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Old 10-11-2019, 02:24 AM   #7410 (permalink)
redpoint5
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Join Date: Aug 2010
Location: Oregon
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Quote:
Originally Posted by litesong View Post
A book co-edited by Thomas Homer-Dixon contained a passage stating that windmills "might never generate as much energy as was invested in building [them]."
Quote:
The concept of net energy must be applied to renewable sources of energy, such as windmills and photovoltaics. A two-megawatt windmill contains 260 tonnes of steel requiring 170 tonnes of coking coal and 300 tonnes of iron ore, all mined, transported and produced by hydrocarbons. The question is: how long must a windmill generate energy before it creates more energy than it took to build it? At a good wind site, the energy payback day could be in three years or less; in a poor location, energy payback may be never. That is, a windmill could spin until it falls apart and never generate as much energy as was invested in building it.
-David Hughes, Carbon Shift

https://www.snopes.com/fact-check/wind-idiot-power/

Got anything else, preferably taken in context?
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