BMW develops steam-engine-inspired "Turbosteamer"

Using an innovative concept, BMW has succeeded in harnessing the biggest and as yet untapped source of energy in the car: Heat. Combining an innovative drive assist with a 1.8 liter BMW four-cylinder engine on the test rig reduced consumption by up to 15 percent while generating nearly 14 additional horsepower. At the same time, up to 15 lb-ft more torque was measured. This increased power and efficiency comes free of charge. The reason is that the energy is derived exclusively from the waste heat present in the exhaust gases and cooling system and doesn't cost you a single drop of fuel. The components for this drive system have been designed so that they are capable of being installed in existing model series. The long-term development goal is to have a system capable of volume production within ten years. (Recently, we reported that as much as 70 percent of the fuel burned up in car engines is dissipated as heat).


"¨"¨The Turbosteamer - as the project is known - is based on the principle of the steam engine: Fluid is heated to form steam in two circuits and this is used to power the engine. The primary energy supplier is the high-temperature circuit which uses exhaust heat from the internal combustion engine as an energy source via heat exchangers. More than 80 percent of the heat energy contained in the exhaust gases is recycled using this technology. The steam is then conducted directly into an expansion unit linked to the crankshaft of the internal combustion engine. Most of the remaining residual heat is absorbed by the cooling circuit of the engine, which acts as the second energy supply for the Turbosteamer. This innovative drive assist verifiably increases the efficiency of the combined drive system by up to 15 percent.

"The Turbosteamer reinforces our confidence that the internal combustion engine is undoubtedly a technology fit for the future,"? comments Professor Burkhard Göschel, Member of the Board of Management responsible for development and purchasing at BMW AG.