In 1952, West Texas Utilities, Stockton, TX, helped pioneer power generation application of gas turbines with the installation of a Westinghouse model W81, rated at 5000 kW. That was followed by a second W81 in 1954 (possibly 1958 based on a second source). Both units were used in continuous (base load) operation and the exhaust heat from the second unit was used to heat feed water for a steam boiler at the site. In 1959, it was integrated with a fired boiler to form a "combined cycle" (gas and steam) power generating system.