UNITED KINGDOM - JUNE 07: The street lamp stands alone requiring no electrical cable outside the National Energy Centre, Milton Keynes, Buckinghamshire. The turbine charges the battery which runs the lamp's 20 Watt bulb. The National Energy Foundation was set up in 1990 to help UK energy consumers understand the efficiency and value that can be achieved by installing energy saving devices and implementing appropriate renewable energy sources in homes, schools and offices. (Photo by SSPL/Getty Images)
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