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" Solar cells are made of the same kinds of semiconductor materials, such as silicon, used in the microelectronics industry. For solar cells, a thin semiconductor wafer is specially treated to form an electric field, positive on one side and negative on the other. When light energy strikes the solar cell, electrons are knocked loose from the atoms in the semiconductor material. If electrical conductors are attached to the positive and negative sides, forming an electrical circuit, the electrons can be captured in the form of an electric current -- that is, electricity. This electricity can then be used to power a load, such as a light or a too"

"The photoelectric effect was first noted by a French physicist, Edmund Bequerel, in 1839, who found that certain materials would produce small amounts of electric current when exposed to light. In 1905, Albert Einstein described the nature of light and the photoelectric effect on which photovoltaic technology is based, for which he later won a Nobel prize in physics. The first photovoltaic module was built by Bell Laboratories in 1954. It was billed as a solar battery and was mostly just a curiosity as it was too expensive to gain widespread use. In the 1960s, the space industry began to make the first serious use of the technology to provide power aboard spacecraft. Through the space programs, the technology advanced, its reliability was established, and the cost began to decline. During the energy crisis in the 1970s, photovoltaic technology gained recognition as a source of power for non-space applications."

"China has also laid claims to having invented windmills around 2,000 years ago, but the first documented claims appear in the 1200's. Around 250 A.D. the Romans introduced windmills into their culture and in the 700's so did Afghanistan. The Afghanistan windmills were also of the vertical axis style and cloth sails or reed matting was developed to catch the air. These windmills were used to grind corn and sugarcane plus draw water. In the 13th century Holland started developing large horizontal axis windmills. These four-blade windmills were larger, carried more torque and wind speed and could do more work than other windmills previously designed. The Holland windmills were also being used to grind grains and to drain part of the Rhine River. In the 19th century Denmark had an estimated 2,500 windmills and in the U. S. windmills were starting to be used to pump water. The Halladay windmill of 1854 is one such example of this. The first windmill in the world built for electrical production was in 1887 in Scotland built by Professor James Blyth. A year later in 1888 in the U. S. Charles Brush of Cleveland, Ohio built a large wind turbine used to generate electricity."

" In 2005, EPRI was first to study representative sites (Knik Arm, AK; Tacoma Narrows, WA; Golden Gate, CA; Muskeget Channel, MA; Western Passage, ME) without mapping the resources [1]. "

"The initial use of wind power was by Egyptians in 3000 B.C. to move their sailboats. Windmills were first used to grind grain anywhere from 2000 to 4000 years ago in ancient Persia or Babylon; crusaders brought the windmill idea back to Europe with them in the 11th century A.D. In the 1930s, windmills in rural areas of the U.S. pumped water and generated electricity."

In the 1930s, windmills in rural areas of the U.S. pumped water and generated electricity.

The initial use of wind power was by Egyptians in 3000 B.C. to move their sailboats. Windmills were first used to grind grain anywhere from 2000 to 4000 years ago in ancient Persia or Babylon; crusaders brought the windmill idea back to Europe with them in the 11th century A.D.

"First, let's clarify where waves come from: sun makes wind and wind makes waves."

when it was first made 

Lignocellulosic biofuels are predicted by oil industry body CONCAWE [1] to reduce greenhouse gas emissions by around 90% when compared with fossil petroleum, in contrast first generation biofuels were found to offer savings of 20-70%

"The first fuel cell was built in 1839 by Sir William Grove, a Welsh judge and gentleman scientist, who conducted dozens of experiments using his "gas battery."  More than a century later, equipment manufacturer Allis Chalmers plowed a Wisconsin alfalfa field using fuel cell-powered tractor (1959).  Serious interest in the fuel cell as a practical energy generator did not begin until the 1960′s, when the U.S. space program chose fuel cells over riskier nuclear power and more expensive solar energy, using fuel cells to furnish power for the Gemini and Apollo spacecraft and electricity and water for the space shuttle.  Also in the 1960s, the first passenger vehicle, a prototype van, was built by GM (1966); major auto manufacturers began more concerted fuel cell development efforts in the 1990s."

"Archaeological evidence shows that the first human use of geothermal resources in North America occurred more than 10,000 years ago with the settlement of Paleo-Indians at hot springs. The springs served as a source of warmth and cleansing, their minerals as a source of healing. While people still soak in shallow pools heated by the earth, engineers are developing technologies that will allow us to probe more than 10 miles below the earth's surface in search of geothermal energy. We invite you to study the timeline of the recent history of geothermal energy in the United States."

"Today's photovoltaic systems are used to generate electricity to pump water, light up the night, activate switches, charge batteries, supply power to the utility grid, and much more. 1839: Nineteen-year-old Edmund Becquerel, a French experimental physicist, discovered the photovoltaic effect while experimenting with an electrolytic cell made up of two metal electrodes. 1873: Willoughby Smith discovered the photoconductivity of selenium. 1876: Adams and Day observed the photovoltaic effect in solid selenium. 1883: Charles Fritts, an American inventor, described the first solar cells made from selenium wafers. 1887: Heinrich Hertz discovered that ultraviolet light altered the lowest voltage capable of causing a spark to jump between two metal electrodes. 1904: Hallwachs discovered that a combination of copper and cuprous oxide was photosensitive. Einstein published his paper on the photoelectric effect. 1914: The existence of a barrier layer in PV devices was reported. 1916: Millikan provided experimental proof of the photoelectric effect. 1918: Polish scientist Czochralski developed a way to grow single-crystal silicon. 1923: Albert Einstein received the Nobel Prize for his theories explaining the photoelectric effect. 1951: A grown p-n junction enabled the production of a single-crystal cell of germanium. 1954: The PV effect in Cd was reported; primary work was performed by Rappaport, Loferski and Jenny at RCA. Bell Labs researchers Pearson, Chapin, and Fuller reported their discovery of 4.5% efficient silicon solar cells; this was raised to 6% only a few months later (by a work team including Mort Prince). Chapin, Fuller, Pearson (AT&T) submitted their results to the Journal of Applied Physics. AT&T demonstrated solar cells in Murray Hill, New Jersey, then at the National Academy of Science Meeting in Washington, DC. 1955: Western Electric began to sell commercial licenses for silicon PV technologies; early successful products included PV-powered dolla

how long has wind industry existed in the united states

Tidal hydropower energy has various advantages. The first of these is reliability and consistency. Other alternative energy sources like wind and solar can have varying amounts of energy generated depending on the weather conditions. Tidal power energy can generate electricity by the clock and indefinitely. This means that shortages can be easily avoided. In addition, tidal turbines are efficient when it comes to generating energy. They can convert about 80 percent of the energy into electricity. Wind and solar energy generators convert much less. Of course, another great benefit of tidal power renewable energy is that it is environmentally friendly. There are no CO2 emissions that are damaging to the atmosphere or Sulfur Dioxide emissions responsible for acid rain.

"First used in about 1890, "photovoltaic" has two parts: photo, derived from the Greek word for light, and volt, relating to electricity pioneer Alessandro Volta. And this is what photovoltaic materials and devices do-they convert light energy into electrical energy, as French physicist Edmond Becquerel discovered as early as 1839. Becquerel discovered the process of using sunlight to produce an electric current in a solid material. But it took more than another century to truly understand this process. Scientists eventually learned that the photoelectric or photovoltaic effect caused certain materials to convert light energy into electrical energy at the atomic level. PV systems are already an important part of our daily lives. Simple PV systems provide power for small consumer items such as calculators and wristwatches. More complicated systems provide power for communications satellites, water pumps, and the lights, appliances, and machines in some homes and workplaces. Many road and traffic signs also are now powered by PV. In many cases, PV power is the least expensive form of electricity for these tasks."

"The first hard core environmentalist I ever encountered in life taught my 8th grade energy class at Estacada Junior High, a course that President Carter's brand new Department of Education had mandated upon us a decade before as a symbolic gesture to show he cared about America's energy future. Despite an overall policy of separating church and state, in this class it was the gospel that we would deplete all fossil fuels by the year 2000. Back when "2000" was preceded by "THE YEAR" it seemed so far away didn't it? The only lasting lesson this course taught me was a healthy skepticism of government mandated indoctrination."

"Hot springs have been used for bathing at least since paleolithic times[9] The oldest known spa is a stone pool on China's Lisan mountain built in the Qin dynasty in the 3rd century BC, at the same site where the Huaqing Chi palace was later built. In the first century AD, Romans conquered Aquae Sulis, now Bath, Somerset, England, and used the hot springs there to feed public baths and underfloor heating. The admission fees for these baths probably represent the first commercial use of geothermal power. The world's oldest geothermal district heating system in Chaudes-Aigues, France, has been operating since the 14th century.[10] The earliest industrial exploitation began in 1827 with the use of geyser steam to extract boric acid from volcanic mud in Larderello, Italy."

how long has solar energy been around?