Earth Protect Blog

China and US cooperation in promoting such vehicles is a concrete step against global warming. But how to measure claims in miles "per gallon"? As the two largest carbon polluters, China and the US have yet to agree on much before the international conference on global warming in Copenhagen next week.

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.

Nissan's Leaf won't use gasoline at all, so in terms of gasoline used, the mileage will be, well, infinite.

Both cars will recharge their batteries from the electric grid, introducing more complications. The cost of electricity varies by locale and sometimes by the time of day. It could be generated by a coal-fired power plant (bad for planet-heating carbon emissions) or renewable wind or solar energy.

The Environmental Protection Agency is far from ready to apply mileage figures to either vehicle. The EPA will need a new system for measuring fuel economy, perhaps using two figures, one estimate for gasoline used per mile and the other for electricity per mile. Or perhaps it will assign a single number based on the estimated total cost of fuel per mile driven.

Either new car is likely to be several times more efficient than the current m.p.g. king of the road, the Toyota Prius. It gets a mere 50 m.p.g. and can't be plugged into the electric grid.

Will the Volt and Leaf even be affordable?
Speculation puts the Volt at $40,000 to $45,000 and the Leaf at $25,000 to $40,000, though a $7,500 government rebate could reduce those figures considerably. A 2010 Toyota Prius costs as little as $22,000.

While Toyota remains leery of all-electric cars, other Japanese automakers are committed to bringing them to market. Malls in Japan will be putting in charging stations. Meanwhile, China's top automakers are conducting joint R&D to turn out state-of-the-art electric vehicles. India's Reva carmaker wants in the game too. At the recent auto show, Renault CEO Carlos Ghosn said he expects electric cars to grab 10 percent of the worldwide market for all vehicles by 2020.

The electric car has been jolted back to life and could become the kind of technological solution to climate change that many nations can agree on. Even if Copenhagen fails to set global goals on overall carbon reduction, at least such a concrete step in reducing vehicle pollution is already being taken.