Power Generation

Combined Heat and Power (CHP)

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Combined Heat and Power (CHP), also known as Cogeneration, is an efficient process used to simultaneously generate electricity and heat.

Often a steam turbine is used to generate electricity and the remaining heat is used for district heating or process heat requirements. However the heat and electricity demand is seldom constant, so being able to vary the proportion of heat to electricity generated can be a massive advantage. This can be done by extracting steam from different stages of the steam turbine, however this reduces the turbine efficiency. Completely disconnecting one of the steam turbine stages with an SSS Clutch offers the greatest flexibility (see schematic below).

By using the SSS Clutch, the plant can optimise the heat storage system, making it more cost effective and turning the CHP system into a dispatchable generating plant providing variable power whilst maximising machine utilisation. This type of CHP system with an SSS Clutch is also ideallly suited for Small Modular Reactors (SMR) which are best run at constant energy output.

Reference sites

  • 88 machines in 18 countries transmitting 4.6GW
  • Clutch power rated from 320kW to 170MW
  • Clutch speed from 1500rpm to 9040rpm