CHP Heat can be generated even in condensing power plants, when part of the steam passing through the turbine is extracted from the turbine before it reaches the last turbine stages and the condenser. District heat can be generated with the extracted steam in the same way as in district heating power plants, or the steam can be supplied to industrial purposes as shown in the following figure.

 
 

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Figure 4. Extraction Condensing Power Plant

 

The figure shows also a steam reduction station, which can be used, when the steam turbine is not available in order to secure process heat to the factory. Naturally, the process heat supplied through the steam reduction station is not CHP Heat according to the definition. Correspondingly, there is no electricity generation connected to the process steam going past the turbine through the steam reduction station and thus there is no corresponding CHP Electricity.

It is possible to operate the steam turbine and the steam reduction station simultaneously. In this case, a distinction has to be made concerning the part of steam going through the turbine and the part of steam going through the reduction station.

It is a common practice to construct steam reduction stations in all cogeneration power plants, where steam is used for CHP Heat supply.