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"Ever since ancient Romans installed glass and mica around their southern-facing door entrances, people have been finding ways to harness the power of the sun. From those origins, solar energy has slowly progressed into a viable source for powering your home. Other People Are Reading"

"eothermal energy in the United States continues to be an area of considerable activity. In 2012, the United States led the world in geothermal electricity production with 3,386 megawatts (MW) of installed capacity;[1][2] the largest group of geothermal power plants in the world is located at The Geysers, a geothermal field in California.[3] The United States generates an average of 15 billion kilowatt hours of geothermal power per year, comparable to burning some 25 million barrels (4,000,000 m3) of oil or 6 million short tons of coal per year.[4] Geothermal power plants are largely concentrated in the western states. They are the fourth largest source of renewable electricity, after hydroelectricity, biomass, and wind power. A geothermal resource assessment shows that nine western states together have the potential to provide over 20 percent of national electricity needs.[4][5]"

wind turbine impacts 

"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

"Wave power does not cause any greenhouse gases and is a form of renewable energy as we will simply never run out of waves. Even though equipment represents a considerable financial commitment, the fuel is free of charge and never limited by geopolitical borders. Finally, the damage to the natural environment is considered to be minimal and thus it will help stop climate change."

"Although fuel cells are more expensive than fossil fuels, it is predicted that in the near future, fuel cell power will be less expensive and more efficient. The cost is an enticing advantage for the future."

"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."

"Tidal Turbines Tidal turbines look like wind turbines. They are arrayed underwater in rows, as in some wind farms. The turbines function best where coastal currents run between 3.6 and 4.9 knots (4 and 5.5 mph). In currents of that speed, a 49.2-foot (15-meter) diameter tidal turbine can generate as much energy as a 197-foot (60-meter) diameter wind turbine. Ideal locations for tidal turbine farms are close to shore in water 65.5-98.5 feet (20-30 meters) deep."

where its used

"Some of the oldest ocean energy technologies use tidal power. All coastal areas experience two high tides and two low tides over a period of slightly more than 24 hours. For those tidal differences to be harnessed into electricity, the difference between high and low tides must be more than 16 feet (or at least 5 meters). However, there are only about 40 sites on Earth with tidal ranges of this magnitude."

How it works

oceanic tides 

The second type is based on utilizing the fast-flowing marine currents caused by tidal action....it is a truly sustainable energy source which is also very predictable. It is not subject to the vagaries of weather or climate change, and while the energy varies, it follows a predictable pattern that is known many years in advance.

" costs are expected to fall to between 5 and 7 cents/kWhr."

"no it doesn't if it does what does power windmills,wind,where do that come from huh? so that's wrong, it comes from the sun"

ware tide energy comes from     

"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."