Renewable energy
They do not harm the environment. Using
renewable energy you can save your money
and protect the environment.
References
http://worldnuclear.org/info/EnergyandEnvironment/RenewableEnergyandEle
http://environment.nationalgeographic.com/environment/globalwarming/windpow
http://environment.nationalgeographic.com/environment/globalwarming/solarpow
http://environment.nationalgeographic.com/environment/globalwarming/hydropo
http://environment.nationalgeographic.com/environment/globalwarming/geotherm
http://education.nationalgeographic.com/education/encyclopedia/renewableenergy
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