an internal combustion engine which works on a gas fuel, such as natural and petroleum by-product gases, liquefied gas (butane-propane mixture), blast-furnace gases, and generator gases. Advantages of a gas engine over liquid fuel engines include considerably less wear on basic parts because of the more complete mixture formation and combustion, the absence of noxious impurities in exhaust gases, and the possibility of using a higher compression ratio than with gasoline-run engines. Modern stationary gas engines achieve 42 percent efficiency. The most commonly used gas engines are those that work on the diesel cycle. Gas engines rated at 12,000 kilowatts (16,000 horsepower) are used as power sources in various branches of the national economy, especially in the gas and oil industry to drive gas pumping installations.
Gas engines that operate on liquefied gas (gas-liquid engines) are used where it is important to render exhaust gases harmless and smokeless, for example, for city buses or during the operation of cars, lift loaders, and trucks in warehouses and underground locations.
K. I. GENKIN