Solar energy is radiant light and heat from the Sun that is harnessed using a range of technologies such as solar power to generate electricity, solar thermal energy, and solar architecture. It is an essential source of renewable energy, and its technologies are broadly characterized as either passive solar or active solar depending on how they capture and distribute solar energy or convert it into solar power. Active solar techniques include the use of photovoltaic systems, concentrated solar power, and solar water heating to harness the energy. Passive solar techniques include orienting a building to the Sun, selecting materials with favorable thermal mass or light-dispersing properties, and designing spaces that naturally circulate air.
A solar furnace is a structure that uses concentrated solar power to produce high temperatures, usually for industry. Parabolic mirrors or heliostats concentrate light (Insolation) onto a focal point. The temperature at the focal point may reach 3,500 °C (6,330 °F), and this heat can be used to generate electricity, melt steel, make hydrogen fuel or nanomaterials.
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.
A solar thermal collector collects heat by absorbing sunlight. The term "solar collector" commonly refers to a device for solar hot water heating, but may refer to large power generating installations such as solar parabolic troughs and solar towers or non water heating devices such as solar cooker, solar air heaters.
A parabolic trough is a type of solar thermal collector that is straight in one dimension and curved as a parabola in the other two, lined with a polished metal mirror. The sunlight which enters the mirror parallel to its plane of symmetry is focused along the focal line, where objects are positioned that are intended to be heated. In a solar cooker, for example, food is placed at the focal line of a trough, which is cooked when the trough is aimed so the Sun is in its plane of symmetry.
A heliostat is a device that includes a mirror, usually a plane mirror, which turns so as to keep reflecting sunlight toward a predetermined target, compensating for the Sun's apparent motions in the sky.
A solar cooker is a device which uses the energy of direct sunlight to heat, cook or pasteurize drink and other food materials. Many solar cookers currently in use are relatively inexpensive, low-tech devices, although some are as powerful or as expensive as traditional stoves, and advanced, large scale solar cookers can cook for hundreds of people. Because they use no fuel and cost nothing to operate, many nonprofit organizations are promoting their use worldwide in order to help reduce fuel costs and air pollution, and to help slow down deforestation and desertification.
The SOLAR Project consists of the Solar One, Solar Two and Solar Tres solar thermal power plants based in the Mojave Desert, United States and Andalucía, Spain. The US Department of Energy (DOE) and a consortium of US utilities built the country's first two large-scale, demonstration solar power towers in the desert near Barstow, California.
The THEMIS solar power tower is a research and development centre focused on solar energy. It is located near the village of Targasonne, in the department of Pyrénées-Orientales, south of France, 3 kilometres from the world's largest solar furnace in Odeillo.
Solar air conditioning, or "solar-powered air conditioning", refers to any air conditioning (cooling) system that uses solar power.
The PS10 Solar Power Plant, is the world's first commercial concentrating solar power tower operating near Seville, in Andalusia, Spain. 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 has cost €35 million (US$46 million). PS10 produces about 23,400 megawatt-hours (MW·h) per year, for which it receives €271 (US$360) per MW·h under its power purchase agreement, equating to a revenue of €6.3 million per year.
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.
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.
A compact linear Fresnel reflector (CLFR) – also referred to as a concentrating linear Fresnel reflector – is a specific type of linear Fresnel reflector (LFR) technology. They are named for their similarity to a Fresnel lens, in which many small, thin lens fragments are combined to simulate a much thicker simple lens. These mirrors are capable of concentrating the sun's energy to approximately 30 times its normal intensity.
Leonard "Lynn" L. Northrup Jr. was an American engineer who was a pioneer of the commercialization of solar thermal energy. Influenced by the work of John Yellott, Maria Telkes, and Harry Tabor, Northrup's company designed, patented, developed and manufactured some of the first commercial solar water heaters, solar concentrators, solar-powered air conditioning systems, solar power towers and photovoltaic thermal hybrid systems in the United States. The company he founded became part of ARCO Solar, which in turn became BP Solar, which became the largest solar energy company in the world. Northrup was a prolific inventor with 14 US patents.
Concentrator photovoltaics (CPV) is a photovoltaic technology that generates electricity from sunlight. Unlike conventional photovoltaic systems, it uses lenses or curved mirrors to focus sunlight onto small, highly efficient, multi-junction (MJ) solar cells. In addition, CPV systems often use solar trackers and sometimes a cooling system to further increase their efficiency.
The following outline is provided as an overview of and topical guide to solar energy:
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.
Ouarzazate Solar Power Station (OSPS), also called Noor Power Station is a solar power complex and auxiliary diesel fuel system located in the Drâa-Tafilalet region in Morocco, 10 kilometres (6.2 mi) from Ouarzazate town, in Ghessat rural council area. At 510 MW, it is the world's largest concentrated solar power (CSP) plant. With an additional 72 MW photovoltaic system the entire project was planned to produce 582 MW. The total project's estimated cost is around $9 billion.
The Odeillo solar furnace is the world's largest solar furnace. It is situated in Font-Romeu-Odeillo-Via, in the department of Pyrénées-Orientales, in the south of France. It is 48 metres (157 ft) high and 54 metres (177 ft) wide, and includes 63 heliostats. It was built between 1962 and 1968, started operating in 1969, and has a power of one megawatt.
