(“The Effency Dilemma” by David Owen, The New Yorker, 12/20-27/2010)
Save the environment by driving a Prius, right? Surprisingly, not as much as people think. With the greater fuel efficiency, owners feel justified in driving more, such as 10 miles to pick up a jar of mustard. Last year, the Secretary of Energy stated that the federal new car standards for efficiency will save 1.8 billion barrels of oil. But the problem is not that simple, as any Secretary of Energy should know.
Lets save the environment by switching from incandescent bulbs to compact fluorescents, another mandate of our government. But with the efficient new bulbs, we leave lights on throughout the house in the evening. (In our early East Lansdowne house, the electric supply was so limited we could not turn on the upstairs bedroom lights until all the downstairs lights were turned off.) An economist once calculated that an ancient Babylonian had to work some 41 hours for enough oil to provide the light equivalent to a 75-watt incandescent bulb for one hour. Thomas Jefferson only had to work five and a half hours for the same light from a tallow candle. Compact fluorescents now do that for a half a second of work. Has any of these improvements decreased our energy consumption? Au contraire, Fred Astaire. We now consume energy so extravagantly, astronomers have trouble finding darkness anywhere on the planet.
A few years ago, my wife and I bought a new refrigerator significantly more efficient than our old one. But where did the old one go? Down in the basement where it lives on, still consuming electricity. Even worse, food stored down there tends to be forgotten and eventually has to be thrown out.
This problem of the elusive benefits of energy efficiency is called “the Jevons effect” from a book written in 1865 by an English economist, William Stanley Jevons. England was in the middle of the Industrial Revolution and was concerned about their dwindling coal supply, used largely to produce iron. They were hoping efficiencies in the smelting process would prolong the supply, but Jevons pointed out that the efficiencies would make iron cheaper, increasing its use and requiring more coal, not less. He concluded, in italics, “It is wholly a confusion of ideas to suppose that the economical use of fuel is equivalent to a diminished consumption. The very contrary is the truth.”