Rebound effect, back in the news
An article in the New Yorker raises, yet again, the question of whether energy efficiency actually saves energy or promotes more consumption. This issue comes up periodically, but proponents of this idea never seem to be able to prove their case, and there’s a reason for that: it doesn’t make sense. David Goldstein of NRDC has a cogent refutation of the errors of logic in the New Yorker article here.
Here’s my letter to the New Yorker, just submitted this morning.
To the Editor:
David Owen’s article “The Efficiency Dilemma”, in the New Yorker (Dec. 20/27, 2010) conflates two distinct effects: the rebound effect (people who buy a more efficient device use it more and so “take back” some of the energy savings because it’s cheaper to operate that device) and the wealth effect (society gets richer so consumers buy more goods and services).
Measurements of the true rebound effect almost universally show that the effect is either zero (for devices like cable boxes, where user behavior doesn’t affect energy consumption much) or small (like for automobiles). So proponents have focused more recently on the macroeconomic effects related to wealth. They have argued that energy efficiency alone has caused folks to buy bigger homes, more appliances, and more household goods, but there’s no convincing evidence for that hypothesis. Instead, it's technology improvements, productivity gains, market structure changes, and general wealth increases that are the major contributors to the overall rise in consumption.
By all means let’s properly account for the rebound effect when it exists, but let’s not perpetuate the myth that increasing energy efficiency leads to more energy consumption than otherwise. That’s just wrong, and the data prove it.
Jonathan Koomey, Ph.D.
Consulting Professor, Stanford University
More on this issue as it develops.
