how are solar cells built?
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The most common material used in solar cells is single crystal silicon. Solar cells made from single crystal silicon are currently limited to about 25% efficiency because they are most sensitive to infrared light, and radiation in this region of the electromagnetic spectrum is relatively low in energy.
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The process of making food in a plant from the sun's energy
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Solar cells convert the solar energy into elctricity and this electrical energy can be used for cooling
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(m)\n\nMake a solar cell in your kitchen\n\nWe found this article on http://www.scitoys.com/scitoys/scitoys/echem/echem2.html \n\nIt was super, super, super cool, so we thank them for allowing us to post it at TheSolarPlan.com!  This is nifty!\n\nA solar cell is a device for converting energy from the sun into electricity. The high-efficiency solar cells you can buy at Radio Shack and other stores are made from highly processed silicon, and require huge factories, high temperatures, vacuum equipment, and lots of money. \n\nIf we are willing to sacrifice efficiency for the ability to make our own solar cells in the kitchen out of materials from the neighborhood hardware store, we can demonstrate a working solar cell in about an hour. \n \nOur solar cell is made from cuprous oxide instead of silicon. Cuprous oxide is one of the first materials known to display the photoelectric effect, in which light causes electricity to flow in a material. \n\nThinking about how to explain the photoelectric effect is what led Albert Einstein to the Nobel prize for physics, and to the theory of relativity.\n\nMaterials you will need \n\nThe solar cell is made from these materials: \nA sheet of copper flashing from the hardware store. This normally costs about $5.00 per square foot. We will need about half a square foot. \nTwo alligator clip leads. \nA sensitive micro-ammeter that can read currents between 10 and 50 microamperes. Radio Shack sells small LCD multimeters that will do, but I used a small surplus meter with a needle. \nAn electric stove. My kitchen stove is gas, so I bought a small one-burner electric hotplate for about $25. The little 700 watt burners probably won't work -- mine is 1100 watts, so the burner gets red hot. \nA large clear plastic bottle off of which you can cut the top. I used a 2 liter spring water bottle. A large mouth glass jar will also work. \nTable salt. We will want a couple tablespoons of salt. \nTap water. \nSand paper or a wire brush on an electric drill. \nSheet metal shears for cutting the copper sheet. \n\n\n\n\n\n\nHow to build the solar cell \n\nMy burner looks like this: \n\nThe first step is to cut a piece of the copper sheeting that is about the size of the burner on the stove. Wash your hands so they don't have any grease or oil on them. Then wash the copper sheet with soap or cleanser to get any oil or grease off of it. Use the sandpaper or wire brush to thoroughly clean the copper sheeting, so that any sulphide or other light corrosion is removed. \n\nNext, place the cleaned and dried copper sheet on the burner and turn the burner to its highest setting. \n\nAs the copper starts to heat up, you will see beautiful oxidation patterns begin to form. Oranges, purples, and reds will cover the copper. \n\n\nAs the copper gets hotter, the colors are replaced with a black coating of cupric oxide. This is not the oxide we want, but it will flake off later, showing the reds, oranges, pinks, and purples of the cuprous oxide layer underneath. \n\n\n\nThe last bits of color disappear as the burner starts to glow red. \n\nWhen the burner is glowing red-hot, the sheet of copper will be coated with a black cupric oxide coat. Let it cook for a half an hour, so the black coating will be thick. This is important, since a thick coating will flake off nicely, while a thin coat will stay stuck to the copper. \n\n\nAfter the half hour of cooking, turn off the burner. Leave the hot copper on the burner to cool slowly. If you cool it too quickly, the black oxide will stay stuck to the copper. \n\nAs the copper cools, it shrinks. The black cupric oxide also shrinks. But they shrink at different rates, which makes the black cupric oxide flake off. \n\n\nThe little black flakes pop off the copper with enough force to make them fly a few inches. This means a little more cleaning effort around the stove, but it is fun to watch. \n\n\nWhen the copper has cooled to room temperature (this takes about 20 minutes), most of
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If you're talking about electricity generated from solar panels, it's not widely done because of how expensive it is to build and construct panels. The material (Germanium or Silicon) alone costs a lot to synthesize.\n\nWind power turns out to be a better alternative, if you consider the costs and benefits. Ocean-tide power may be good source of power too.\n\nNow look up "Dyson Sphere." This is another aspect of tapping solar power; Solar power tapped to the extreme, not for electricity, but for life; A solution for the evergrowing population of mankind. A Dyson Sphere is impossible to construct, but a few hundred years from now it may be possible to create a Dyson Belt, a collection of inhabitable planetoids built and placed in orbit 93 million miles from the sun (the same distance as the Earth).
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Light shining on a properly created solar cell. A solar cell can consist of an impure (doped) silicon (usually with phosphorus) with metal wire laid on top of it and then covered in glass (for protection, perhaps it might help build up the heat, but I'm not sure). When the light's energy hits the silicon, it knocks free electrons (from the phosphorus mostly) and then the wires will pick it up. Howstuffworks is a great site for this sort of question.
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the above one of solar cell is gr8\nor you can make a model of a wind mill, attach it to a motor and then, artificially, rotate it to produce current in the motor and connect it to a small bulb to show it lighting
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Photosynthesis is about 1% efficient while we can make PV cells about 20% efficient.\n\nThis is yet another case of nature being inferior to human technology.
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um solar panels? i dont know how they work though so i dunno.
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http://moskaluk.com/Mesh/solar_7.jpg\nMIKE
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There are many ways to take advantage of the energy produced by the sun.  A good place to start is with a passive solar energy water heater.  They are inexpensive to install and easy to maintain.  The simplest ones use the radiant energy of the sun and convert that to thermal energy using a material that absorbs the light instead of reflecting it, in layman's terms, something black.  \n\nPhotovoltaic (solar cell) systems convert sunlight directly into electricity. A solar or Photovoltaic cell consists of semiconducting material that absorbs the sunlight. The solar energy knocks electrons loose from their atoms in a semiconductor, allowing the electrons to flow through the material to produce electricity.\n\nFor a more in-depth explanation of photovoltaic technology try this site.
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You need the following:\n- Solar panel(s)\n- Batteries\n- Charging regulator\n- Low voltage cutoff\n\nThese last two will keep your battery from dying quickly.  They are often in the same device now.  Expensive, but much cheaper than new batteries every year (I had to learn the hard way on this one).  \nThe most difficult part is estimating how much battery/solar panel you need so you don't run out of electicity.  Also you need to match the solar panels to batteries.  It does not help to have a lot of battery capacity and a tiny panel or vice versa.  Most shops that sell these things can help you with this.
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Build a solar cell from a couple of thin sheets of copper and some salt water.  It requires a heat source, but with parental supervision it can be done by a 4th grader.  Easy!\n\n(see links below for how it's done)
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solar,  sun light, hydrogen
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Silicon solar cell efficiencies vary from 6% for amorphous silicon-based solar cells to 30% or higher with multiple-junction research lab cells. Solar cell energy conversion efficiencies for commercially available mc-Si solar cells are around 12%. The highest efficiency cells have not always been the most economical -- for example a 30% efficient multijunction cell based on exotic materials such as gallium arsenide or indium selenide and produced in low volume might well cost one hundred times as much as an 8% efficient amorphous silicon cell in mass production, while only delivering a little under four times the electrical power.
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Nuclear fusion is what you are talking about.  Basically smaller atoms (hydrogen for example) are smashed together under high energy to form larger atoms (helium for example).  In the process, a small amount of energy is given off.  This is the process that powers the sun, and if we could harness it, it would make a great source of electricity.  Anyway they have experimental fusion reactors, they just take in more energy then they give out making using them as a power source pointless.  They're working on that though.  Someday hopefully they can make a fusion reactor that gives off more energy then it takes in.
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I think you mean photovoltaic - photocells that generate a voltage when illuminated