Supercharged gas turbine combined cycle: an improvement in plant flexibility and efficiency

This paper shows an innovative combined cycle solution that allows to increase the plant operational flexibility improving, at the same time, its global efficiency in part-load operation. In fact, nowadays, the necessity to maintain a high plant performance in prospect to fluctuating energy demand from electric grid has become a very critical problem in the energy sector. The solution here presented is characterized by a supercharged gas turbine, with an innovative control strategy, integrated in a conventional NGCC (natural gas combined cycle). This proposed solution, called SNGCC (supercharged conventional natural gas combined cycle), with an additional compressor stage upstream of the GT (gas turbine) cycle, has allowed to achieve, during part-load operation, significantly higher efficiency respect to conventional natural gas combined cycle. Consequently, also the possible operation range is extended.