Ronald Bailey ponders the rebound effect, the phenomenon where increased energy efficiency is offset by increased use. For example:
[L]ighting efficiency has improved by more than many thousand-fold from sputtering candles to modern LEDs over the past three centuries. The result of this vast improvement in lighting technologies, writes Jeffery Tsao from the Sandia National Laboratory and his colleagues, "has been an increase in demand for energy used for lighting that nearly exactly offsets the efficiency gains." They note, "When lighting become cheaper, economic agents become very creative in devising new ways to use it." In fact, they predict that as lighting efficiency improves, say, with LED lighting, over the coming decades that the increased demand for lighting will again likely swamp any gains in energy efficiency.
He concludes that "energy efficiency mandates advocated by environmental activists with the aim of mitigating future man-made global warming will likely fall far short of their goals." Earlier Dish on the rebound effect here and here.
The Dish 