General Motors announced plans Wednesday to produce a new Chevy Impala sedan powered by both gasoline and natural gas.
The new Impala will likely go on sale next summer as part of the 2015 model year, GM said. It will be equipped with both a traditional gas tank and a separate compressed natural gas tank mounted in the trunk.
Drivers will have the ability to toggle between fuels, with total range expected to be "up to 500 miles."
The new Impala will join a number of natural-gas-consuming vehicles already on the market, including the Honda Civic, the Chevy Silverado and the GMC Sierra 2500. The vehicles attempt to take advantage of the U.S. shale gas boom unleashed by hydraulic fracturing, or fracking.
Fracking -- a process for extracting fuel by injecting pressurized water and chemicals into the ground -- has drawn concern from environmentalists who warn that it can pollute water supplies and generate toxic waste products. But natural gas has the advantage of burning cleaner than gasoline, producing few greenhouse gas emissions.
"We know that U.S. energy security won't come from a one-off moonshot," GM CEO Dan Akerson said in a speech at a conference in Washington. "It will flow from our systematic investment in technology and innovation .... and it will be assured by fully and safely exploiting our shale gas reserves."
Akerson cautioned that initial sales of the bi-fuel Impala will be modest, with its customer base consisting mostly of commercial and government fleets.
"[S]elling 750 to 1,000 units in the first model year would be a home run," Akerson said.
A big hurdle for bi-fuel vehicles is the scarcity of compressed-natural-gas stations in the U.S. There are about 1,200 nationwide, only half of which are open to the public, Akerson said, compared with over 168,000 retail gasoline stations.