Heat and light from the sun fuel life on earth.

The total solar energy available to the earth is approximately 3850 zettajoules (ZJ) per year (89,000 TW).

Solar power (also known as solar energy) is a source of power that uses energy from the sun. The term solar energy is used more specifically to describe the utilization of this energy through human endeavor. It is a renewable energy source that has been used in many traditional technologies for centuries. It is also in widespread use where other power supplies are absent, such as in remote locations and in space. The primary forms of solar energy are heat and light. Secondary forms and effects include photosynthesis, wind, the Gulf Stream, the hydrologic cycle, fossil fuels and electricity. Image File history File links Sun920607. ... Image File history File links Sun920607. ... Image File history File linksMetadata Download high-resolution version (1067x702, 84 KB) Author: Frank van Mierlo Graphic representation of the available energy flux vs energy consumption. ... Image File history File linksMetadata Download high-resolution version (1067x702, 84 KB) Author: Frank van Mierlo Graphic representation of the available energy flux vs energy consumption. ... The joule (IPA: or ) (symbol: J) is the SI unit of energy. ... Renewable energy utilizes natural resources such as sunlight, wind, tides and geothermal heat, which are naturally replenished. ... For articles on specific fuels used in vehicles, see Biogas, Bioethanol, Biobutanol, Biodiesel, and Straight vegetable oil. ... See biomass (ecology) for the use of the term in ecology, where it refers to the cumulation of living matter Switchgrass, a tough plant used in the biofuel industry in the United States Rice chaff. ... Krafla Geothermal Station in northeast Iceland Geothermal power is energy generated by heat stored beneath the Earths surface. ... Hydroelectricity is electricity produced by hydropower. ... Tidal power, sometimes called tidal energy, is a form of hydropower that exploits the rise and fall in sea levels due to the tides, or the movement of water caused by tidal currents. ... Wave power refers to the energy of ocean surface waves and the capture of that energy to do useful work - including electricity generation, desalination, and the pumping of water (into reservoirs). ... An example of a wind turbine. ... Sol redirects here. ... Renewable energy utilizes natural resources such as sunlight, wind, tides and geothermal heat, which are naturally replenished. ... Layers of Atmosphere - not to scale (NOAA)[1] Outer space, sometimes simply called space, refers to the relatively empty regions of the universe outside the atmospheres of celestial bodies. ... The leaf is the primary site of photosynthesis in plants. ... For the album by Ocean Colour Scene, see North Atlantic Drift (album) The Gulf Stream is orange and yellow in this representation of water temperatures of the Atlantic. ... The water cycle—technically known as the hydrologic cycle—is the circulation of water within the earths hydrosphere, involving changes in the physical state of water between liquid, solid, and gas phases. ... Fossil fuels are hydrocarbons, primarily coal and petroleum (fuel oil or natural gas), formed from the fossilized remains of dead plants and animals[1] by exposure to heat and pressure in the Earths crust over hundreds of millions of years[2]. The theory that hydrocarbons were formed from these... For other uses, see Electricity (disambiguation). ...

Solar energy also broadly describes technologies that utilize sunlight. The applications are diverse and date back millennia. The Greeks, Native Americans and Chinese warmed their buildings by orienting them toward the sun. European farmers used elaborate field orientation and thermal mass to increase crop yields during the Little Ice Age. Modern solar technologies continue to harness the sun to provide water heating, daylighting and even flight.^[1] By the mid 20th century humans had achieved a mastery of technology sufficient to leave the surface of the Earth for the first time and explore space. ... Cliff Palace, Mesa Verde National Park White House Ruins, Canyon de Chelly National Monument Ancient Pueblo People or Ancestral Puebloans were a prehistoric Native American culture centered around the present-day Four Corners area of the Southwest United States, noted for their distinctive pottery and dwelling construction styles. ... Thermal mass, in the most general sense, is any mass that absorbs and holds heat. ... The Little Ice Age (LIA) was a period of cooling occurring after a warmer era known as the Medieval climate optimum. ...

The term solar power specifically describes technologies that convert sunlight into electricity or mechanical power. In 1866, the French engineer Auguste Mouchout successfully powered a steam engine with sunlight. This is the first known example of a solar powered mechanical device. Over the next 50 years inventors such as John Ericsson, Charles Tellier and Frank Shuman developed solar powered devices for irrigation, refrigeration and locomotion. The progeny of these early developments are concentrating solar power plants. Auguste Mouchout was a 19th century French inventor of the earliest solar-powered engine, converting solar energy into mechanical steam power. ... John Ericsson (1803-1889) This article is about John Ericsson, the Swedish and American inventor. ...

In 1954, researchers at Bell Laboratories developed a solar cell capable of converting light into electricity via the photovoltaic effect. This breakthrough marked a fundamental change in how power is generated. Since then solar cells have progressed from early cells priced at $1500 per watt to modern cells which can cost less than $3 per watt.

The utilization of solar energy spans from traditional technologies that provide food, heat and light to electricity which is uniquely modern. The diversity of form and long history of solar energy are manifest in a wide variety of applications. These include:

• Heat (hot water, building heat, cooking, process heat)
• Lighting (daylighting, hybrid lighting, daylight savings time)
• Electricity generation (photovoltaics, heat engines)
• Transportation (solar car, solar plane, solar boat)
• Desalination
• Biomass (wood, biofuel)
• Clothes drying

For other uses, see Heat (disambiguation) In physics, heat, symbolized by Q, is energy transferred from one body or system to another due to a difference in temperature. ... A trio of propane water heaters. ... HVAC may also stand for High-voltage alternating current HVAC systems use ventilation air ducts installed throughout a building that supply conditioned air to a room through rectangular or round outlet vents, called diffusers; and ducts that remove air from return-air grilles Fire-resistance rated mechanical shaft with HVAC... Cooking is the act of preparing food. ... Daylighting is the practice of placing windows, or other transparent media, and reflective surfaces so that, during the day, natural light provides effective internal illumination. ... For other uses, see Electricity (disambiguation). ... Photovoltaic tree in Styria, Austria Photovoltaics, or PV for short, is a solar power technology that uses solar cells or solar photovoltaic arrays to convert light from the sun directly into electricity. ... A heat engine performs the conversion of heat energy to work by exploiting the temperature gradient between a hot source and a cold sink. Heat is transferred to the sink from the source, and in this process some of the heat is converted into work. ... The winners of the 2003 American Solar Challenge A solar car is an electric vehicle powered by solar energy obtained from solar panels on the surface of the car. ... Shevchenko BN350 desalination unit situated on the shore of the Caspian Sea. ... See biomass (ecology) for the use of the term in ecology, where it refers to the cumulation of living matter Switchgrass, a tough plant used in the biofuel industry in the United States Rice chaff. ... Clothes pins on a clothes line Clothes line is any type of string, rope, cord, or twine that has been stretched between two points, generally outside, a few feet above the ground. ...

Energy from the Sun

Solar power as it is dispersed on the planet and radiated back to space. Values are in PW =10¹⁵ W

Annual average insolation at the top of Earth's atmosphere (top) and at the surface (bottom). The black dots represent the land area required to replace the total primary energy supply with electricity from solar cells.^[2]

The Earth receives 174 petawatts (PW) of solar radiation at the upper atmosphere. While traveling through the atmosphere, 6% of the incoming solar radiation (insolation) is reflected and 16% is absorbed.^[3] Average atmospheric conditions (clouds, dust, pollutants) further reduce insolation by 20% through reflection and 3% through absorption.^[4] The absorption of solar energy by atmospheric convection (sensible heat transport) and by the evaporation and condensation of water vapor (latent heat transport) drive the winds and the water cycle. Image File history File linksMetadata Download high-resolution version (973x706, 214 KB) Graphic is original and mine, it was however heavily inspired by the work of others. ... Image File history File linksMetadata Download high-resolution version (973x706, 214 KB) Graphic is original and mine, it was however heavily inspired by the work of others. ... (Redirected from 1 E15) This list compares various sizes of positive numbers, including counts of things, dimensionless numbers and probabilities. ... Image File history File links Size of this preview: 645 × 599 pixelsFull resolution (732 × 680 pixel, file size: 24 KB, MIME type: image/png)Original work (Insolation. ... Image File history File links Size of this preview: 645 × 599 pixelsFull resolution (732 × 680 pixel, file size: 24 KB, MIME type: image/png)Original work (Insolation. ... Not to be confused with insulation. ... This article is about Earth as a planet. ... A solar cell, a form of photovoltaic cell, is a device that uses the photoelectric effect to generate electricity from light, thus generating solar power (energy). ... This article describes the SI prefix peta. ... For other uses, see Watt (disambiguation). ... Solar irradiance spectrum at top of atmosphere. ... “Air” redirects here. ... Not to be confused with insulation. ... The reflection of a bridge in Indianapolis, Indianas Central Canal. ... In physics, absorption is the process by which the energy of a photon is taken up by another entity, for example, by an atom whose valence electrons make a transition between two electronic energy levels. ... hello--~~~~fake <gallery> poos[[kill]] </gallery> For other uses, see Cloud (disambiguation). ... Look up dust in Wiktionary, the free dictionary. ... Many of the compounds which are dangerous to the environment can also be harmful to humans in the long-term range and come from mineral and fossil sources or are produced by humans themselves. ... For the 1928 film, see The Wind. ... The movement of water around, over, and through the Earth is called the water cycle. ...

Atmospheric conditions not only reduce the quantity of insolation reaching the Earth's surface but also affect the quality of insolation by diffusing approximately 20% of the incoming light and altering its spectrum. After passing through the Earth's atmosphere approximately half the insolation is in the visible electromagnetic spectrum with the other half mostly in the infrared and ultraviolet spectrum.^[5][6] Diffuse insolation is the solar radiation that is scattered or reflected by atmospheric components (clouds, for example) to the earths surface. ... In most modern usages of the word spectrum, there is a unifying theme of between extremes at either end. ... The optical spectrum (light or visible spectrum) is the portion of the electromagnetic spectrum that is visible to the human eye. ... Legend γ = Gamma rays HX = Hard X-rays SX = Soft X-Rays EUV = Extreme ultraviolet NUV = Near ultraviolet Visible light NIR = Near infrared MIR = Moderate infrared FIR = Far infrared Radio waves EHF = Extremely high frequency (Microwaves) SHF = Super high frequency (Microwaves) UHF = Ultra high frequency VHF = Very high frequency HF = High... For other uses, see Infrared (disambiguation). ...

Upon reaching the surface, insolation is absorbed by the oceans, earth and plants. The energy captured in the oceans drives the thermohaline cycle. As such, solar energy is ultimately responsible for temperature driven ocean currents such as the thermohaline cycle and wind driven currents such as the Gulf Stream. The energy absorbed by the earth in conjunction with that recycled by the Greenhouse effect warms the surface to an average temperature of approximately 33°C.^[7] The solar energy captured by plants and other phototrophs is converted to chemical energy via photosynthesis. All the food we eat, wood we build with and fossil fuels we use are products of photosynthesis.^[8] A simplified summary of the path of the Thermohaline Circulation. ... An ocean current is any more or less permanent or continuous, directed movement of ocean water that flows in one of the Earths oceans. ... For the album by Ocean Colour Scene, see North Atlantic Drift (album) The Gulf Stream is orange and yellow in this representation of water temperatures of the Atlantic. ... A schematic representation of the exchanges of energy between outer space, the Earths atmosphere, and the Earth surface. ... Phototrophs or photoautotrophs are photosynthetic algae, fungi, bacteria and cyanobacteria which build up carbon dioxide and water into organic cell materials using energy from sunlight. ... The leaf is the primary site of photosynthesis in plants. ...

The flows and stores of solar energy are very large relative to human needs.

• The total solar energy available to the earth is approximately 3850 zettajoules (ZJ) per year.^[9]
• Oceans absorb approximately 285 ZJ of solar energy per year.^[10]
• Winds can theoretically supply 6 ZJ of energy per year.^[11]
• Biomass captures approximately 1.8 ZJ of solar energy per year.^[12][13]
• Worldwide energy consumption was 0.471 ZJ in 2004.^[14]

The map on the right (top) shows how solar radiation at the top of the earth's atmosphere varies with latitude. The bottom map shows annual average ground level insolation. For example, in North America the average insolation at ground level over an entire year (including nights and periods of cloudy weather) lies between 125 and 375 W/m² (3 to 9 kWh/m²/day).^[15] At present, photovoltaic panels typically convert about 15% of incident sunlight into electricity; therefore, a solar panel in the contiguous United States on average delivers 19 to 56 W/m² or 0.45 - 1.35 kWh/m²/day.^[16] Zetta (symbol Z) is a SI prefix in the SI system of units denoting 1021 or 1 000 000 000 000 000 000 000. ... The joule (IPA: or ) (symbol: J) is the SI unit of energy. ... Animated map exhibiting the worlds oceanic waters. ... Bold text For other uses, see Wind (disambiguation). ... See biomass (ecology) for the use of the term in ecology, where it refers to the cumulation of living matter Switchgrass, a tough plant used in the biofuel industry in the United States Rice chaff. ... Solar irradiance spectrum at top of atmosphere. ... This article is about the geographical term. ... North America North America is a continent[1] in the Earths northern hemisphere and (chiefly) western hemisphere. ... A solar cell, a form of photovoltaic cell, is a device that uses the photoelectric effect to generate electricity from light, thus generating solar power (energy). ...

Types of technologies

Many technologies use solar energy. Some classifications of solar technology are active, passive, direct and indirect.

• Active solar systems use electrical and mechanical components such as tracking mechanisms, pumps and fans to process sunlight into usable outputs such as heating, lighting or electricity.
• Passive solar systems use non-mechanical techniques of capturing, converting and distributing sunlight into usable outputs such as heating, lighting or ventilation. These techniques include selecting materials with favorable thermal properties, designing spaces that naturally circulate air and referencing the position of a building to the sun.
• Direct solar generally refers to technologies or effects that involve a single conversion of sunlight which results in a usable form of energy.
• Indirect solar generally refers to technologies or effects that involves multiple transformations of sunlight which result in a usable form of energy.

Active solar is a term which refers to the use of solar energy to actively convert the energy in sunlight into other forms. ... Solar panels are used in passive and active solar hot water systems Passive solar technologies convert sunlight into usable heat, cause air-movement for ventilation or cooling, or store heat for future use, without the assistance of other energy sources. ...

Architecture

The Zion National Park Visitor's Center incorporates several aspects of solar design.

Main article: Passive solar building design

Solar architecture uses the sun for temperature control, lighting and ventilation while minimizing negative effects such as overheating and glare. The basic elements of solar architecture are building orientation, proportion, thermal mass and window placement. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... Passive solar building design involves the modeling, selection and use of appropriate passive solar technologies to maintain the building environment at a desired temperature range (usually based around human thermal comfort) throughout the suns daily and annual cycles. ...

• The entire building can be positioned and angled to be oriented towards or away from the sun, overshadowing from other structures or natural features can be avoided or used, and the building can be set into the ground using earth sheltering techniques.
• As a rule of thumb, a solar building's axis should run lengthwise east to west and the structure should be twice as long as wide.
• Windows facing the equator should be equal to 5-7% of the building's floor space. If heating is a concern, window area facing away from the equator should be minimized.
• The thermal mass in the building should be sized to smooth out temperature swings.
• Spaces can be designed to naturally circulate air. Cooling elements such as a solar chimney can be incorporated to help with ventillation.^[17]
• Lighting quality and energy use are strongly influenced by window design. In cold climates insulated glazing with low-emissivity coatings can maximize solar gain and reduce heat losses by 30-50%. In hot climates low-emissivity coatings on the outside of window panes can be used to reduce and control solar gain.^[18]

Shadows on pavement A shadow is a region of darkness where light is blocked. ... Earth covered farm houses in Keldur, Iceland. ... World map showing the equator in red In tourist areas, the equator is often marked on the sides of roads The equator marked as it crosses Ilhéu das Rolas, in São Tomé and Príncipe. ... Thermal mass, in the most general sense, is any mass that absorbs and holds heat. ... It has been suggested that this article or section be merged with Solar Tower. ... Insulated Glazing Unit or Insulating Glass Unit (commonly referred to as IGU) is described as two or more lites of glass spaced apart and hermetically sealed to form a single glazed unit with an air space between each lite. ... Insulated Glazing Unit or Insulating Glass Unit (commonly referred to as IGU) is described as two or more lites of glass spaced apart and hermetically sealed to form a single glazed unit with an air space between each lite. ... Solar gain (also known as solar heat gain or passive solar gain) refers to the increase in temperature in a space, object or structure that results from solar radiation. ...

Lighting

Main articles: Daylighting and Light tube

The history of lighting is dominated by the use of natural light. The Romans recognized the Right to Light as early as the 6th century and English law echoed these judgements with the Prescription Act of 1832. It wasn't until the 1900s that artificial lighting took over as the main source of interior illumination. The 1973 oil and 1979 energy crises brought attention to conservation measures such as natural lighting but interest waned on both occasions with the restoration of energy supplies. Approximately 20% of the electricity used in the United States is for lighting. When daylighting techniques are appropriately applied natural light can supply interior lighting for many hours of the day.^[19] Daylighting is the practice of placing windows, or other transparent media, and reflective surfaces so that, during the day, natural light provides effective internal illumination. ... Light tubes or light pipes are used for transporting or distributing natural or artificial light. ... In English Law a right to light is a form of easement. ... Justinian I depicted on a mosaic in the church of San Vitale, Ravenna, Italy The Corpus Juris Civilis (Body of Civil Law) also known as Codex Justinianus is a fundamental work in jurisprudence, issued from 529 to 534 by order of Justinian I, Byzantine Emperor. ... Not to be confused with lightning. ... The 1973 Oil Crisis began in earnest on October 17, 1973, when the members of Organization of Arab Petroleum Exporting Countries (OAPEC, consisting of the Arab members of OPEC plus Egypt and Syria) announced, as a result of the ongoing Yom Kippur War, that they would no longer ship petroleum... Line at a gas station, June 15, 1979. ...

Daylighting is a passive solar method of using sunlight to provide illumination. Daylighting directly offsets energy use in electric lighting systems and indirectly offsets energy use through a reduction in cooling load.^[20] Although difficult to quantify, the use of natural lighting also offers physiological and psychological benefits compared to artificial lighting. Daylighting is the practice of placing windows, or other transparent media, and reflective surfaces so that, during the day, natural light provides effective internal illumination. ... Prism splitting light High Resolution Solar Spectrum Sunlight in the broad sense is the total spectrum of the electromagnetic radiation given off by the Sun. ... Not to be confused with lightning. ...

Daylighting features include building orientation, window orientation, exterior shading, sawtooth roofs, clerestory windows, light shelves, skylights and light tubes.^[21] These features may be incorporated in existing structures but are most effective when integrated in a solar design package which accounts for factors such as glare, heat gain, heat loss and time-of-use. Architectural trends increasingly recognize daylighting as a cornerstone of sustainable design. It has been suggested that window frames be merged into this article or section. ... Malmesbury Abbey, Wiltshire, England. ... The word skylight, when used alone, has several possible meanings in the English language. ... Light tubes or light pipes are used for transporting or distributing natural or artificial light. ... Passive solar building design involves the modeling, selection and use of appropriate passive solar technologies to maintain the building environment at a desired temperature range (usually based around human thermal comfort) throughout the suns daily and annual cycles. ... This time exposure photo of New York City shows sky glow, one form of light pollution. ... It has been suggested that Green design be merged into this article or section. ...

Hybrid solar lighting (HSL) is an active solar method of using sunlight to provide illumination. Hybrid solar lighting systems collect sunlight using focusing mirrors that track the sun. The collected light is transmitted via optical fibers into a building's interior to supplement conventional lighting. In single story applications, these systems are able to transmit 50% of received direct sunlight.^[22][23] Optical fibers An optical fiber (or fibre) is a glass or plastic fiber designed to guide light along its length by confining as much light as possible in a propagating form. ...

Daylight saving time (DST) utilizes solar energy by matching available sunlight to the time of the day in which it is most useful. Though DST is common in Europe and North America, most of the worlds people do not use it. ...

Water heating

Solar water heaters, on a rooftop in Jerusalem, Israel

Main articles: Solar hot water, Solar combisystem, and Solar pond

Solar hot water systems use sunlight to heat water. Commercial solar water heaters began appearing in the United States in the 1890s. These systems saw increasing use until the 1920s but were thereafter gradually replaced by relatively cheap and more reliable conventional heating fuels. The economic advantage of conventional heating fuels has varied over time resulting in periodic interest in solar hot water; however, solar hot water technologies have yet to show the sustained momentum they lost in the 1920s. That being said, the recent price spikes and erratic availability of conventional fuels is renewing interest in solar heating technologies.^[24][25] Image File history File links Size of this preview: 617 × 599 pixels Full resolution (1581 × 1536 pixel, file size: 1. ... Image File history File links Size of this preview: 617 × 599 pixels Full resolution (1581 × 1536 pixel, file size: 1. ... For other uses, see Jerusalem (disambiguation). ... Solar hot water refers to water heated by solar energy. ... A solar combisystem is a solar heating system that provides both space heating and hot water from a common array of solar thermal collectors, normally linked to an auxiliary non-solar heat source. ... A Solar pond is large-scale solar energy collector with integral heat storage for supplying thermal energy. ... Solar hot water refers to water heated by solar energy. ...

As of 2005, the total installed capacity of solar hot water systems is 88 GWth and growth is 14% per year. China is the world leader in the deployment of solar hot water systems with 80% of the market. Israel is the per capita leader in the use of solar hot water with 90% of homes using this technology.^[26][27]In the United States heating swimming pools is the most successful application of solar hot water.^[28]

Solar water heating is highly efficient (up to 86%) and is particularly appropriate for low temperature (25-65 °C) applications such as domestic hot water, heating swimming pools and space heating.

The basic components of a solar water heating systems are solar thermal collectors, a storage tank and a circulation loop.^[29] The three basic classifications of solar water heaters are:

• Batch systems which consist of a tank that is directly heated by sunlight. These are the oldest and simplest solar water heater designs, however; the exposed tank can be vulnerable to cooldown.^[30]
• Active systems which use pumps to circulate water or a heat transfer fluid.
• Passive systems which circulate water or a heat transfer fluid by natural circulation. These are also called thermosiphon systems.

Solar water heaters are also classified by the type of circulation loop used to transmit and deliver heat. These can be direct or indirect. Natural circulation refers to the ability of a fluid in a circulatory system to continue flowing without the use of pumps to drive it. ... Thermosiphon (alternatively spelled thermosyphon) refers to a method of heat exchange through a phase change heat pump that depends on gravity. ...

• Direct solar hot water systems use a single loop to heat and deliver hot water.
• Indirect solar hot water systems use a primary loop to capture heat, a heat exchanger and a secondary loop to deliver hot water.

A solar pond is a pool of salt water that collects and stores solar energy. Solar ponds were first proposed by Dr. Rudolph Bloch in 1948 after coming across reports of a lake in Hungry in which the temperature increased with depth. This effect was due to salts in the lake's waters which created a "density gradient" that prevented convection currents. A prototype was constructed in 1958 on the shores of the Dead Sea near Jerusalem. The pond consisted of layers of water that successively increased from a weak salt solution at the top to a high salt solution at the bottom. This solar pond was capable of producing temperatures of 90 °C in its bottom layer and had an estimated solar to electric efficiency of 2%. Current, representatives of this technology include a 150 KW pond in En Boqeq, Israel, and another used for industrial process heat at the University of Texas El Paso.^{[31][32] [33]} A Solar pond is large-scale solar energy collector with integral heat storage for supplying thermal energy. ... Convection is the transfer of heat by the motion of or within a fluid. ... For the sports equipment manufacturer, see Brine, Corp. ... The UTEP logo The University of Texas at El Paso, popularly known as UTEP, is a public, coeducational university, and it is a member of the University of Texas System. ...

Heating, cooling and ventilation

Main articles: Solar heating, Thermal mass, Trombe wall, and Solar chimney

• A thermal mass is a body that absorbs and holds heat. In the context of solar energy, it is a mass designed to store heat during sunny periods and release heat when sunlight levels are reduced or unavailable. A properly sized thermal mass will smooth out temperature swings and help keep rooms at a comfortable temperature throughout the day and night.

• A Trombe wall is a passive solar heating and ventilation system consisting of an air channel sandwiched between a window and a sun-facing thermal mass. During the ventilation cycle sunlight stores heat in the thermal mass and warms the air channel causing circulation through vents at the top and bottom of the wall. During the heating cycle the Trombe wall radiates stored heat.^[34]

• A transpired collector is a perforated sun-facing wall. The wall absorbs sunlight and pre-heats air as much as 22°C as it is drawn into the ventilation system. These systems are highly efficient (up to 80%) and can pay for themselves within 3-12 years in offset heating costs.^[35]

• Solar cooling can be achieved via absorption refrigeration cycles, desiccant cycles and solar mechanical processes^[36]. In 1878 Auguste Mouchout pioneered solar cooling by making ice using a solar steam engine attached to a refrigeration device.

• A solar chimney (or thermal chimney) is a passive solar ventilation system composed of a hollow thermal mass connecting the inside and outside of a building. As the chimney warms the air inside is heated causing an updraft which enhances the natural stack ventilation through a building. These systems have been in use since Roman times and are common in the Middle east.

Solar heating is a style of building construction which uses the energy of sunshine to heat a structure. ... Thermal mass, in the most general sense, is any mass that absorbs and holds heat. ... Passive solar design using an unvented trombe wall and summer shading A Trombe wall is a sun-facing wall built from material that can act as a thermal mass (such as stone, concrete, adobe or water tanks), combined with an air space, insulated glazing and vents to form a large... It has been suggested that this article or section be merged with Solar Tower. ... Thermal mass, in the most general sense, is any mass that absorbs and holds heat. ... For other uses, see Heat (disambiguation) In physics, heat, symbolized by Q, is energy transferred from one body or system to another due to a difference in temperature. ... Passive solar design using an unvented trombe wall and summer shading A Trombe wall is a sun-facing wall built from material that can act as a thermal mass (such as stone, concrete, adobe or water tanks), combined with an air space, insulated glazing and vents to form a large... In thermodynamics, a closed system, as contrasted with an isolated system, can exchange heat and work, but not matter, with its surroundings. ... Natural circulation refers to the ability of a fluid in a circulatory system to continue flowing without the use of pumps to drive it. ... The absorption refrigeration and absorption cooling attractive when there is a source of inexpensive or waste heat readily available. ... A dessicant is a hygroscopic substance that induces or sustains a state of dryness (desiccation) in its local vicinity in a moderately-well sealed container. ... Auguste Mouchout was a 19th century French inventor of the earliest solar-powered engine, converting solar energy into mechanical steam power. ... It has been suggested that this article or section be merged with Solar Tower. ... This article is about systems theory. ... An Updraft or Downdraft is refers to the vertical movement of air as a weather related phenomenom. ... Natural ventilation is the process of supplying and removing air through an indoor space by natural means. ... Ancient Rome was a civilization that grew from a small agricultural community founded on the Italian Peninsula circa the 9th century BC to a massive empire straddling the Mediterranean Sea. ... A map showing countries commonly considered to be part of the Middle East The Middle East is a region comprising the lands around the southern and eastern parts of the Mediterranean Sea, a territory that extends from the eastern Mediterranean Sea to the Persian Gulf. ...

Photovoltaics

Photovoltaic (PV) modules are composed of multiple PV cells. Two or more interconnected PV modules create an array.

Map of solar electricity potential in Europe

Main article: Photovoltaics

Solar cells, also referred to as photovoltaic cells, are devices or banks of devices that use the photovoltaic effect of semiconductors to generate electricity directly from sunlight. Until recently, their use has been limited because of high manufacturing costs. One cost effective use has been in very low-power devices such as calculators with LCDs. Another use has been in remote applications such as roadside emergency telephones, remote sensing, cathodic protection of pipe lines, and limited "off grid" home power applications. A third use has been in powering orbiting satellites and spacecraft. solar panel by BP solar at a german autobahn bridge. ... solar panel by BP solar at a german autobahn bridge. ... Image File history File links Size of this preview: 629 × 600 pixels Full resolution (800 × 763 pixel, file size: 685 KB, MIME type: image/png) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Photovoltaics ... Image File history File links Size of this preview: 629 × 600 pixels Full resolution (800 × 763 pixel, file size: 685 KB, MIME type: image/png) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Photovoltaics ... Photovoltaic tree in Styria, Austria Photovoltaics, or PV for short, is a solar power technology that uses solar cells or solar photovoltaic arrays to convert light from the sun directly into electricity. ... A solar cell, made from a monocrystalline silicon wafer A solar cell or photovoltaic cell is a device that converts light energy into electrical energy. ... A photovoltaic cell is a device that turns light into electric energy. ... A semiconductor is a solid whose electrical conductivity is in between that of a conductor and that of an insulator, and can be controlled over a wide range, either permanently or dynamically. ... For other uses, see Calculator (disambiguation). ... “LCD” redirects here. ... Aluminium anodes mounted on a steel jacket structure Cathodic protection (CP) is a technique to control the corrosion of a metal surface by making that surface the cathode of an electrochemical cell. ... For other uses, see Satellite (disambiguation). ... The Space Shuttle Discovery as seen from the International Space Station. ...

To take advantage of the incoming electromagnetic radiation from the sun, solar panels can be attached to each house or building. The panels should be mounted perpendicular to the arc of the sun to maximize usefulness. The easiest way to use this electricity is by connecting the solar panels to a grid tie inverter. However, these solar panels may also be used to charge batteries or other energy storage device. Solar panels produce more power during summer months because they receive more sunlight. A grid-tie inverter is an electrical device that allows solar power users to compliment their grid power with solar power. ... Ffestiniog pumped storage power station upper reservoir Grid energy storage lets energy producers send excess electricity over the electricity transmission grid to temporary electricity storage sites that become energy producers when electricity demand is greater. ... Prism splitting light High Resolution Solar Spectrum Sunlight in the broad sense is the total spectrum of the electromagnetic radiation given off by the Sun. ...

Total peak power of installed PV is around 6,000 MW as of the end of 2006. Installed PV is projected to increase to over 9,000 MW in 2007.^[37][38] This is only one part of solar-generated electric power. Peak power is the maximum level of work or energy output that is measured during an observation period. ...

Declining manufacturing costs (dropping at 3 to 5% a year in recent years) are expanding the range of cost-effective uses. The average lowest retail cost of a large photovoltaic array declined from $7.50 to $4 per watt between 1990 and 2005.^[39] With many jurisdictions now giving tax and rebate incentives, solar electric power can now pay for itself in five to ten years in many places. "Grid-connected" systems - those systems that use an inverter to connect to the utility grid instead of relying on batteries - now make up the largest part of the market. A photovoltaic module that is composed of individual PV cells. ... 2005 is a common year starting on Saturday of the Gregorian calendar. ... For other uses, see Inverter (logic gate) and Inverter. ... 11kV/400V-230V transformer in an older suburb of Wellington, New Zealand Electricity distribution is the penultimate stage in the delivery (before retail) of electricity to end users. ...

In 2003, worldwide production of solar cells increased by 32%.^[40] Between 2000 and 2004, the increase in worldwide solar energy capacity was an annualized 60%.^[41] 2005 was expected to see large growth again, but shortages of refined silicon have been hampering production worldwide since late 2004.^[42] Analysts have predicted similar supply problems for 2006 and 2007.^[43] General Name, Symbol, Number silicon, Si, 14 Chemical series metalloids Group, Period, Block 14, 3, p Appearance as coarse powder, dark grey with bluish tinge Standard atomic weight 28. ...

Solar power plants

Solar Two power tower surrounded by a field of heliostats.

Parabolic dishes use Stirling engines for power conversion.

Main articles: Solar thermal energy, Parabolic trough, Solar power tower, Photovoltaic power stations, Solar power plants in the Mojave Desert, and List of solar thermal power stations

Solar power plants use a variety of methods to collect sunlight and convert this energy into electricity, distill water or provide heat for industrial processes. Concentrating solar thermal power plants have traditionally been the most common type of solar power plant; however, multi-megawatt photovoltaic sites have seen recent rapid deployment. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... Image File history File links SolarStirlingEngine. ... Image File history File links SolarStirlingEngine. ... Cut away diagram of a Rhombic Drive Beta Stirling Engine Design Pink - Hot cylinder wall, Dark grey - Cold cylinder wall (with coolant inlet and outlet pipes in Yellow), Dark Green - Thermal insulation separating the two cylinder ends, Light Green - Displacer piston, Dark Blue - Power piston, Light Blue - Flywheels, Not Shown... Solar thermal energy is a technology for harnessing solar power for practical applications from solar heating to electrical power generation. ... This article does not cite any references or sources. ... The solar power tower at Solar Two in California The solar power tower (also known as Central Tower power plants or Heliostat power plants or power towers) is a type of solar furnace using a tower to receive the focused sunlight. ... Several large photovoltaic power stations have been built, mainly in Europe. ... Extent of Mojave Desert. ... This is a List of Solar thermal power stations which are operating or are under construction: Andasol 1 solar power station (Spain) Nevada Solar One (USA) PS10 solar power tower (Spain) Solar Energy Generating Systems (USA) Solar Tres Power Tower (Spain) Category: ...

Concentrating Solar Thermal (CST) systems use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam. CST technologies require direct insolation to perform properly. This requirement makes them inappropriate for significantly overcast locations.^[44] Solar thermal energy is a technology for harnessing solar power for practical applications from solar heating to electrical power generation. ... Direct insolation is the solar radiation that is transmitted directly through the atmosphere to the earths surface without interacting with atmospheric components. ...

The three basic CST technologies are the solar trough, solar power tower and parabolic dish. Each technology is capable of producing high temperatures and correspondingly high thermodynamic efficiencies but they vary in the way they track the sun and focus light. Thermodynamic efficiency (e) is defined as: where W is the absolute value of the work done in one thermodynamic cycle. ...

• Line focus/Single-axis
  • A solar trough consists of a linear parabolic reflector which concentrates light on a receiver positioned along the reflector's focal line. These systems use single-axis tracking to follow the sun. A working fluid (oil, water) flows through the receiver and is heated up to 400 °C before transferring its heat to a distillation or power generation system.^[45][46] Trough systems are the most developed CST technology. The Solar Electric Generating System (SEGS) plants in California and Plataforma Solar de Almería's SSPS-DCS plant in Spain are representatives of this technology.^[47]
• Point focus/Dual-axis
  • A power tower consists of an array of flat reflectors (heliostats) which concentrate light on a central receiver located on a tower. These systems use dual-axis tracking to follow the sun. A working fluid (air, water, molten salt) flows through the receiver where it is heated up to 1000 °C before transferring its heat to a power generation or energy storage system. Power towers are less advanced than trough systems but they offer higher efficiency and energy storage capability.^[48] The Solar Two in Daggett, California and the Planta Solar 10 (PS10) in Sanlucar la Mayor, Spain are representatives of this technology.
  • A parabolic dish or dish/engine system consists of a stand-alone parabolic reflector which concentrates light on a receiver positioned at the reflector's focal point. These systems use dual-axis tracking to follow the sun. A working fluid (hydrogen, helium, air, water) flows through the receiver where it is heated up to 1500 °C before transferring its heat to a sterling engine for power generation.^[49][48] Parabolic dish systems display the highest solar-to-electric efficiency among CST technologies and their modular nature offers scalability. The Stirling Energy Systems (SES) and Science Applications International Corporation (SAIC) dishes at UNLV and the Big Dish in Canberra, Australia are representatives of this technology.

A solar updraft tower (also known as a solar chimney or solar tower) consists of a large greenhouse which funnels into a central tower. As sunlight shines on the greenhouse the air inside is heated and expands. The expanding air flows toward the central tower where a turbine converts the air flow into electricity. A 50 kW prototype was constructed in Ciudad Real, Spain and operated for eight years before decommissioning in 1989.^[50] Sketch of a Parabolic Trough Power Plant A parabolic trough is a type of solar thermal collector. ... The solar power tower at Solar Two in California The solar power tower (also known as Central Tower power plants or Heliostat power plants or power towers) is a type of solar furnace using a tower to receive the focused sunlight. ... A Heliostat is a device that tracks the movement of the sun. ... Solar One is a pilot solar-thermal project in the Mojave Desert near Barstow, California. ... A parabolic reflector (also known as a parabolic dish or a parabolic mirror) is a reflective device formed in the shape of a paraboloid of revolution. ... The University of Nevada, Las Vegas (UNLV) is a public, coeducational university located in Las Vegas, Nevada. ... Schematic of a Solar updraft tower This article is about a type of power plant. ... The Royal Greenhouses of Laeken. ... Ciudad Real (Spanish for: Royal City) is a city in Castilla-La Mancha, Spain. ...

Cooking

Solar Cookers use sunshine as a source of heat for cooking as an alternative to fire.

Main article: Solar cooker

Solar cookers (or solar ovens) use sunlight for cooking, drying and pasteurization. Solar cookers offset fuel costs and reduce demand for local firewood. Solar cookers also improve local air quality by removing a source of smoke. The most common designs are box cookers, concentrating cookers and panel cookers. Image File history File links File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... The CooKit solar panel cooker in use in Africa A solar cooker is a way of using the suns power to cook. ... Pasteurization (or pasteurisation) is the process of heating liquids for the purpose of destroying viruses and harmful organisms such as bacteria, protozoa, molds, and yeasts. ...

• Solar box cookers consist of an insulated container with a transparent lid. Horace de Saussure developed this design in 1767 after observing: "It is a known fact, and a fact that has probably been known for a long time, that a room, a carriage, or any other place is hotter when the rays of the sun pass through glass." These cookers can be effectively used with partially overcast skies and can typically reach temperatures of 50-100°C. These are the cheapest and most widely used cooker design.^[51][52]

• Concentrating solar cookers use a parabolic reflector to concentrate light on a container positioned at the reflector's focal point. These designs cook faster and at higher temperatures (up to 315°C). As with other concentrating technologies these cookers require direct light and must be repositioned to track the sun.^[53]

• Solar Panel cookers (SPC) use flat reflectors to concentrate sunlight on a container within a transparent covering. Roger Bernard is credited with introducing panel cookers in 1994. This design uses partial concentration and will maintain effective operation with limited repositioning.

Horace-Benedict de Saussure was a French-Swiss naturalist who constructed the first known western solar oven in 1767. ...

Solar chemical

Solar chemical processes convert solar energy into chemical energy. These processes use both light (photochemical) and heat (endothermic) to drive chemical, thermochemical or thermoelectric reactions. Solar chemical reactions can be used to store solar energy or replace energy that would otherwise be required from an alternate source. Solar chemical refers to a number of possible processes that harness solar energy by absorbing sunlight in a chemical reaction in a way similar to photosynthesis in plants but without using living organisms. ... In chemistry, a chemical bond is the force which holds together atoms in molecules or crystals. ...

Electrochemical cells, commonly known as batteries, convert electrical energy into chemical energy. Solar energy can indirectly be converted into chemical energy in a system involving a photovoltaic to electrochemical cell exchange. A more direct approach involves the use of photoelectrochemical cells which use light to produce hydrogen in a process similar to the electrolysis of water. A third approach involves the use of thermoelectic devices which convert a temperature difference between dissimilar metals into an electric current between those metals. This current can be use to produce hydrogen and oxygen through the electrolysis of water. The solar pioneer Mochout envisioned using the thermoelectric effect to store solar energy for later use during darkness; however, his experiments toward this end never progressed beyond primitive devices.^[54] A demonstration electrochemical cell setup resembling the Daniell cell. ... A photoelectrochemical cell uses electromagnetic radiation including visible light to produce hydrogen, in a similar way to electrolysis of water. ... This article is about the chemical process. ... Thermogenerators are current sources which convert heat (temperature differences) directly into electrical energy. ...

Concentrating solar thermal technologies can be used to drive high temperature chemical processes.

• Ammonia can be decomposed into nitrogen and hydrogen at high temperatures (650-700°C). The stored gases can be subsequently recombined to generate heat or electricity via a fuel cell. A prototype system was constructed at the Australian National University.^[55][56]

• Zinc Oxide (ZnO) can be decomposed at high temperatures (1200-1750°C). The resulting pure zinc can be marketed directly. Alternatively, the zinc can be reacted with water at (350°C) to produce ZnO and hydrogen.^[57][58]

• Water can be directly dissociated at high temperatures (2300-2600°C). These process have so far been limited due to their high level of complexity and low solar to hydrogen efficiency (1-2%).^[59] An alternate path of research is investigating solar thermochemical cycles that can be used to dissociate water at lower temperatures. Thermochemical cycles are currently at the prototype stage.^[60][61]

• Concentrating solar thermal has also been investigated as a direct thermal method of producing aluminum.^[62]

While not a technology, photosynthesis is arguably the most important photochemical interaction. A diverse biology has developed capable of photosynthesizing light in the visible, ultraviolet, near infrared and far infrared regions of the electromagnetic spectrum. For other uses, see Ammonia (disambiguation). ... The leaf is the primary site of photosynthesis in plants. ... Photochemistry is the study of the interaction of light and chemicals. ...

Salt evaporation ponds are shallow man-made ponds designed to extractsalt from sea water. The seawater is fed into large ponds and water is drawn out through natural evaporation speeded by heating from the rays of the sun, which allows the remaining salt to be subsequently harvested. San Francisco Bay salt ponds Salt evaporation pond in Ile de Ré, France. ... Two people reflected in a fish pond A pond is typically a man made body of water smaller than a lake. ... For other uses, see Salt (disambiguation). ... Sea water is water from a sea or ocean. ... This article or section is in need of attention from an expert on the subject. ...

Solar phase change material energy storage

Solar energy can be stored thermochemically with phase change materials (PCM). Devices of this type which store latent heat can be thought of as heat batteries. Phase change materials are classified as organic (paraffins, fatty acids) and inorganic (salts, metals,alloys).^[63]

• A Paraffin wax thermal storage system consists of a solar hot water loop connected to a paraffin wax tank. During the storage cycle, hot water flows through the storage tank melting the paraffin wax. The enthalpy of fusion for paraffin wax is 210-230 kJ/kg. During the heating cycle, stored heat is extracted from the tank as the wax resolidifies. These systems heat air and water up to 64°C and can reduce conventional energy use by 50%-70%. ^[64][65]

• Eutectic salts such as Glauber's salt can also be employed in thermal storage systems. Glauber's salt are relatively inexpensive and readily available and can store 347 kJ/kg and deliver heat at 64°C. The Dover house in Dover, Massachusetts was the first to use a Glauber's salt heating system in 1948. ^[66][67]

Paraffin is a common name for a group of high molecular weight alkane hydrocarbons with the general formula CnH2n+2, where n is greater than about 20. ... Standard enthalpy change of fusion of period three. ... Sodium sulfate is an important compound of sodium. ...

Solar vehicles

The solar powered car The Nuna 3 built by the Dutch Nuna team

Helios UAV in flight

Main articles: Helios Prototype, Electric boat, and Solar balloon

Development of a practical solar powered car has been an engineering goal for 20 years. The center of this development is the World Solar Challenge, a biannual solar powered car race over 3021 km (1877mi) through central Australia from Darwin to Adelaide. The race's stated objective is to promote research into solar-powered cars. Teams from universities and enterprises participate. In 1987 when it was founded, the winner's average speed was 67 km/h (42 mph).^[68] By the 2005 race this had increased to an average speed of greater than 100 km/h (62 mph), even though the cars were faced with the 110 km/h (68 mph) South Australia speed limit.^[69] ImageMetadata File history File links Download high resolution version (2048x1368, 426 KB) File links The following pages link to this file: Nuna ... ImageMetadata File history File links Download high resolution version (2048x1368, 426 KB) File links The following pages link to this file: Nuna ... For the popping bean, see common bean. ... Image File history File links Helios_in_flight. ... Image File history File links Helios_in_flight. ... Helios Prototype UAV in flight Helios Prototype is the name of a solar- and fuel cell system-powered unmanned aerial vehicle that NASA tested. ... While most boats on the water today are powered by diesel engines, and sail power and gasoline engines are also popular, it is perfectly feasible to power boats by electricity too. ... A solar balloon is a black balloon that is filled with air. ... The winners of the 2003 American Solar Challenge A solar car is an electric vehicle powered by solar energy obtained from solar panels on the surface of the car. ... The Nuna 3 of the hattrick winning Dutch Nuna team The World Solar Challenge is a solar powered-car race over 3021 km through central Australia from Darwin to Adelaide. ... “Port Darwin” redirects here. ... For other uses, see Adelaide (disambiguation). ... Kilometres per hour (American spelling: kilometers per hour) is a unit of both speed (scalar) and velocity (vector). ... Capital Adelaide Government Constitutional monarchy Governor Marjorie Jackson-Nelson Premier Mike Rann (ALP) Federal representation  - House seats 11  - Senate seats 12 Gross State Product (2004-05)  - Product ($m)  $59,819 (5th)  - Product per capita  $38,838/person (7th) Population (End of September 2006)  - Population  1,558,200 (5th)  - Density  1. ...

Helios, named after the Greek sun god of the same name, was a prototype solar powered unmanned aircraft. AeroVironment, Inc. developed the vehicle under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. The £124 million Taranis UAV built by BAE Systems An unmanned aerial vehicle (UAV) is an aircraft with no onboard pilot. ... AeroVironment is a California technology company that is primarily involved in energy systems, electric vehicle systems, and unmanned aerial vehicles. ... The Environmental Research Aircraft and Sensor Technology, or ERAST project is a NASA initiative to develop new technologies for civil use of remotely operated unmanned aerial vehicles (UAVs). ...

On 13 August, 2001, it set an unofficial world record for sustained altitude by a winged aircraft. It sustained flight at above 96,000 feet (29,250 m) for forty minutes, and at one time it flew as high as 96,863 feet (29,524 m). Later, in June 2003, the prototype broke up and fell into the Pacific Ocean about ten miles (16 km) west of the Hawaiian Island Kauai. This is a list of aviation-related events from 2001: Events April: The unmanned aircraft Global Hawk flies automatically from Edwards AFB in the US to Australia non-stop and unrefuelled. ... A world record is the best performance in a certain discipline, usually a sports event. ... Altitude is the elevation of an object from a known level or datum. ... For other uses, see Wing (disambiguation). ... “Flying Machine” redirects here. ... This is a list of aviation-related events from 2003: Events February 1The Space Shuttle Columbia disintegrates, killing all seven occupants. ... “Miles” redirects here. ... A compass rose with west highlighted This article refers to the cardinal direction; for other uses see West (disambiguation). ... Kauai (Hawaiian IPA pron. ...

The first practical solar boat was probably constructed in 1975 in England (see Electrical Review Vol 201 No 7 12 August 1977). By 1995 passenger boats began appearing and are now used extensively.[14] Solar powered boats have advanced sufficiently to cross the Atlantic. The first crossing of the Atlantic Ocean was achieved in the winter of 2006/2007 by the solar catamaran sun21.[15]

A solar balloon is a black balloon that is filled with air. As sunlight shines on the balloon the air inside is heated and expands. This causes an upward buoyancy force. As such, the balloon functions like a hot air balloon. Some solar balloons are large enough for human flight but usage at the moment is restricted to the toy market. A solar balloon is a black balloon that is filled with air. ... In physics, buoyancy is the upward force on an object produced by the surrounding fluid (i. ...

Desalination and disinfection

Main articles: desalination, Solar still, and Solar water disinfection

A solar still uses solar energy to distill water. A few basic types of solar stills are cone shaped, boxlike, and pit. For cone solar stills, impure water is inserted into the container, where it is evaporated by the sun through clear plastic. The pure water vapor condenses on top and drips down to the side, where it is collected and removed. The most sophisticated of these are the box shaped types. The least sophisticated are the pit types. Shevchenko BN350 desalination unit situated on the shore of the Caspian Sea. ... Solar still built into a pit in the ground A solar still is a very simple device for distilling water, powered by the heat of the sun. ... This article or section is in need of attention from an expert on the subject. ... Image File history File links This is a diagram of an evaporation still in cross-section that I made for How to obtain water in the wilderness using Micrografx Designer software. ... יחכיטכיגיגיוגקאטגקעיגקDistillation is a method of separating chemical substances based on differences in their volatilities in a boiling liquid mixture. ... It has been suggested that multiple sections of steam be merged into this article or section. ...

Solar water disinfection (SODIS) is a method of disinfecting water using sunlight. The basic process involves filling a clear container 3/4 with water, shaking the container vigorously for 20 seconds, topping off the container and placing it in the sun. Shaking the container allows for the water to become aerated which amplifies the disinfecting effect of the sunlight. SODIS methods treat water through three synergistic radiation mechanisms.^[70][71]

• UV-A (wavelength 320-400nm) which react with oxygen dissolved in the water produces highly reactive forms of oxygen (oxygen free radicals and hydrogen peroxides) in the water. These reactive forms of oxygen kill the microorganisms.
• UV-A also interferes with the reproduction cycle of bacteria by damaging their DNA
• Infrared heating the water. If the water temperatures raises above 50°C, the disinfection process is three times faster.

For other uses, see Ultraviolet (disambiguation). ...

Energy storage

Main article: Grid energy storage

A Solar powered garden lamp

Solar energy is primarily stored in the form of heat in hot water and thermal masses or chemical energy in batteries. The storage of excess solar energy allows for the availability of this energy during hours of darkness or cloud cover. Ffestiniog pumped storage power station upper reservoir Grid energy storage lets energy producers send excess electricity over the electricity transmission grid to temporary electricity storage sites that become energy producers when electricity demand is greater. ... Image File history File links Size of this preview: 450 × 600 pixelsFull resolution (1536 × 2048 pixel, file size: 1. ... Image File history File links Size of this preview: 450 × 600 pixelsFull resolution (1536 × 2048 pixel, file size: 1. ...

• Using traditional batteries
• Thermal mass
• Thermochemical storage (heat batteries)
• Molten salt^[72]

Storage always has an extra stage of energy conversion, with consequent energy losses, increasing the total capital costs. One way around this is to export excess power to the power grid, drawing it back when needed. This appears to use the power grid as a battery but in fact is relying on conventional energy production through the grid during the night. However, since the grid always has a positive outflow, the result is exactly the same. Symbols representing a single Cell (top) and Battery (bottom), used in circuit diagrams. ... Thermal mass, in the most general sense, is any mass that absorbs and holds heat. ...

Electric power costs are highly dependent on the consumption per time of day, since plants must be built for peak power (not average power). Expensive gas-fired "peaking generators" must be used when base capacity is insufficient. Fortunately for solar, solar capacity parallels energy demand; since much of the electricity is for removing heat produced by too much solar energy (using conditioners). This is less true in the winter when the peak energy use is in the early evening when food is being prepared and lighting, heating, and entertainment equipment loads are higher. Winter heating loads can be time shifted by storing thermal energy in bulk materials such as rock, water, or thermal phase transition materials such as glauber's salt or wax, provided solar illumination is sufficient. Wind power complements solar power since it can produce energy when there is no sunlight but this advantage is highly dependant upon local and seasonal wind availability. Sodium sulfate is an important compound of sodium. ... candle wax This page is about the substance. ... An example of a wind turbine. ...

Solar power by country

See the articles for individual countries listed at Category:Solar power by country

Development, deployment and economics

Main article: Deployment of solar power to energy grids

Solar energy is in general not economically competitive compared to fossil fuels. Other than market forces, solar industry needs government sponsorship to help generate enough momentum in the solar market. The following trends are a few examples by which the solar market is being helped to attain critical mass so that it becomes competitively sustainable : Deployment of solar power depends largely upon local conditions and requirements. ...

• Government grants for research in solar technology to make the production cheaper and generation more efficient. ^[73]

• Many countries and states have implemented incentives to encourage consumers to consider solar power. Examples include government tax subsidies, partial copayment schemes and various rebates over purchase costs of solar devices. These are meant to relieve some pressure off the consumer and entice them not to fear the high initial deployment investments. ^[74]

• Adoption of an energy policy where the consumer can connect their local solar power generators to the local grid, and reverse feed the grid with the unconsumed extra power. The state power authority guarantees an attractive purchase price for the power that is reverse metered. This has been especially popular in Germany and Japan. ^[75]

• Development of solar loan programs, with attractive return rates, to buffer the initial deployment costs and entice consumers to consider and purchase solar PV systems. The most famous example is the solar loan program sponsored by UNEP helping 100000 people finance solar power systems in India. ^[76] Success in India's solar program has led to similar projects in other parts of developing world like Tunisia, Morocco, Indonesia and Mexico.

Photovoltaics is gaining credence among private investors as having the potential to grow into the next big industry. Many companies and venture capitalists are investing in photovoltaic development and manufacturing. This trend is particularly visible in Silicon valley, California. ^{[77] [78] [79]} Nanotechnology manufacturing using CIGS solar cells promises to produce electricity at a cost of around 5¢/kwh and sell for $ 0.36 per peak watt,^[80] approximately 10 times less than average 2007 prices for solar panels.^[81] The Indian Solar Loan Programme, supported by the United Nations Environment Programme has won the prestigious Energy Globe World award for Sustainability for helping to establish a consumer financing program for solar home power systems. ... For the Nintendo 64 game, see Space Station Silicon Valley. ... Official language(s) English Capital Sacramento Largest city Los Angeles Largest metro area Greater Los Angeles Area  Ranked 3rd  - Total 158,302 sq mi (410,000 km²)  - Width 250 miles (400 km)  - Length 770 miles (1,240 km)  - % water 4. ... Buckminsterfullerene C60, also known as the buckyball, is the simplest of the carbon structures known as fullerenes. ... Copper indium gallium selenide (CIGS) is a new semiconductor material comprising copper, indium, gallium, and selenium, CuInGaSe2. ...

Deployment of solar power depends largely upon local conditions and requirements. All industrialised nations share a need for electricity and it is believed that solar power will increasingly be used as an option for electricity supply. The Very Large Scale Photovoltaic Power Generation (VLS-PV) proposal argues that "PV systems could generate many times the current primary global energy supply".^[82] To compensate for night time energy demands they would need to be complemented with pumped storage. Diagram of the TVA pumped storage facility at Racoon Mountain Pumped storage hydroelectricity is a method of storing and producing electricity to supply high peak demands by moving water between reservoirs at different elevations. ...

Solar energy associations

• ISES: International Solar Energy Society International NGO supporting renewable and sustainable technologies.
• ASES: American Solar Energy Association US organization supporting solar energy, efficiency and sustainable technologies.
• SEIA: Solar Energy Industries Association US trade association of solar energy manufacturers, dealers, distributors, contractors
• Canadian Solar industry Association
• See also: Photovoltiac Industry Associations

NGO is an abbreviation or code for: Non-governmental organization Nagoya Airport (IATA code) This is a disambiguation page &#8212; a navigational aid which lists other pages that might otherwise share the same title. ... Photovoltaic tree in Styria, Austria Photovoltaics, or PV for short, is a solar power technology that uses solar cells or solar photovoltaic arrays to convert light from the sun directly into electricity. ...

Solar energy research institutes

There are many research institutions and departments at universities around the world who are active in solar energy research. Countries which are particularly active include Germany, Spain, Japan, Israel, Australia, China, and the USA.

• National Renewable Energy Laboratory NREL
• Centre for Renewable Energy Systems Technology, at Loughborough University
• Centre for Sustainable Energy Systems at the Australian National University
• Florida Solar Energy Center
• Solar Energy Laboratory at UW Madison
• See also: Photovoltaics research institutes

The Australian National University, or ANU, is a public university located in Canberra, Australia. ... The University of Wisconsin–Madison is a public university located in Madison,Wisconsin. ... Photovoltaic tree in Styria, Austria Photovoltaics, or PV for short, is a solar power technology that uses solar cells or solar photovoltaic arrays to convert light from the sun directly into electricity. ...

See also

Energy Portal

Image File history File links Crystal_128_energy. ... (Redirected from 1973 energy crisis) United States, drivers of vehicles with odd numbered license plates were allowed to purchase gasoline only on odd-numbered days of the month, while drivers with even-numbers were limited to even-numbered days. ... In physics, absorption is the process by which the energy of a photon is taken up by another entity, for example, by an atom whose valence electrons make a transition between two electronic energy levels. ... Comes (genitive: comitis) is the Latin word for companion, either individually or as a member of a collective known as comitatus (compare comitatenses), especially the suite of a magnate, in some cases large and/or formal enough to have a specific name, such as a cohors amicorum. ... Deployment of solar power depends largely upon local conditions and requirements. ... This article is about energy crises in general. ... Energy development is the ongoing effort to provide sustainable energy resources through knowledge, skills, and constructions. ... Energy storage is the storing of some form of energy that can be drawn upon at a later time to perform some useful operation. ... The United Kingdoms Climate Change Programme was launched by the British government in response to its commitment to the Kyoto Protocol on global warming. ... It has been suggested that this article or section be merged into energy development. ... Green energy is a term used by some environmentalists to describe what they deem to be environmentally friendly sources of power. ... Global dimming is the gradual reduction in the amount of global direct irradiance at the Earths surface that was observed for several decades after the start of systematic measurements in 1950s. ... The list of conservation topics is a link page for the conservation of both the natural environment and the built environment. ... It has been suggested that Wind turbines (UK domestic) be merged into this article or section. ... A diagram illustrating the emission of electrons from a metal plate, requiring energy gained from an incoming photon to be more than the work function of the material. ... Photovoltaic tree in Styria, Austria Photovoltaics, or PV for short, is a solar power technology that uses solar cells or solar photovoltaic arrays to convert light from the sun directly into electricity. ... Renewable energy utilizes natural resources such as sunlight, wind, tides and geothermal heat, which are naturally replenished. ... It has been suggested that Portable air conditioner be merged into this article or section. ... A solar balloon is a black balloon that is filled with air. ... The winners of the 2003 American Solar Challenge A solar car is an electric vehicle powered by solar energy obtained from solar panels on the surface of the car. ... A solar cell, made from a monocrystalline silicon wafer A solar cell or photovoltaic cell is a device that converts light energy into electrical energy. ... Solar heating is a style of building construction which uses the energy of sunshine to heat a structure. ... Solar gain (also known as solar heat gain or passive solar gain) refers to the increase in temperature in a space, object or structure that results from solar radiation. ... This article is in need of attention. ... Extent of Mojave Desert. ... An artists depiction of a solar satellite, which could send energy wirelessly to a space vessel or planetary surface. ... The solar power tower at Solar Two in California The solar power tower (also known as Central Tower power plants or Heliostat power plants or power towers) is a type of solar furnace using a tower to receive the focused sunlight. ... Solar irradiance spectrum at top of atmosphere. ... Solar thermal energy is a technology for harnessing solar power for practical applications from solar heating to electrical power generation. ... A backyard installation of passive single–axis trackers, DC rated at 2340 watts. ... Schematic of a Solar updraft tower This article is about a type of power plant. ... It has been suggested that Green design be merged into this article or section. ... Timeline of solar energy // Timeline 1900 1901 - Nikola Tesla receives the patent US685957, Apparatus for the Utilization of Radiant Energy, and US685958, Method of Utilizing of Radiant Energy. 1902 - Philipp von Lenard observes the variation in electron energy with light frequency. ... Logo of TREC The Trans-Mediterranean Renewable Energy Cooperation (TREC)[1] is an initiative of the Club of Rome, the Hamburg Climate Protection Foundation and the National Energy Research Center of Jordan (NERC). ...

References

Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 290th day of the year (291st in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 290th day of the year (291st in leap years) in the Gregorian calendar. ... Robert Whittaker (1920-1980) was an American vegetation ecologist, active in the 1950s through the 1970s. ... Gene Likens is an American ecologist and a leading pioneer in the study of acid rain. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 247th day of the year (248th in leap years) in the Gregorian calendar. ... is the 332nd day of the year (333rd in leap years) in the Gregorian calendar. ... is the 247th day of the year (248th in leap years) in the Gregorian calendar. ... is the 86th day of the year (87th in leap years) in the Gregorian calendar. ... is the 247th day of the year (248th in leap years) in the Gregorian calendar. ... is the 87th day of the year (88th in leap years) in the Gregorian calendar. ... is the 247th day of the year (248th in leap years) in the Gregorian calendar. ... is the 11th day of the year in the Gregorian calendar. ... is the 247th day of the year (248th in leap years) in the Gregorian calendar. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 247th day of the year (248th in leap years) in the Gregorian calendar. ... is the 247th day of the year (248th in leap years) in the Gregorian calendar. ... is the 247th day of the year (248th in leap years) in the Gregorian calendar. ...

External links

• White Paper Discussing the use of Carbon Finance to Develop Solar Power.
• Florida Solar Innovators.
• Scientific calculation of sun exposure. (in French)
• Solar Power-Renewable energy resource.

Wikimedia Commons has media related to:

Solar energy

• Find solar/calculator (US DOE/ASES/SEPA)
• American Solar Energy Society
• Solar energy on Hydrogenews
• Solar energy ROI calculator for Spain. (in spanish)