Solar thermal energy (STE) is a form of energy and a technology for harnessing solar energy to generate thermal energy for use in industry, and in the residential and commercial sectors. Solar thermal collectors are classified by the United States Energy Information Administration as low-, medium-, or high-temperature collectors. Low-temperature collectors are generally unglazed and used to heat swimming pools or to heat ventilation air. Medium-temperature collectors are also usually flat plates but are used for heating water or air for residential and commercial use.
There are several solar power plants in the Mojave Desert which supply power to the electricity grid. Insolation in the Mojave Desert is among the best available in the United States, and some significant population centers are located in the area. These plants can generally be built in a few years because solar plants are built almost entirely with modular, readily available materials. Solar Energy Generating Systems (SEGS) is the name given to nine solar power plants in the Mojave Desert which were built in the 1980s, the first commercial solar plant. These plants have a combined capacity of 354 megawatts (MW) which made them the largest solar power installation in the world, until Ivanpah Solar Power Facility was finished in 2014.
Spain is one of the first countries to deploy large-scale solar photovoltaics, and is the world leader in concentrated solar power (CSP) production.
Solar power includes solar farms as well as local distributed generation, mostly on rooftops and increasingly from community solar arrays. In 2023, utility-scale solar power generated 164.5 terawatt-hours (TWh), or 3.9% of electricity in the United States. Total solar generation that year, including estimated small-scale photovoltaic generation, was 238 TWh.
The Solana Generating Station is a solar power plant near Gila Bend, Arizona, about 70 miles (110 km) southwest of Phoenix. It was completed in 2013. When commissioned, it was the largest parabolic trough plant in the world, and the first U.S. solar plant with molten salt thermal energy storage. Built by the Spanish company Abengoa Solar, the project can produce up to 280 megawatts (MW) gross, supplied by two 140 MW gross (125 MW net) steam turbine generators: enough electricity to meet the needs of approximately 70,000 homes and obviate the emission of roughly 475,000 tons of CO2 every year. Its name is the Spanish term for "sunny spot".
Concentrated solar power systems generate solar power by using mirrors or lenses to concentrate a large area of sunlight into a receiver. Electricity is generated when the concentrated light is converted to heat, which drives a heat engine connected to an electrical power generator or powers a thermochemical reaction.
BrightSource Energy, Inc. is an Oakland, California based, corporation that designs, builds, finances, and operates utility-scale solar power plants. Greentech Media ranked BrightSource as one of the top 10 greentech startups in the world in 2008.
A solar power tower, also known as 'central tower' power plant or 'heliostat' power plant, is a type of solar furnace using a tower to receive focused sunlight. It uses an array of flat, movable mirrors to focus the sun's rays upon a collector tower. Concentrating Solar Power (CSP) systems are seen as one viable solution for renewable, pollution-free energy.
SolarReserve was a developer of utility-scale solar power projects which include Concentrated Solar Power (CSP) and Photovoltaic (PV) technology. The company has commercialized solar thermal energy storage technology that enables solar power tower CSP plants to deliver electricity day and night. In this technology, a molten salt is used to capture the energy from the sun and store it. When electricity is needed, the stored liquid salt is used to turn water into steam to turn a turbine and generate electricity.
The use of solar energy began in Israel in the 1950s with the development by Levi Yissar of a solar water heater to address the energy shortages that plagued the new country. By 1967 around 5% of water of households were solar heated and 50,000 solar heaters had been sold. With the 1970s oil crisis, Harry Zvi Tabor developed the prototype of the solar water heater now used in over 90% of Israeli homes. There are over 1.3 million solar water heaters installed as a result of mandatory solar water heating regulations.
Solar power in Nevada is growing due to a Renewable Portfolio Standard which requires 50% renewable energy by 2030. The state has abundant open land areas and some of the best solar potential in the country.
Solar power in New Mexico in 2016 generated 2.8% of the state's total electricity consumption, despite a National Renewable Energy Laboratory (NREL) projection suggesting a potential contribution three orders of magnitude larger.
Solar power in South Africa includes photovoltaics (PV) as well as concentrated solar power (CSP). As of July 2024, South Africa had 2,287 MW of installed utility-scale PV solar power capacity in its grid, in addition to 5,791 MW of rooftop solar and 500 MW of CSP. Installed capacity is expected to reach 8,400 MW by 2030.
Solar power in Morocco is enabled by the country having one of the highest rates of solar insolation among other countries— about 3,000 hours per year of sunshine but up to 3,600 hours in the desert. Morocco has launched one of the world’s largest solar energy projects costing an estimated $9 billion. The aim of the project was to create 2,000 megawatts of solar generation capacity by 2020. The Moroccan Agency for Solar Energy (MASEN), a public-private venture, was established to lead the project. The first plant, Ouarzazate Solar Power Station, was commissioned in 2016.
Khi Solar One (KSO) is a solar power tower solar thermal power plant, located in the Northern Cape Region of South Africa. Khi Solar One is 50 megawatts (MW), and is the first solar tower plant in Africa. It covers an area of 140 hectares.
Cerro Dominador Solar Power Plant is a 210-megawatt (MW) combined concentrated solar power and photovoltaic plant located in the commune of María Elena in the Antofagasta Region of Chile, about 24 kilometres west-northwest of Sierra Gorda. The project was approved by the Chilean government in 2013 and construction was started by Abengoa Solar Chile, a branch of the multinational Abengoa Spain. The plant was inaugurated on June 8, 2021. A follow-up project called Likana Solar bid $33.99/MWh in an auction in August 2021.
While being a major oil producing country, the United Arab Emirates (UAE) has taken steps to introduce solar power on a large scale. However, solar power still accounts for a small share of energy production in the country. The country was the 6th top carbon dioxide emitter per capita in the world in 2009, with 40.31 tonnes, but is planning to generate half of its electrical energy by 2050 from solar and nuclear sources, targeting 44% renewables, 38% gas, 12% coal, and 6% nuclear energy sources.
Mohammed bin Rashid Al Maktoum Solar Park is a solar park spread over a total area of 77 km2 (30 sq mi) in Saih Al-Dahal, about 50 km (31 mi) south of the city of Dubai in the United Arab Emirates (UAE).
Redstone Solar Thermal Power (RSTP) is a solar power tower with molten salt energy storage, located in Postmasburg, near Kimberley, in the Northern Cape Region of South Africa. Redstone will have a capacity of 100 megawatts (MW) to deliver power to 200,000 people and was awarded in bid window 3.5 of the REIPPP at a strike price of 122.3 ZAR/KWh including time of day pricing in 2015. The project was initially based on the technology of now bankrupt Solar Reserve, but was delayed for several years because the PPA was not signed by Eskom until 2018. After the project was revived the plant is now under construction and the technology will be provided by Brightsource and John Cockerill, as demonstrated in the Noor Energy 1 project in the UAE.
