General Motors will build a Chevrolet Impala sedan for retail and fleet customers that operates on either gasoline or compressed natural gas (CNG), GM Chairman and CEO Dan Akerson recently announced.

Expected to go on sale next summer as a 2015 model, Akerson unveiled the car during remarks at an energy summit marking the 40th anniversary of the OPEC Oil Embargo, an event attended by political, business and military leaders to assess the current state of America’s oil dependence since the 1973 oil embargo.

Akerson said the bi-fuel Impala is an example of using affordable technology to reduce oil consumption and save consumers money at the pump.

“We know that U.S. energy security won’t come from a one-off moonshot,” Akerson said. “It will flow from our systematic investment in technology and innovation... our drive to get more from existing energy sources and renewables... our commitment to conservation... and it will be assured by fully and safely exploiting our shale gas reserves.”

According to Akerson, the Chevrolet Impala bi-fuel sedan will addresses the range-anxiety issue associated with vehicles that run only on natural gas. It features a factory-engineered and fully warranted powertrain that switches seamlessly from CNG to gasoline. Total range is expected to be up to 500 miles.

Akerson said that in addition to advanced technologies and alternative fuels, achieving energy security will require productive partnerships between energy companies, utilities, environmental groups, labor unions, universities and manufacturers. GM, he said, is working closely with 14 of the country’s largest unions and environmental groups through the Blue-Green Alliance, and has relationships with regulators that are “more constructive than ever.”

Akerson also reiterated a call he made earlier this year for the Administration and Congress to create a new, consumer-driven national energy policy from a position of strength and abundance. For its part, GM is committed to saving 12 billion gallons of gasoline in its 2011 to 2017 model year vehicles — offsetting nearly a year of crude imports from the Persian Gulf — with technologies that include lighter materials to reduce vehicle mass, alternative fuels, clean diesel, and electrification.