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"The PV effect was discovered in 1954, when scientists at Bell Telephone discovered that silicon (an element found in sand) created an electric charge when exposed to sunlight. Soon solar cells were being used to power space satellites and smaller items like calculators and watches. Today, thousands of people power their homes and businesses with individual solar PV systems. Utility companies are also using PV technology for large power stations. "

"Advantages: Solar power gives you a return on your investment, while paying your utility for electricity gives you 0% return. Solar energy is renewable unlike the conventional resources (coal, oil) which will inevitably run out. Non-polluting, no carbon dioxide like fossil fuels Free except for capital expenses. Longevity - solar panels can last over twenty years Low maintenance - solar panels require very little upkeep Independence - an off-grid system allows you to break free from the electrical grid Environmentally friendly because the conversion of energy doesn't produce any carbon dioxide. It comes from the sun, which, unless you are in The South or North pole, comes out almost everyday Solar power is better for the environment, compared to burning fossil fuels and other electrical power. sun is renewable You get clean energy without harming the environment [in term of carbon emissions] , in certain countries, excessive power generated can be sold back to local electricity provider reduces pollution helps create jobs - shores up economy - to build -> you hire - innovate-maintain - basically economic activities reduced dependence on fossil fuels Once installed, the power is free It is environmentally friendly and no pollution is associated with solar power You can sell your excess power back to the power companies It can be installed anywhere You can use batteries to store power for use at night Energy from the sun is renewable, that is, it keeps on coming It is free It does no damage to the earth or its atmosphere It produces no carbon dioxide It doesn't have to be dug up from the ground like coal, oil, natural gas, or uranium It doesn't have to be cut down, like wood from forests. It produces clean, green power in the form of electricity and can be used to power just about everything we need. There is more solar energy landing on the earth every day than it would take to supply the world for a year. Solar energy can heat swimming pools, power calcul

how long has solar energy been around?

"Scientists track changes to the planet's temperature in many ways. Land-based weather stations and ocean buoys in every corner of the world monitor temperatures constantly."

A fuel cell produces electricity directly from the reaction of hydrogen and oxygen. The only byproduct is water. A fuel-cell vehicle utilizes the electricity produced by the fuel cell to power motors at the vehicle's wheels. Fuel-cell vehicles are similar to battery-electric vehicles in that they are powered by electricity, but they do not have to be recharged like battery vehicles.

On Earth, hydrogen is found in combination with other elements such as carbon (hydrocarbons), oxygen (water) and nitrogen (ammonia). Although hydrogen may sometimes be used as a fuel, it is most often used as an energy carrier, such as electricity, and not an energy source. To make hydrogen a usable, stand-alone fuel, it must be separated from these other elements by chemical, thermal or electrochemical processes.

The article we read in class. Use the summary we wrote or refer to this.

"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."

"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

"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."

Controlling factor of electric power.

"The U.S. Department of Energy found that heat pumps can save a typical home hundreds of dollars in energy costs each year, with the system typically paying for itself in 8 to 12 years. Tax credits and other incentives can reduce the payback period to 5 years or less.10                                                  "

"Heat from the earth can be used as an energy source in many ways, from large and complex power stations to small and relatively simple pumping systems. This heat energy, known as geothermal energy, can be found almost anywhere-as far away as remote deep wells in Indonesia and as close as the dirt in our backyards. FROM OUR BLOG The Latest on Renewable Energy from Our Experts and Analysts Will Clean Energy Research and Development Be Sequestered? Laura Wisland PTC Extension Already Making a Big Difference for Wind Steve Clemmer The Local Energy Movement: Coming to a Town Near You Laura Wisland Subscribe to the Energy blog feed Many regions of the world are already tapping geothermal energy as an affordable and sustainable solution to reducing dependence on fossil fuels, and the global warming and public health risks that result from their use. For example, more than 8,900 megawatts (MW) of large, utility-scale geothermal capacity in 24 countries now produce enough electricity to meet the annual needs of nearly 12 million typical U.S. households (GEA 2008a). Geothermal plants produce 25 percent or more of electricity in the Philippines, Iceland, and El Salvador."

"The growth in wind power capacity has shown no signs of slowing, even in these tough economic times. For two years running there has been more new wind power capacity installed than any other power generating technology in Europe - including coal, gas and nuclear. In 2009 the European market for wind turbines experienced a 23% growth rate, the same as the average growth rate over the last 15 years."Both in Europe and in the US, some 40% of all new power generating capacity installed in the past two years was wind energy. If the economic crisis continues, however, the reduction in power demand will start to impact wind energy, simply because of lower demand for new power plants. Nevertheless, the medium and long-term outlook remains very healthy, as political momentum is building towards a low carbon economy, without which humankind will not overcome three of the biggest concerns of our time - climate protection, energy security and the provision of jobs." "Wind power is a leader now, and will remain so in the future, attracting big investments and creating jobs. There is a boom waiting to happen in offshore wind energy. But, Europe's ageing electricity grids must be upgraded and extended, and the EU must also pursue a drive to build an offshore grid in the North and Baltic seas that will connect offshore wind farms to the shore, piping vast amounts of CO2-free energy to consumers at affordable prices."