Sierra SunTower was a 5 MW commercial

concentrating solar power Concentrated solar power (CSP, also known as concentrating solar power, concentrated solar thermal) systems generate solar power by using mirrors or lenses to concentrate a large area of sunlight into a receiver. Electricity is generated when ...

(CSP) plant built and operated by

eSolar eSolar is a privately held company that develops concentrating solar power (CSP) plant technology. The company was founded by the Pasadena-based business incubator Idealab in 2007 as a developer of CSP plant technology. The company aims to devel ...

. The plant is located in

Lancaster, California Lancaster is a charter city in northern Los Angeles County, in the Antelope Valley of the western Mojave Desert in Southern California. As of the 2020 census, the population was 173,516, making Lancaster the 153rd largest city in the United ...

. As of mid-September, 2022, the two towers that were the center of the facility are no longer standing. However the rest of the plant is still present.

Project overview

The Sierra SunTower facility was based on power tower CSP technology. The plant featured an array of heliostats which reflected solar radiation to a tower-mounted thermal receiver. The concentrated solar energy boiled water in the receiver to produce steam. The steam was piped to a turbine generator which converted the energy to electricity. The steam coming out of the turbine was condensed and pressurized back into the receiver. In the summer of 2009,

unveiled the 5 MW Sierra SunTower plant, a commercial facility in

, to demonstrate the efficacy of this CSP technology. Sierra SunTower was connected to the

Southern California Edison Southern California Edison (or SCE Corp), the largest subsidiary of Edison International, is the primary electricity supply company for much of Southern California. It provides 15 million people with electricity across a service territory of ap ...

(SCE) grid and, in spring 2010, it was the only commercial CSP tower facility in North America. The project site occupied approximately in an arid valley in the southwestern corner of the

Mojave Desert The Mojave Desert ( ; mov, Hayikwiir Mat'aar; es, Desierto de Mojave) is a desert in the rain shadow of the Sierra Nevada mountains in the Southwestern United States. It is named for the indigenous Mojave people. It is located primarily ...

at 35° north latitude, on private farm land.Mernit, Judith Lewis
A solar plant a tortoise could love
''High Country News'', 10 August 2009. Accessed: 9 January 2011. Sierra SunTower included two modules. 24,000 heliostats, divided between four sub-fields, tracked the sun and focused its energy onto two tower-mounted receivers. The focused heat converted feedwater piped to the receivers into superheated steam that drove a reconditioned 1947 GE turbine generator to produce electricity. The steam passed through a steam condenser, reverted to water through cooling, and the process repeated. Sierra SunTower Site

During the 12 months of construction, Sierra SunTower created over 300 temporary jobs. During operation, the site employed 21 permanent employees. At 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 was certified by the

California Energy Commission The California Energy Commission, formally the Energy Resources Conservation and Development Commission, is the primary energy policy and planning agency for California. Created in 1974 and headquartered in Sacramento, the Commission'core respon ...

as a renewable energy facility. Power from the facility was sold under a

Power Purchase Agreement A power purchase agreement (PPA), or electricity power agreement, is a contract between two parties, one which generates electricity (the seller) and one which is looking to purchase electricity (the buyer). The PPA defines all of the commercial te ...

(PPA) with

SCE SCE is an abbreviation with multiple meanings: Science * Short-channel effect, a secondary effect describing the reduction in threshold voltage Vth in MOSFETs with non-uniformly doped channel regions as the gate length increases * Saturated calomel ...

, with a projected maximum output sufficient to power approximately 4,000 homes. The 5 MW output from Sierra SunTower displaced emissions by 7,000 tons per year, an amount equivalent to planting of trees, removing 1,368 automobiles from the road, or saving 650,000 gallons of gasoline. Sierra SunTower was designed to validate eSolar's technology at full scale, effectively eliminating scaleup risks, and to serve as a model from which future plants of this type would be built. However, in 2015, the Sierra SunTower was shut down for commercial operation, as it was deemed to be too costly to operate except on the sunniest of days. Thus, it served to show the real-world problems, and unpredictable nature, of concentrated solar power.

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 distinguished 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 recognized eSolar's achievements in the clean energy industry by naming Sierra SunTower an exceptional breakthrough in the commercialization of solar thermal technology.

Performance data from US Treasury Dept.

According to US Treasury Department - Performance Report and Certification Form, the eSolar Sierra SunTower generated 539 MWh (MegaWatt-hour) of electricity from August 1, 2010, to July 31, 2011. A total of 539 MWh of gross electrical energy was generated at Sierra during the period Aug 1, 2010 and July 31, 2011. This was approximately 12.6% of the expected power generation of the initial estimate of 4270 MWh.

Production

References

External links