Single-shaft Arrangement of CCP

In a single-shaft arrangement, it consists of one gas turbine, one steam turbine, one generator and one HRSG. The gas turbine and the steam turbine in this arrangement are coupled to a single generator in a tandem arrangement on a single shaft and thus, both of them drive the same generator in order to produce the required electricity.

With this arrangement, it has both advantages and disadvantages, which include:

• Advantage: save capital cost such as construction and equipment costs and space required to accommodate the extra generator and transformer.
• Disadvantage: limitated to concurrent operation of the gas turbine and steam turbine, unless the steam turbine can be decoupled from the generator through a clutch. In addition, during a fault in the generator, it will require the whole plant to cease operation in order to carry out the required maintenance work.

This disadvantage will be eliminated with the implementation of the Multi-shaft Arrangement of the combined cycle plants .