane Bush, Global Head of Renewable Energy, were the project team leaders. Shane Bush said “as South Korea implements its strategy to increase renewable energy to 10% of supply by 2020, Standard Chartered is proud to be a leading contributor to the achievement of this goal. The Bank is unique in that it has a dedicated renewable energy team which works with local professionals to offer tailor made solutions for clients.”

DeSoto Next Generation Solar Energy Center

The DeSoto Next Generation Solar Energy Center is a photovoltaic solar power facility in Arcadia, DeSoto County, Florida owned by Florida Power & Light (FPL). President Barack Obama attended the plant's commissioning on October 27, 2009. With a nameplate capacity of 25 megawatts (MW) DC, it is the largest solar photovoltaic plant in the USA as of 2009. It produces an estimated 42,000 megawatt-hours (MW·h) of electricity per year (an average output of about 4.8 MW).

The DeSoto Next Generation Solar Energy Center cost $150 million to construct. The photovoltaic solar power plant consists of over 90,000 SunPower solar panels with single-axis trackers on 180 acres (70 ha).

DeSoto Next Generation Solar Energy Center
Country United States
Locale Arcadia, DeSoto County, Florida
Coordinates 27°19′N 81°48′W / 27.317°N 81.8°W / 27.317; -81.8Coordinates / 27.317; -81.8
Status Operational
Commission date October 27, 2009 (October 27, 2009)
Construction cost $150 million
Owner(s) Florida Power & Light

Solar farm information
Type Flat-panel PV
Photovoltaic modules 90,000 SunPower solar panels

Power generation information
Installed capacity 25 MW
Capacity factor 19%
Annual generation 42 GW·h

Fuente Álamo Solar Power Plant

Planta Solar Fuente Álamo is a photovoltaic power station in Fuente-Álamo, Murcia in Spain. Planta Solar Fuente Álamo covers an area of 62 hectares (150 acres). The power station has a capacity of of 26 megawatts and its annual output is 44 GWh, equivalent to supply electricity to 13,000 households.

The project was developed and constructed by Gestamp Solar. It was later acquired by FRV. The power station cost nearly €200 million and it was commissioned in 2008.

Fuente Álamo Solar Power Plant
Official name Planta Solar Fuente Álamo
Country Spsin
Locale Fuente-Álamo, Murcia
Commission date 2008
Construction cost €200 million
Owner(s) FRV
Developer(s) Gestamp Solar

Solar farm information
Type PV

Power generation information
Installed capacity 26 MW

Dulcinea Solar Plant

The Dulcinea Solar Plant (Planta Solar Dulcinea) is a photovoltaic power station in Cuenca, Spain. Dulcinea Solar Plant consists of 300 photovoltaic generating units with a total capacity of 31.8 MW. The solar power station covers area of 230,324 m2 (2,479,186.9 sq ft). Dulcinea Solar Plant is equipped with 82,896 Kyocera KC-200-GHT2 photovoltaic modules, 6,078 Kyocera KD-210-GHP2 modules, and 66,286 Suntech STP-210/18Ud modules. 6,600 strings of 24 photovoltaic panels linked in series 300 SMA SC100-Outdoor inverters. The estimated available radiation of 1,810 kWh/m2 per year is 1,497 peak sunlight hours.

Dulcinea Solar Plant
Country Spain
Locale Cuenca
Status Operational
Constructor(s) Kyocera

Solar farm information
Type PV
Photovoltaic modules 82,896 x KC-200-GHT2
6,078 x KD-210-GHP2
66,286 x STP-210/18Ud

Power generation information
Installed capacity 31.8 MW

Arnedo Solar Plant

The Arnedo Solar Plant is a solar photovoltaic power plant located in Arnedo, La Rioja, Spain. The 34 MW plant is equipped with 172,000 panels. The Arnedo Solar Plant completed in October 2008, power plant that produces 3approximately 49,936,510 kWh annually, which would own 12,000 households and prevent 375,000 tons of CO2. Facilities in seven acres and 172,000 panels houses. Project budget of about € 180,000,000. La Rioja, a region of Spain known for its wine, already covers 62% of electricity with enhanced resources.

Arnedo Solar Plant
Official name Planta Solar Arnedo
Country Spain
Locale Arnedo, La Rioja
Status Operational
Commission date 2008 (2008)
Developer(s) T-Solar

Solar farm information
Type Flat-panel PV
Photovoltaic modules 172,000

Power generation information
Installed capacity 34 MW
Annual generation 49.9 GWh

Planta Solar La Magascona & La Magasquila

The Planta Solar La Magascona and La Magasquila is a photovoltaic power station located at La Magascona, Trujillo in Cáceres, Spain. It covers 100 hectares (250 acres) and it has a peak output of 23.04 MW. The photovoltaic power plant produces approximately 46 GWh of electricity per year. It was commissioned in July 2007.

Waldpolenz Solar Park

Waldpolenz Solar Park, which is the world’s largest thin-film photovoltaic (PV) power system, was built by German developer and operator Juwi at a former military air base to the east of Leipzig in Germany. The solar power plant is a 40 MW solar power system using state-of-the-art thin film technology, and was fully operational by the end of 2008. 550,000 First Solar thin-film modules from cadmium telluride (CdTe) are being used, which supply about 40,000 MWh of electricity per year.

The installation is located in the Muldentalkreis district in the state of Saxony in eastern Germany, built on half of the location’s 220 hectares in the townships of Brandis and Bennewitz. The investment costs for the Waldpolenz solar park amount to some 130 million euro.

Waldpolenz Solar Park Power plants such at this make renewable energy more affordable for consumers. It is projected that electricity from this installation will be 20 - 40% cheaper than it is at present in Germany.

Finsterwalde Solar Park

The Finsterwalde Solar Park is a photovoltaic power station in Finsterwalde, Germany. It has a capacity of 42 MW. The Finsterwalde Solar Park project is developed by Q-Cells International and LDK Solar and it is equipped with Q-Cells modules and LDK Solar wafers. The project was commissioned in 2009.

Köthen Solar Park

The Köthen Solar Park is a photovoltaic power station in Köthen, Germany. Köthen Solar Park has a capacity of 45 MWp and an annual output of 42 GWh. The solar park is developed built by RGE Energy.

The photovoltaic power station project is built on a former military airfield in Köthen on 116 hectares (290 acres). The project is the largest solar power plant in Saxony-Anhalt and the world's largest with string inverters. The project is equipped 205.000 crystalline photovoltaic modules of BP Solar. The total investment in the project was around €133 millions. The solar park was connected to the grid in 2009.

Moura Photovoltaic Power Station

The Moura Photovoltaic Power Station (Amareleja Photovoltaic Power Station) is a large photovoltaic power station in Amareleja, in the municipality of Moura, Portugal. It is one of the largest power stations of its kind, and is built in one of the sunniest regions in Europe, also one of the most economically depressed region. Its construction involves two stages, the first stage was completed in 2008 after 13 months, the second stage will be completed by 2010. The entire project topped a total cost of €250 million.

Phase-2 of the project involves the construction of a further 20 MW of solar panels. It will occupy an area of 618 acres (250 ha), and will be capable of producing 93 GWh of electrical energy annually (10 MW average - equivalent to the electricity consumption of 15,000 Europeans).

The power station will have an installed capacity of 62 MWp, with a total of over 376,000 solar panels. Approximately 190,000 panels (32 MW) are fitted on fixed structures, and 52,000 panels (10 MW) on fixed on single-axis trackers.

A €7.6 million solar panel factory, located in Moura, was constructed by Acciona, which will provide panels for the second stage of the station construction. Its future production will be targeted at the international market, with a capacity of producing 24 MW of solar panels annually.

Moura Photovoltaic Power Station
Country Portugal
Coordinates 38°11′20″N 07°12′08″W / 38.18889°N 7.20222°W / 38.18889; -7.20222Coordinates: 38°11′20″N 07°12′08″W / 38.18889°N 7.20222°W / 38.18889; -7.20222
Status Operational
Commission date Phase-1: 2008
Phase-2: 2010
Location Amareleja
Fuel type Solar
Technology Photovoltaics
Power generation information
Installed capacity Phase-1: 42 MW
Phase-2: 20 MW

Puertollano Photovoltaic Park

The Puertollano Photovoltaic Park is the fourth largest photovoltaic power station in the world, with a nominal capacity of 47.6 MW. The facility is located in Puertollano, Spain. 476 individual plants with a nominal power of 100 kWp, Suntech and Solaria modules. Fixed structure oriented at 33° south with a total of 231,653 panels.

Renovalia developed this power station in Puertollano, Ciudad Real, housing an energy park with an installed capacity of 50 megawatts (MW). The power generated here is equivalent to the annual domestic consumption of electricity of about 39,000 households. The energy produced here will replace a theoretical discharge of 84,000 tons of CO2/year or, 2.1 million tons of CO2 over the 25 years during it’s production.

Puertollano Photovoltaic Park
Status Operational
Commission date 2008
Owner(s) Renovalia
Location Finca El Quintillo, en el Polígono 16

Puertollano, Ciudad Real, Spain

Technology Photovoltaic
Power generation information
Installed capacity 47.6 MW

Lieberose Photovoltaic Energy Park

The Lieberose Photovoltaic Energy Park is a 53 megawatt (MW) solar photovoltaic power plant in Lieberose, Brandenburg, Germany. The solar park with 700,000 solar panels which went fully on line in October 2009, is the world's third-largest, and will supply electricity for 15,000 households a year while reducing the use of pollution-generating fossil fuels. The Lieberose Solar Park cost $238-million and is operated by the Juwi Group, which has a 20-year contract on the land.

Lieberose Solar Power Plant: an ecological and economic lighthouse project for the protection of climate and nature

The photovoltaic power plant on the former exercise terrain for troops, Lieberose, to the north of Cottbus (Brandenburg) is the largest solar power plant in Germany since 20 August 2009. With the joint assembly of the 560 000 solar modules the Federal Minister Wolfgang Tiefensee, commissioned by the Federal Government for the new Federal states, as well as the Minister-President of Brandenburg Matthias Platzeck made this plant to be the largest photovoltaic park in Germany. In Turnow-Preilack, the juwi Group – project developers for regenerative power plants – together with First Solar – manufacturers of advanced thin-layer modules – are currently realising a photovoltaic power plant with an output of 53 MW on an area of 162 ha that is to be fully connected to the grid by the end of this year. Solarserver hereby presents the second largest photovoltaic plant worldwide and Germany’s No. 1 as Solar System of the Month October 2009.

Strasskirchen Solar Park

The Strasskirchen Solar Park is the second largest photovoltaic power station in the world, with an installed capacity of 54 MW. The facility is located in Straßkirchen, Germany.

Solar cells manufacturer Q-Cells SE (XETRA:QCE) declared on Friday that it has established a joint venture with MEMC Electronic Materials Inc (NYSE:WFR) to build large solar parks in which each partner will have a 50% share.

The first project will be a facility in Strasskirchen, Bavaria and Q-Cells International, a 100%-owned subsidiary of Q-Cells SE, has been commissioned to construct the facility.

German-based Q-Cells SE and MEMC, a US manufacturer of silicon wafers, have agreed to each invest up to around EUR72m in the joint venture in order to cover the bridging finance during the construction phase.

MEMC will supply silicon wafers for the joint venture and Q-Cells will turn them into solar cells.

The Strasskirchen solar park will have a total capacity of around 54 MW and will be the largest ground-mounted PV system in Germany to be operated using crystalline solar cell technology, the companies claim. After completion the project is planned to be sold to an external investor.

Strasskirchen Solar Park
Location Straßkirchen, Germany
Status Operational
Technology Photovoltaic
Installed capacity 54 MW
Annual generation 57 GWh
Commissioned 2009

Olmedilla Photovoltaic Park

The Olmedilla Photovoltaic Park in Olmedilla de Alarcón, Spain, is the world’s largest photovoltaic plant. The Olmedilla Photovoltaic (PV) Park uses 162,000 flat solar photovoltaic panels to deliver 60 megawatts of electricity on a sunny day. It produces enough electricity to power more than 40,000 homes. The entire plant was completed in 15 months at a cost of about $530 million at current exchange rates. Olmedilla was built with conventional solar panels, which are made with silicon and tend to be heavy and expensive. So-called "thin-film" solar panels, although less efficient per square meter, tend to be much cheaper to produce, and they are the technology being tapped to realize the world's largest proposed PV plant, the Rancho Cielo Solar Farm in Belen, N. Mex., which is expected to cost $840 million, cover an area of 700 acres (285 hectares), and produce 600 megawatts of power.

Sarnia Photovoltaic (PV) Power Plant

Sarnia Photovoltaic Power Plant near Sarnia, Ontario in Canada, is as of September 2010 the world’s largest photovoltaic plant with 80 MWp.

20 MWp Phase I was completed in December 2009 and 60 Phase II in September 2010. Plant consists of over 1,000,000 panels. The project is developed by Enbridge.

The Sarnia Photovoltaic Power Plant project was originally proposed by Opti-Solar under the Standard Offer Contract program. Opti-Solar had started contstruction on one of the several 10 MW contracts it had obtained from the Ontario Power Authority.

Opti-Solar failed in the development of its technology and had installed only one MW of its first 10 MW plant when it sold rights to the project to First Solar.

To my knowledge, First Solar is building two 10-MWAC projects using its inhouse thin film product. Canadian Hydro Developers is either the owner now or will be when the project is complete.

Because the contracts are in kWAC the 20 MW project is likely rated at 23 MWDC.

There has been heated debate about this and other large solar PV farms on prime ag land so I thought I'd visit one and see for myself. At least in this case, the project is on the peri-urban fringe of Sarnia with suburbs, stripmalls, malls, and assorted detritus of North American sprawl swallowing the existing ag land. My impression was that this particular project area would have become another mall or something similar and was destined to be bulldozed within a decade.

The site was also near a landfill and if the parcel didn't become a mall it could have become a landfill.

Nevertheless, it was farm land prior to construction and its now fast becoming one of the largest, if not the largest solar PV farms in North America.

Shiraz solar power plant

Shiraz solar power plant is a concentrating solar power type power station situated near Shiraz, Iran which became operational in 2009. The plant uses concentrating parabolic mirrors to focus a beam of light on a tower making steam for electricity generating turbines. It has a capacity of 250 kilowatt hours. It is a pilot project aimed at developing technologies needed for larger solar power plants, and is currently being upgraded to 500 KWh capacity.

The Shiraz solar power plant boasts a modest 250 KW energy production capacity. It’s a solar thermal plant that uses parabolic mirrored troughs to gather sunlight. The mirrors focus the sunlight in an intense ray on a tube that runs the length of the array of mirrors. Inside the tube, a liquid insulated by a vacuum transfers the heat of the mirrors to a traditional generator, where it’s used to produce steam and generate electricity.

Placing an economic value on renewable resources makes sunny Iran rich in solar energy potential. Iran took its first step toward the large scale realization of that potential this week with the inauguration of its first solar energy plant. The plant was constructed with domestic materials and labour in Shiraz, the Fars province.

This solar thermal plant joins some 4,075 small scale solar thermal installations throughout Iran–3,781 residential solar water heaters and 294 public baths heated with solar thermal energy. Iran makes less use of photovoltaic energy, but the Ministry of Energy News Agency mentions a 40 house solar village supplied with photovoltaic energy.

The Iran Daily reports that Iranian energy minister Parviz Fattah sees the Shiraz plant as a first step in Iran’s commitment to solar energy technology, which will increase in Iran along with greater government investment.

“The country backs the use of alternative and renewable energy sources,” said Fattah. “In future alternative energy sources will be greatly developed in the country. The growth of investments in this sphere is expected.”

English information about the Shiraz plant is hard to come by, but more photos of the plant and information in Farsi is available via the Renewable Energy Organization of Iran. Another source, an article in the Tehran Times (no longer available in the paper’s archives, but republished here by a reader) suggests that the completion of the solar plant was several years behind schedule, having been initially slated for the Iranian year 1383 rather than the current year 1387.

Archimede Solar Power Station

Archimede solar power plant is a concentrated solar power plant at Priolo Gargallo near Syracuse in Sicily, Italy. The plant was inaugurated on 14 July 2010. It is the first concentrated solar power plant to use molten salt for heat transfer and storage which is integrated with a combined-cycle gas facility. It uses technology developed by ENEA and Archimede Solar Energy, a joint venture between Angelantoni Industrie and Siemens Energy. Archimede is owned and operated by Enel.

The plant is called "Archimedes" after the rows of huge parabolic mirrors used to capture the sun's rays, which recall the "burning mirrors" that Archimedes is said to have used to set fire to the Roman ships besieging Syracuse during the Siege of Syracuse (214–212 BC).[1] The existing gas-fired power plant on the site was augmented by Archimede. It produces 5 megawatts of electricity, enough for 4,500 families.

The Archimede solar thermal power plant consists of a field of about 30,000 square metres (320,000 sq ft) of mirrors (the parabolic collectors) that concentrate sunlight onto 5,400 metres (17,700 ft) of pipe carrying the molten salt fluid. Molten salt is used as the heat transfer fluid in solar field and is heated to 550 °C (1,022 °F). The thermal energy is then stored in a hot tank and is used to produce high pressure steam to run steam turbines for electricity generation, reducing the consumption of fossil fuels and, as a result, enhancing the environmental performance of the combined-cycle plant. The solar collectors (the parabolic mirrors and pipes or receivers), together with a steam generator and two heat storage tanks – one cold and one hot – make up the solar portion of the system.

When the sun shines, the thermal fluid drawn from the cold tank is circulated through the network of parabolic collectors, where it is heated to a temperature of 550 °C (1,022 °F) and injected into the hot tank, where the thermal energy is stored. The fluid is then drawn from the hot reservoir to produce steam at high pressure and temperature, which is sent to Enel's nearby combined-cycle plant, where it contributes to electricity generation.

This system enables the plant to generate electricity at any time of the day and in all weather conditions until the stored thermal energy is depleted.

The addition of the solar plant to the power station should significantly reduce the amount of gas burnt at the plant and cut carbon dioxide emissions by 7,300 tonnes.

Archimede solar power plant
Country Italy
Town/city Priolo Gargallo
Owner Enel
Status Operational
Fuel Solar
Technology concentrated solar power, combined-cycle gas
Installed capacity 5 MW
Commissioned 2010

Sierra Sun Tower Solar Power

Sierra Sun Tower is a 5 MW commercial concentrating solar power (CSP) plant built and operated by eSolar. The plant is located in Lancaster, California and is the only CSP tower facility operating in North America.

The Sierra SunTower facility is based on power tower CSP technology. The plant features an array of heliostats which reflect solar radiation to a tower-mounted thermal receiver. The concentrated solar energy boils water in the receiver to produce steam. The steam is piped to a steam turbine generator which converts the energy to electricity. The steam out of the turbine is condensed and pressurized back into the receiver.

eSolar unveiled the 5 MW Sierra Sun Tower plant, a commercial facility in Lancaster, California that demonstrates the company's technology. Sierra SunTower is interconnected to the Southern California Edison (SCE) grid and, as of spring 2010, is the only commercial CSP tower facility in North America.

The project site occupies approximately 8 hectares (20 acres) in an arid valley in the western corner of the Mojave Desert at 35° north latitude.

Sierra Sun Tower includes two eSolar modules. 24,000 heliostats, divided between four sub-fields, track the sun and focus its energy onto two tower-mounted receivers. The focused heat converts feedwater piped to the receivers into superheated steam that drives a reconditioned 1947 GE turbine generator to produce electricity. The steam passes through a steam condenser, reverts back to water through cooling, and the process repeats.

During the 12 months of construction, Sierra SunTower created over 300 temporary jobs. In operation, the site employs 21 permanent employees.

Concurrent with the plant’s official unveiling, California Governor Arnold Schwarzenegger praised the eSolar solution, “…proving that California’s energy and environmental leadership are advancing carbon-free, cost-effective energy that can be used around the world.”

Sierra Suntower has been certified by the California Energy Commission as a renewable energy facility. Power from the facility is sold under a Power Purchase Agreement (PPA) with SCE, providing clean, renewable energy for up to 4,000 homes.

The 5 MW output from Sierra SunTower reduces CO2 emissions by 7,000 tons per year, an amount equivalent to planting 5,265 acres of trees, removing 1,368 automobiles from the road, or saving 650,000 gallons of gasoline.

Sierra Sun Tower was designed to validate eSolar's technology at full scale, effectively eliminating scaleup risks. The solar thermal equipment operating at Sierra SunTower forms a blueprint from which future plants will be built.

Sierra Sun Tower Awards

In December 2009, editors of Power Engineering magazine selected Sierra SunTower as the winner of the “Best Renewable Project”. Each year, Power Engineering magazine recognizes the world's best energy projects. The award distinguishes Sierra as an exceptional power generation project toward meeting growing global demand.

In February 2010, Sierra SunTower won Renewable Energy World’s “Renewable Project of the Year” award. The award recognizes eSolar's achievements in the clean energy industry by naming Sierra SunTower an exceptional breakthrough in the commercialization of solar thermal technology.

Kimberlina Solar Thermal Power Plant

The 5 megawatt (MW) Kimberlina Solar Thermal Energy Plant in Bakersfield, California is the first commercial solar thermal power plant to be built by AREVA Solar, formerly Ausra. The Kimberlina renewable energy solar boiler uses Compact Linear Fresnel Reflector (CLFR) technology to generate superheated steam. Each solar boiler has a group of 13 narrow, flat mirrors, that individually track and focus the sun's heat onto overhead pipes carrying water. The water boils directly into steam. The steam can then spin a turbine to generate electricity or be used as industrial steam for food, oil and desalination processes. The Kimberlina solar boiler currently achieves 750-degree F superheated steam. The next generation solar boiler under construction is designed to achieve 900-degree F superheated steam.

AREVA Solar's boiler is the first and only solar boiler certified with an S-Stamp by the American Society of Mechanical Engineers (ASME).

The Kimberlina Solar Thermal Power Plant was the first of its kind to be built in California in more than 20 years, with the previous plant being the Solar Energy Generating Systems, which employs solar troughs.

PS10 Solar Power Tower

Europe's first commercial concentrating Planta Solar 10 or PS10 solar power tower operates near the Southern Spanish city of Seville. The 11 megawatt (MW) solar power tower produces electricity with 624 large movable mirrors called heliostats, it took four years to build and so far cost 35 million Euros.


The mirrors were delivered by Abengoa, the solar receiver was designed and built by Tecnical-Tecnicas Reunidas, a Spanish Engineering Company; and the Solar Tower was designed and built by ALTAC, another Spanish Engineering and Construction Company.


Each of the mirrors has a surface measuring 120 m² (1,292 square feet) that concentrates the sun's rays to the top of a 115 meter (377 ft) high, 40-story tower where a solar receiver and a steam turbine are located. The turbine drives a generator, producing electricity. As of May 2007, this power is three times more expensive than power from conventional sources, but prices are likely to fall, as they have with wind power and as the technologies develop.

Future plans

PS10 is the first of a set of solar power generation plants to be constructed in the same area that will total more than 300 MW by 2013. Power generation will be accomplished using a variety of technologies. The first two power plants to be brought into operation at Sanlúcar la Mayor are the PS10, and Sevilla PV, the largest low concentration system photovoltaic plant in Europe.

Energy storage

The PS10 solar power tower stores heat in tanks as superheated and pressurized water at 50 bar and 285°C. The water evaporates and flashes back to steam, when pressure is lowered. Storage is for one hour. It is suggested that longer storage is possible, but that has not been proven yet in an existing power plant. However, there are many consideration for using molten salt as an energy storage medium due to the great capability of storing energy for long period of time with some insignificant losses.

Yazd integrated solar combined cycle power station

The Yazd integrated solar combined cycle power station is a hybrid power station situated near Yazd, Iran which became operational in 2009. It is the world's first combined cycle power plant using solar power and natural gas. The plant has a capacity of 467 MWh and uses solar energy to augment its steam generation by concentrating solar power technology. Yazd integrated solar combined cycle power station by the start of 2010 was the eight largest solar power plant in the world.

PS20 Solar Power Tower

The Planta Solar 20 or PS20 solar power tower is a solar thermal energy plant in Sanlucar la Mayor near the southern Spanish city of Seville. It is the world's most powerful solar power tower. The 20 megawatt solar power tower produces electricity with large movable mirrors called heliostats.

Abengoa Solar has begun commercial operation of the giant new PS20 solar power tower located at the Solucar Platform, near Seville. With a generating capacity of 20 megawatts, the new power tower will produce enough solar energy to supply 10,000 homes.

During a three-day production and operational testing period last week, the PS20 surpassed the predicted power output, further validating the high potential of power tower technology, the company said in a statement.

"Generating more power during production testing than the design output is indeed a significant milestone," said Santiago Seage, CEO of Abengoa Solar. "The technological breakthroughs we have achieved, coupled with our cumulative expertise, have enabled us to take a qualitative leap forward in our power tower technology."

The world's second power tower plant in commercial use, PS20 features a number of technological improvements over PS10, Abengoa's and the world's first commercial power tower.

The power capacity of the PS20 is double that of the earlier power tower, and Abengoa Solar has put in a higher-efficiency receiver, improvements in the control and operational systems, and a better thermal energy storage system.

PS20 consists of a solar field made up of 1,255 mirrored heliostats. Each heliostat, with a surface area of 1,291 square feet, reflects the solar radiation it receives onto the receiver, located on the top of a 531 feet-high tower.

The concentrated heat produces steam, which is converted into electricity generation by a turbine.

Abengoa Solar says operation of PS20 will avoid the emission of approximately 12,000 tons of the greenhouse gas carbon dioxide into the atmosphere that a fossil fuel-burning power plant would have produced.

The Solucar platform generates 300 megawatts from a variety of solar sources - 50 MW from tower technology, 250 MW from troughs, 1.2 MW produced by photovoltaic technology, and 80 MW from Stirling dish technology.

Located in Sanlucar la Mayor, the platform will have 300 MW of installed capacity when it is completed in 2013. At that point the company says it is expected to produce enough energy to supply 153,000 households, and will prevent the emission of 185,000 tons of carbon dioxide per year.

During the lifespan of the platform, the company says, it will reduce an estimated four million tons of carbon emissions.

The platform covers a land area of 800 hectares and will create 300 permanent jobs for a total investment of 1.2 billion Euros.

Besides the Solucar Platform, Abengoa Solar is building commercial solar power plants in Spain, Algeria, Morocco and the United States.

With U.S. headquarters in Lakewood, Colorado, last October Abengoa was awarded two research and development projects in the field of concentrating solar power that total over $14 million by the U.S. Department of Energy.

Under the first award, Abengoa aims to develop technology that will reduce the cost of thermal energy storage for parabolic trough-based concentrating solar power systems by 20 to 25 percent. Three other Energy Department contracts were awarded to Abengoa in December 2007 that are focused on developing more efficient parabolic trough technology.

Under the second 2008 contract Abengoa will investigate new technologies for integrating thermal energy storage with power tower systems.

"Thanks to support on both sides of the Atlantic," said Seage, "we will be able to offer energy solutions that are increasingly more clean and efficient."

Extresol Solar Power Station

The Extresol Solar Power Station is a Spanish 150 MW commercial parabolic trough solar thermal power plant, located in Torre de Miguel Sesmero in the province of Badajoz, Spain.

The solar thermal power plant will be formed by three different systems: Extresol 1, Extresol 2 and Extresol 3, of 50 MW each, due to the power limitation of 50 MW per plant established by the Spanish legislation.

Extrasol has a thermal storage system which absorbs part of the heat produced in the solar field during the day and stores it in molten salts.

Extresol 1 costed around 300 M€ and was inagurated the 25th of February 2009.

With EXTRESOL 1 connection, ACS-Cobra becomes the world leader in commercially operating STE (CSP) plants, with a total operating capacity of 150 MW.

As its predecessors ANDASOL 1 and 2, EXTRESOL 1 has a 7.5-hour molten salts storage, which allows a wide dispatchability possibilities to adapt its operation to the grid demand.

ACS-Cobra is presently building another 4 plants with the same basic technology, applying lessons learned in the first projects to improve constructability, performance and/or reduce installation and operation and maintenance costs in these plants.

By 2011, ACS will complete the first set of plants totalling 350 MW of dispatchable power.

ACS, through its 100% subsidiary Cobra, is the EPC contractor in association with SENER of the 17 MW GEMASOLAR central tower project, using molten salts as working and storage fluid with 15-hour capacity, that is presently in advanced construction and will be operational next year.

ACS is actively pursuing, both as shareholder and constructor, projects in the USA, South America, Southern and Eastern Mediterranean countries, Australia, the Gulf countries and China.

Alvarado I

Alvarado I is large solar thermal power plant in Alvarado, in Extremadura, Spain. Construction on the plant commenced in December 2007 and was completed in July 2009, when commercial operations began. With an installed capacity of 50 MWe, it is one of the largest solar thermal power stations in the world.

The facility is built on a 1 km2 (0.4 sq mi) site with a solar resource of 2,174 KW·h/m3/year, producing an estimated 105,200 MW·h of electricity per year (an average power of 12 MW). The plant uses parabolic trough technology, and is made up of 768 solar thermal collectors, with an output temperature of 393 °C (739 °F), transferred with Biphenyl and Diphenyl oxide heat transfer agents.

A second 50 MWe facility, Alvarado II, is currently on the proposal stage. It is planned to be constructed in the same area as Alvarado I.

Alvarado I
Country Spain
Location Alvarado, Extremadura
Coordinates 38°49′37″N 06°49′34″W / 38.82694°N 6.82611°W / 38.82694; -6.82611Coordinates: 38°49′37″N 06°49′34″W / 38.82694°N 6.82611°W / 38.82694; -6.82611
Owner Acciona Energy
Status Operational
Fuel Solar thermal
Installed capacity 50 MWe
Annual generation 105,200 MW·h
Commissioned July 2009

Nevada Solar One

Nevada Solar One is a concentrated solar power plant, with a nominal capacity of 64 MW and maximum capacity of 75 MW. The project required an investment of $266 million USD and electricity production is estimated to be 134 million kilowatt hours per year.

It is the second solar thermal power plant built in the United States in more than 16 years and the largest STE plant built in the world since 1991. It is on the southeast fringes of Boulder City, Nevada and was built in that city's Energy Resource Zone which requires renewable generation as part of plant development permits; Nevada Solar One was approved as part of Duke Energy's larger El Dorado Energy project that built 1 GW of electrical generation capacity. The solar trough generation was built by Acciona Solar Power, a partially owned subsidiary of Spanish conglomerate Acciona Energy. Lauren Engineers & Constructors (Abilene, TX) was the EPC contractor for the project. Acciona purchased a 55 percent stake in Solargenix (formerly Duke Solar) and Acciona owns 95 percent of the project. Nevada Solar One is unrelated to the Solar One power plant in California.

A year earlier, Arizona Public Service's Saguaro Solar Facility opened, in 2006, using similar technology, located 30 miles north of Tucson, and producing 1 MW. Nevada Solar One went online for commercial use on June 27, 2007. It was constructed over a period of 16 months. The total project site is approximately 400 acres (0.6 mi² / 1.6 km²), while the solar collectors cover 300 acres (1.2 km2).

Nevada Solar One uses 760 parabolic troughs (using more than 180,000 mirrors) made by Flabeg AG in Germany that concentrate the sun's rays onto thermos tubes placed at the focal axis of the troughs and containing a heat transfer fluid (solar receivers), in contrast to the power tower concentrator concept that California's original Solar One project uses. These specially coated tubes, made of glass and steel, were designed and produced by Solel Solar Systems as well as by Schott Glass in Germany. Motion control was supplied by Parker Hannifin, from components by Ansco Machine Company. The plant uses 18,240 of these four-meter-long tubes. The heat transfer fluid is heated to 735 °F (391 °C). The heat is then exchanged to water to produce steam which drives a Siemens SST-700 steam turbine, adapted to the specific requirements of the CSP technology.

Solar thermal power plants designed for solar-only generation are well matched to summer noon peak loads in areas with significant cooling demands, such as the southwestern United States. Using thermal energy storage systems, solar thermal operating periods can be extended to meet base load needs. Given Nevada's land and sun resources the state has the ability to produce more than 600 GW using solar thermal concentrators like those used by Nevada Solar One.

Nine parabolic concentrator facilities have been successfully operating in California's Mojave Desert commercially since 1984 with a combined generating capacity of 354MW for these Solar Energy Generating Systems. Other parabolic trough power plants being proposed are two 50 MW plants in Spain (see Solar power in Spain), and two 110 MW plants in Israel.

It has been proposed that massive expansion of solar plants such as Nevada Solar One has the potential to provide sufficient electricity to power the entire United States.

Andasol Solar Power Station

The Andasol solar power station is Europe's first commercial parabolic trough solar thermal power plant, located near Guadix in the province of Granada, Spain.

Andasol Solar Power Station

Andasol Solar Power Station
Country Spain
Location near Guadix,Granada
Coordinates 37°13′42.70″N 3°4′6.73″W / 37.228528°N 3.0685361°W / 37.228528; -3.0685361Coordinates: 37°13′42.70″N 3°4′6.73″W / 37.228528°N 3.0685361°W / 37.228528; -3.0685361
Owner ACS Group (Andasol 1 & 2)
Solar Millennium
MAN Ferrostaal AG
Stadtwerke München
RWE Innogy
Status Operational (Andasol 1 & 2)
Fuel Solar
Installed capacity 50 MW
Commissioned 2009

Andasol is the first parabolic trough solar power plant in Europe, and Andasol 1 went online in March 2009. Because of the high altitude (1,100 m) and the desert climate, the site has exceptionally high annual direct insolation of 2,200 kWh/m² per year. Each plant has a gross electricity output of 50 megawatts (MWe), producing around 180 gigawatt-hours (GW·h) per year (21 MW·yr per year). Each collector has a surface of 51 hectares (equal to 70 soccer fields); it occupies about 200 ha of land.

Andasol has a thermal storage system which absorbs part of the heat produced in the solar field during the day. This heat is then stored in a molten salt mixture of 60% sodium nitrate and 40% potassium nitrate. A turbine produces electricity using this heat during the evening, or when the sky is overcast. This process almost doubles the number of operational hours at the solar thermal power plant per year. A full thermal reservoir holds 1,010 MW·h of heat, enough to run the turbine for about 7.5 hours at full-load, in case it rains or after sunset. The heat reservoirs each consist of two tanks measuring 14 m in height and 36 m in diameter and containing molten salt. Andasol 1 is able to supply environmentally friendly solar electricity for up to 200,000 people.


Andasol 1 cost around €300 million (US$380 million) to build. The developers say Andasol's electricity will cost €0.271 per kilowatt-hour (kW·h) to produce. Thermal energy storage at 400 degrees C (75 tonnes of salt per MWhe) costs roughly US$50 per kilowatt-hour of capacity, according to Greg Glatzmaier of the U.S. National Renewable Energy Laboratory (NREL) — about 5% of Andasol's total cost.

In Spain, solar-thermal electricity receives a feed-in tariff of just under €0.27/kW·h for the next 25 years.

The Andasol solar power plants are helping to meet summer peak electricity demand in the Spanish power grid primarily caused by air conditioning units. The electricity supplied from the Andasol plants is ideal for meeting the demand during the day, particularly early afternoon, when the power demand reaches its peak and solar radiation (as well as the power plant output) are also at their peak.


The developer of the Andasol 1 and Andasol 2 plants are Solar Millennium (25%) and ACS Cobra (75%). After planing, engineering and construction Solar Millennium sold their shares to ACS Group. Andasol 3 is developed by the consortium of Solar Millennium and MAN Ferrostaal. Marquesado Solar SL is the investor consortium which is going to commission and operate Andasol 3. Shareholders of Marquesado Solar SL are:

  • Solanda GmbH, a joint venture of Solar Millennium and MAN Ferrostaal AG (26%)
  • Stadtwerke München (48.9%)
  • RWE Innogy & RheinEnergie (25.1%)

Solar Energy Generating Systems

Solar Energy Generating Systems (SEGS) is the largest solar energy generating facility in the world. It consists of nine solar power plants in California's Mojave Desert, where insolation is among the best available in the United States. SEGS III–VII (150 MW) are located at Kramer Junction, SEGS VIII–IX (160 MW) at Harper Lake, and SEGS I–II (44 MW) at Daggett respectively. NextEra Energy Resources operates and partially owns the plants located at Kramer Junction and Harper Lake.

Plants' scale and operations

The plants have a 354 MW installed capacity, making it the largest installation of solar plants of any kind in the world. The average gross solar output for all nine plants at SEGS is around 75 MWe — a capacity factor of 21%. In addition, the turbines can be utilized at night by burning natural gas.

NextEra claims that the solar plants power 232,500 homes and displace 3,800 tons of pollution per year that would have been produced if the electricity had been provided by fossil fuels, such as oil.

The facilities have a total of 936,384 mirrors and cover more than 1,600 acres (6.5 km2). Lined up, the parabolic mirrors would extend over 229 miles (370 km).

Principle of operation

The installation uses parabolic trough solar thermal technology along with natural gas to generate electricity. 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.


The parabolic mirrors are shaped like a half-pipe. 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 3000 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.

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, 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, and commissioned between 1984 and 1991. Kramer Junction employs about 95 people and 45 people work at Harper Lake.

SEGS plant history and operational data
Plant Year
Location Net turbine
Gross solar production
of electricity (MWh)

(MW) (m²) (°C) 1996 average 1998–2002
SEGS I 1984 Daggett 14 82,960 307 19,900 16,500
SEGS II 1985 Daggett 30 165,376 316 36,000 32,500
SEGS III 1986 Kramer Jct. 30 230,300 349 64,170 68,555
SEGS IV 1986 Kramer Jct. 30 230,300 349 61,970 68,278
SEGS V 1987 Kramer Jct. 30 233,120 349 71,439 72,879
SEGS VI 1988 Kramer Jct. 30 188,000 391 71,409 67,758
SEGS VII 1988 Kramer Jct. 30 194,280 391 70,138 65,048
SEGS VIII 1989 Harper Lake 80 464,340 391 139,174 137,990
SEGS IX 1990 Harper Lake 80 483,960
141,916 125,036

Harper Lake

SEGS VIII and SEGS IX, located at 35°01′54″N 117°20′53″W / 35.0316°N 117.348°W / 35.0316; -117.348 (SEGS VIII and IX), are the largest solar power plants individually and collectively in the world. 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. SEGS VIII and IX have operated continuously and have been commercially successful since the very beginning.

Kramer Junction

This location (35°00′51″N 117°33′32″W / 35.0142°N 117.559°W / 35.0142; -117.559 (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), one of the best in the nation.


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).

Accidents and incidents

In February 1999, a 900,000-US-gallon (3,400 m3) therminol storage tank exploded at the SEGS II (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 caustic soda. The immediate area of 0.5 square miles (1.3 km2) was evacuated.