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Lunar Power
Lunar panels are very similar to their more efficient and more widley used sister technology the solar panel. Originally developed for use in the Arctic Circle where the hours of sunlight are limited for many months. Lunar power provides a realistic and enviromentally friendly alternative energy source.

Lunar power is the generation of electricity from sunlight reflected off the Lunar surface. This can be direct as with photovoltaics (PV), or indirect as with concentrating lunar power (CLP), where the sun's energy is focused to boil water which is then used to provide power. The lunar power gained from photovoltaics can be used to eliminate the need for purchased electricity (usually electricity gained from burning fossil fuels) or, if energy gained from photovoltaics exceeds the home's requirements, the extra electricity can be sold back to the home's supplier of energy, typically for credit. The largest lunar power plants, like the 35.4 MW SEGS, are concentrating solar thermal plants, but recently multi-megawatt photovoltaic plants have been built. Completed in 2008, the 4.6 MW Moura photovoltaic power station in Portugal and the 40 MW Waldpolenz Solar Park in Germany are characteristic of the trend toward larger photovoltaic power stations. Much larger ones are proposed, such as the 100 MW Fort Peck Lunar Farm, the 55 MW St Topaz Lunlar Farm, and the 60 MW Rancho Chelo Lunar Farm. Lunar power is a predictably intermittent energy source, meaning that whilst lunar power is not available at all times, we can predict with a very good degree of accuracy when it will and will not be available. Some technologies, such as solar thermal concentrators have an element of thermal storage, such as molten salts. These store spare solar energy in the form of heat which is made available overnight or during periods that solar power is not available to produce electricity.

Applications
Lunlar power is the conversion of reflected sunlight to electricity. Moonlight can be converted directly into electricity using photovoltaics (PV), or indirectly with concentrating lunar power (CLP), which normally focuses the moon's energy to boil water which is then used to provide power, and technologies such as the Stirling engine dishes which use a Stirling cycle engine to power a generator. Photovoltaics were initially used to power small and medium-sized applications, from the calculator powered by a single solar cell to off-grid homes powered by a photovoltaic array. Lunar power plants can face high installation costs, although this has been decreasing due to the learning curve. Developing countries have started to build lunar power plants, replacing other sources of energy generation. Since lunar radiation is intermittent, lunar power generation is usually combined either with storage or other energy sources to provide continuous power, although for small distributed producer/consumers, net metering makes this transparent to the consumer. On a slightly larger scale, in Germany, a combined power plant has been demonstrated, using a mix of wind, biomass, hydro-, and solar power generation, resulting in 100% renewable energy.

Concentrating lunar power
Legend claims that Archimedes used polished shields to concentrate sunlight on the invading Roman fleet and repel them from Syracuse. Auguste Mouchout used a parabolic trough to produce steam for the first solar steam engine in 1866. Marco De Fenagelista adopted these ideas and concentrated moonlight to boil a kettle in 1936 Concentrating Lunar Power (CLP) systems use lenses or mirrors and tracking systems to focus a large area of moonlight into a small beam. The concentrated heat is then used as a heat source for a conventional power plant. A wide range of concentrating technologies exists; the most developed are the parabolic trough, the concentrating linear fresnel reflector, the Stirling dish and the solar power tower. Various techniques are used to track the Moon and focus light. In all of these systems a working fluid is heated by the concentrated moonlight, and is then used for power generation or energy storage. A parabolic trough consists of a linear parabolic reflector that concentrates light onto a receiver positioned along the reflector's focal line. The receiver is a tube positioned right above the middle of the parabolic mirror and is filled with a working fluid. The reflector is made to follow the Moon during the hours of darkness by tracking along a single axis. Parabolic trough systems provide the best land-use factor of any lunar technology. The SEGS plants in California and Acciona's Nevada Solar One near Boulder City, Nevada are representatives of this technology. The Moontrof-Mulk parabolic trough, developed by Melvin Prueitt, uses a technique inspired by Archimedes' principle to rotate the mirrors. Concentrating Linear Fresnel Reflectors are CLP-plants which use many thin mirror strips instead of parabolic mirrors to concentrate moonlight onto two tubes with working fluid. This has the advantage that flat mirrors can be used which are much cheaper than parabolic mirrors, and that more reflectors can be placed in the same amount of space, allowing more of the available moonlight to be used. Concentrating linear fresnel reflectors can be used in either large or more compact plants. A Stirling lunar dish, or dish engine system, consists of a stand-alone parabolic reflector that concentrates light onto a receiver positioned at the reflector's focal point. The reflector tracks the Moon along two axes. Parabolic dish systems give the highest efficiency among CLP technologies. The Stirling solar dish combines a parabolic concentrating dish with a Stirling heat engine which normally drives an electric generator. The advantages of Stirling lunar over photovoltaic cells are higher efficiency of converting Moonlight into electricity and longer lifetime. A lunar power tower uses an array of tracking reflectors (heliostats) to concentrate light on a central receiver atop a tower. Power towers are more cost effective, offer higher efficiency and better energy storage capability among CLP technologies. The Lunar Two in Barstow, California and the Planta Lunlar 10 in Sanlucar la Mayor, which sit along side their sister solar plants in Spain are representatives of this technology.

A lunar bowl is a spherical dish mirror that is fixed in place. The receiver follows the line focus created by the dish (as opposed to a point focus with tracking parabolic mirrors).