Fox News is promoting a Wall Street Journal column by Bjorn Lomborg to claim that electric vehicles are “even worse” for the environment than conventional gasoline cars. But experts say Lomborg's assumptions are out of step with reality and that the environmental benefits of electric vehicles will only grow in the near-future.

Lomborg, a prominent critic of environmentalists, claimed that because producing an electric car is more carbon-intensive, it could produce more carbon dioxide over its lifetime than a conventional car, citing a study published in the Journal of Industrial Ecology:

If a typical electric car is driven 50,000 miles over its lifetime, the huge initial emissions from its manufacture means the car will actually have put more carbon-dioxide in the atmosphere than a similar-size gasoline-powered car driven the same number of miles.

Fox News hosted Lomborg on Wednesday to expose what it called the “dirty little secret” of electric vehicles. Seizing on Lomborg's figures, Fox Business' Stuart Varney claimed that “the battery powered cars are just as bad for the environment as your average sedan -- even worse!” And Fox Business host Gerri Willis suggested electric cars are not “contributing less to global warming” than conventional cars:

But Lomborg's assumption of a 50,000 mile lifetime “seems too low,” according to University of California at Los Angeles' Dr. Deepak Rajagopal, an environmental economist who focuses on life cycle assessments. Indeed, the study Lomborg cites “assumes almost twice that lifetime,” according to co-author Guillaume Majeau-Bettez. It estimates a 20-24 percent reduction in emissions from electric vehicles driven 90,000 miles and powered by average European electricity. The Chevy Volt and the Nissan Leaf, the two most popular electric cars in the U.S., both have 100,000 mile battery warranties.

And as the Natural Resources Defense Council's Max Baumherner noted, the study used estimates for production emissions that are three times higher than those from Argonne National Laboratory, which perhaps explains why other studies have found greater environmental benefits from electric cars. A life-cycle analysis overseen by Dr. Rajagopal found that battery-electric vehicles (BEV) powered by California's electricity mix produce significantly fewer emissions compared to conventional vehicles (CV):

Majeau-Bettez told Media Matters that because “the electric car industry is still in its infancy, it is reasonable to expect improvements in the future.” Guardian journalist Leo Hickman echoed this point, noting that electric cars “will only increase their environmental credentials” as they reach mass production:

The problem for electric cars is that they will only increase their environmental credentials (compared to “conventional” cars) once more and more of them are made and used, which, in itself, will drive faster and deeper innovation in battery technology, production efficiencies and end-of-life recyclability. It's somewhat unfair to compare them to conventional cars at present because they are an immature, fledgling technology, but the opportunity for increased efficiency throughout their lifecycle seems significant as/if they become more popular.

Electric cars will also become more environmentally friendly as the electricity they run on becomes cleaner. Meanwhile, as Dr. Rajagopal told Media Matters, “gasoline is getting dirtier because of the transition to lower-grade resources,” like tar sands.