Keep in mind that turbine efficiency is different from the cycle efficiency of the engine using the turbine. Axial turbines which operate today in steam plants or jet engines have efficiencies of about 60–70% (Siemens Turbines Data).[citation needed] This is different from the cycle efficiencies of the plant or engine which are between approximately 25% and 42%, and are limited by any irreversibilities to be below the Carnot cycle efficiency. Tesla claimed that a steam version of his device would achieve around 95 percent efficiency.[12][13] Actual tests of a Tesla Steam Turbine at the Westinghouse works showed a steam rate of 38 pounds per horsepower-hour, corresponding to a turbine efficiency in the range of 20%, while contemporary steam turbines could often achieve turbine efficiencies of well over 50%.