During a July 17 American Council on Renewable Energy forum, General Motors’ manager of vehicle fuels and advanced technology said that petroleum’s role as the dominant source of transportation fuel is coming to an end as vehicle manufacturers begin to embrace alternative fuel vehicles. He said that the company is focusing on fuel efficiency improvements for traditional vehicles as well as biofuels. The same day during a House Energy and Commerce Subcommittee on Energy and Power, Howard Gruenspecht, the deputy administrator of the Energy Information Administration, said that petroleum products provided about 93 percent of total transportation energy in 2010, with gasoline accounting for 92 percent of passenger cars and light-duty trucks.