Solar Turbines Incorporated, a wholly owned subsidiary of Caterpillar Inc., designs and manufactures industrial gas turbines for onshore and offshore electrical power generation, for marine propulsion and for producing, processing and transporting natural gas and oil.
The company traces its history to the 1927 founding of the Prudden-San Diego Airplane Company, which became the Solar Aircraft Company in 1929. Through the Great Depression, they mainly produced components for other manufacturers, growing during World War II and diversifying into non-aircraft products after the war. During this period, they won a number of contracts to produce jet engine components. Convinced that the gas turbine was the prime mover of the future, the company invested heavily in the development of small turbines.
The turbine never came to be the main prime mover, but Solar's expertise in small turbines found a number of niche roles. The company was purchased by International Harvester Company in early 1960, becoming the Solar Division of International Harvester in 1963. In 1973, the Solar Division exited the aerospace industry to focus solely on industrial turbines. In 1975, the development and manufacture of the Solar Division's radial engines was moved into a newly formed Radial Engines Group, renamed the Turbomach Division in 1980.
Solar Turbines Incorporated became a wholly owned subsidiary of Caterpillar Tractor Co. after Caterpillar purchased the assets of the Solar Division and the Turbomach division from International Harvester on 31 May 1981. In 1985, Caterpillar sold the Turbomach Division to Sundstrand Corporation