China and US cooperation in promoting such vehicles is a concrete step against global warming. But how to measure claims in miles "per gallon"?
But they are cooperating on at least one thing – rapid acceleration in the production of electric and hybrid vehicles.
During his trip to the climate-change conference, President Obama can point to his recent pact with Beijing to jointly share information on standards, research, and demonstration of such vehicles. That should help make up for his dashed hopes that Congress would have set targets for cutting carbon emissions by now.
Mr. Obama is banking heavily on electric and hybrid cars to reshape the world's energy future. Earlier this year, he promised to "put one million plug-in hybrid vehicles on America's roads by 2015." But besides the new cooperation with China and the billions in subsidies to bolster this small industry, his main policy tool is to push automakers to produce fleets that run with an average 35.5 miles per gallon by 2016.
The industry, sensing the heat, is also counting on electrics and hybrids as part of their future. Last summer two automakers conducted a brief bragging battle over whose triple-digit mileage figure for its future electric car is higher. General Motors put its long-ballyhooed Volt at 230 miles per gallon. Nissan countered that its new Leaf would get 367 m.p.g. Both are expected in showrooms in 2010.
But all the m.p.g. talk at this stage is a little silly. No standard exists for measuring the "gas mileage" of plug-in vehicles that run on electricity. The Volt, for example, actually has two propulsion systems, an electric motor powered by rechargeable batteries and a gasoline engine. It begins using gasoline after about 40 miles of driving on batteries alone. How much gasoline a driver would use could vary widely, depending on how many trips over 40 miles in distance a driver took.