Dear Twig: How does [active] solar energy work?
It works through devices called photovoltaic (“foe-toe-vole-TAY-ik”) cells. Photovoltaic, or PV, cells turn energy from sunlight into electricity. The stuff they get made from — special materials called semiconductors — lets them do it. Seen from the side, PV cells look like wafers: thin, flat, with several layers.
A single tiny PV cell can run a watch or a calculator. Lots of PV cells rigged together — into a solar module, or solar panel — can power, say, a phone or a satellite. Lots of panels hooked together can help juice a home, a school or a city.
What’s cool? Solar energy makes no pollution. And the fuel for it, sunlight, comes to us free. (Unlike fuels like coal and oil.) Less cool? The panels, etc., cost a fair bit o’ money.
Today more people use solar energy. And more want to know more about it. A man named Bill Spratley, who heads a group called Green Energy Ohio, says, “This is a technology whose time has come.”
Twig
P.S. Green Energy Ohio: http://www.greenenergyohio.org. Try the “Clean Power Estimator”!
Note: Active solar energy refers to the transformation of sunlight to generate electricity. Passive solar energy means the direct use of sunlight to heat and light buildings (at least in part). Sources included the U.S. Department of Energy, http://www1.eere.energy.gov/solar/photovoltaics.html; NASA, http://science.nasa.gov/headlines/y2002/solarcells.htm; the Ohio Department of Development, http://www.odod.state.oh.us/cdd/oee/RE_solar.htm; and Green Energy Ohio (GEO), http://www.greenenergyohio.org. Bill Spratley, GEO executive director, recently spoke in Wooster.
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“Smart Stuff with Twig Walkingstick,” a service of The Ohio State University College of Food, Agricultural, and Environmental Sciences — specifically, of the Ohio Agricultural Research and Development Center (OARDC) and Ohio State University Extension, both part of the College — is a weekly column for children about science, nature, farming and the environment. For details and to receive Twig free by mail, e-mail or fax, contact Kurt Knebusch, News and Media Relations, CommTech, OSU/OARDC,1680 Madison Ave., Wooster, OH 44691, knebusch.1@osu.edu, (330) 263-3776. Available online at extension.osu.edu/~news/archive.php?series=science.
