same change in pressure) of the gas Tesla turbine is estimated to be above 60%. The turbine efficiency is different from the cycle efficiency of the engine using the turbine. Axial turbines that operate today in steam plants or jet engines have efficiencies of over 90%. This is different from the cycle efficiencies of the plant or engine, which are between approximately 25% and 42%, and are limited by any irreversibility to be below the Carnot cycle efficiency. Tesla claimed that a steam version of his device would achieve around 95% efficiency. The thermodynamic efficiency is a measure of how well it performs compared to an isentropic case. It is the ratio of the ideal to the actual work input/output. In the 1950s, Warren Rice attempted to recreate Tesla's experiments, but he did not perform these early tests on a pump built strictly in line with Tesla's patented design (it, among other things, was not a Tesla multiple staged turbine nor did it possess Tesla's nozzle). Rice's experimental single-stage system's working fluid was air. Rice's test turbines, as published in early reports, produced an overall measured efficiency of 36–41% for a single stage. Higher efficiency would be expected if designed as originally proposed by Tesla. In his final work with the Tesla turbine and published just before his retirement, Rice conducted a bulk-parameter analysis of model laminar flow in multiple disk turbines. A very high claim for rotor efficiency (as opposed to overall device efficiency) for this design was published in 1991 titled "Tesla Turbomachinery". This paper states: Modern multiple-stage bladed turbines typically reach 60–70% efficiency, while large steam turbines often show turbine efficiency of over 90% in practice. Volute rotor-matched Tesla-type machines of reasonable size with common fluids (steam, gas, and water) would also be expected to show efficiencies in the vicinity of 60–70% and possibly higher. Applications Tesla's patents state that the device was intended for the use of fluids as motive agents, as distinguished from the propulsion or compression of fluids (though it can also be used for those purposes). As of 2016, the Tesla turbine has not seen widespread commercial use. The Tesla pump, however, has been commercially available since 1982 and is used to pump fluids that are abrasive, viscous, shear sensitive, contain solids, or are otherwise difficult to handle with other pumps. Tesla himself did not procure a large contract for production. The main