NCPA - National Center for Policy Analysis

Rethinking Energy Efficiency and Conservation

August 13, 2001

The conventional wisdom is that we can conserve energy by using it more efficiently. But studies show that isn't true. In fact, when energy efficiency rises, energy consumption rises, too.

Take the greater efficiencies of combustion engines.

  • The best external combustion engines were about 20 percent efficient at the beginning of the 20th century -- but they achieved 40 percent efficiency at mid-century and are more than 50 percent efficient today.
  • Collectively, combustion engines burn about 80 percent of the thermal energy we use in the U.S. -- and the total amount of fuel they burn has risen right along with their efficiency.
  • The U.S. today consumes 100 quadrillion BTUs of thermal energy a year -- compared to 7 quads in 1910 and 35 quads in 1950.
  • A jet engine is now about as fuel-efficient as a car when payload delivered is considered -- since today's jets fly almost fully loaded, whereas cars are driven almost empty.

Source: Peter Huber (Manhattan Institute), "The Efficiency Paradox," Forbes, August 20, 2001.


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