<Li> Pressure compound multi-stage impulse, or "Rateau", after its French inventor, Auguste Rateau . The Rateau employs simple impulse rotors separated by a nozzle diaphragm . The diaphragm is essentially a partition wall in the turbine with a series of tunnels cut into it, funnel shaped with the broad end facing the previous stage and the narrow the next they are also angled to direct the steam jets onto the impulse rotor . </Li> <Li> Mercury vapour turbines used mercury as the working fluid, to improve the efficiency of fossil - fuelled generating stations . Although a few power plants were built with combined mercury vapour and conventional steam turbines, the toxicity of the metal mercury was quickly apparent . </Li> <Li> Screw turbine is a water turbine which uses the principle of the Archimedean screw to convert the potential energy of water on an upstream level into kinetic energy . </Li> <Table> <Tr> <Td> </Td> <Td> This section relies largely or entirely on a single source . Relevant discussion may be found on the talk page . Please help improve this article by introducing citations to additional sources . (May 2018) </Td> </Tr> </Table>

Reaction turbine has more hydraulic efficiency than impulse turbine