The
Energy Information Administration reports that it took only 7.32 thousand BTUs of energy to produce each dollar of real GDP in 2011, making last year's economy the most energy-efficient in history (see chart). Energy consumption per dollar of output in 2011 was 2% less than 2010 (7.47 thousands BTUs), and half of the energy required in 1979 (14.79 thousand BTUs).
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