Policy debate hypes wasteful side of hybrid cars

UC DAVIS (US) — The argument that people who have fuel-efficient cars drive them more—and therefore use more energy—is overplayed and inaccurate, economists say.

Critics of energy efficiency programs in public policy debates have cited the “rebound effect” as a reason that hybrid cars and plug-in electric vehicles don’t really save energy in the long run.

The “backfire” concept, a more extreme version of rebound, actually stems from a 19th-century analysis in a book titled The Coal Question by Stanley Jevons. The book hypothesized that energy use rises as industry becomes more efficient because people produce and consume more goods.  But economists say that in the modern economy, the effect is not supported empirically.


“If a technology is cheaper to run, people may use it more. If they don’t, they can use their savings to buy other things that required energy to make. But evidence points to these effects being small—too small to erase energy savings from energy efficiency standards, for example,” says David S. Rapson, assistant professor of economics at University of California, Davis.

Rebound effects are therefore “no excuse for inaction,” Rapson and colleagues write in a comment article in the journal Nature.

Energy efficiency standards will once again be a topic of debate—and a potential target for attack—with the renewed focus on climate change and the possibility of federal regulatory action, Rapson says.

“From an economic perspective, a carbon tax or well-functioning cap-and-trade market is still optimal. But if the political reality doesn’t allow these, efficiency standards should be evaluated based on the balance of costs and benefits. Rebounds are an important consideration, but are often overblown and misunderstood.

“Even though increased efficiency may prompt changes in behavior, energy is still saved overall,” Rapson says. “Energy efficiency policies should therefore continue to be considered as a way to address greenhouse gas emissions.”

Researchers from Yale University and the Environmental Defense Fund in New York contributed to the study.

Source: UC Davis