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Your Mileage May Vary: White House Floats Proposal Requiring Auto Makers to Double Fuel Efficiency (JOSH MITCHELL And SHARON TERLEP, 6/27/11, WSJ)

The Obama administration may require auto makers to roughly double the average fuel economy of their car and light truck fleets from current levels to 56.2 miles per gallon by 2025.

White House officials outlined the plan to auto industry officials last week, said two people familiar with the matter, setting off a fight among auto makers, environmentalists and others.

Car makers say the proposal would effectively require most new vehicles sold in the U.S. to be battery-powered by 2025 and raise prices by thousands of dollars. Makers of electric vehicle technology say declining costs for lithium batteries will allow the auto industry to make big gains in fuel efficiency without stoking sticker shock.

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