Advanced Combustion Engines

Although internal combustion engines have been used for more than a century, significant improvements in energy efficiency and emissions reduction are still possible. Because of their relatively low cost, high performance, and ability to use renewable fuels (e.g. ethanol and biodiesel), conventional vehicles with combustion engines will likely dominate the market for at least the next 20 years. The United States can cut its transportation fuel use 20%–40% through commercialization of advanced engines—resulting in greater economic, environmental, and energy security. As hybrids and plug-in hybrids become cost competitive and gain market share, employing advanced combustion engines in these vehicles will enable even greater fuel savings.

The Advanced Combustion Engine R&D subprogram of the U.S. Department of Energy's Vehicle Technologies Program (VTP) is improving the fuel economy of passenger vehicles (cars and light trucks) and commercial vehicles (medium-duty and commercial trucks) by increasing the efficiency of the engines that power them. Work is done in collaboration with industry, national laboratories, and universities, as well as in conjunction with the FreedomCAR and Fuels Partnership for passenger vehicle applications and the 21st Century Truck Partnership for commercial vehicle applications.