Combined cycle success

has successfully tested a combined-cycle power generation system incorporating solid oxide fuel cells (SOFC) and a micro gas turbine (MGT), a first in

.

MHI has been developing the system since 2004, and the recent testing verified 75kW of power generation by the system at the company's Nagasaki Shipyard & Machinery Works. MHI now aims to start production of a 200kW combined-cycle power generation system this October. The company will then continue developing systems with larger capacities and higher efficiency to eventually develop a system suitable for utility applications.

The SOFC is a ceramic-based fuel cell that directly produces electricity by chemical reaction between oxygen in the air and hydrogen removed from city gas through reforming. The SOFC-MGT combined-cycle power generation system uses unreacted hydrogen contained in the city gas exhausted from the SOFC and hot air also discharged from the SOFC. The gas and air from the SOFC are used to drive an MGT to generate electricity.

This two-stage power generation system achieved power generation efficiency above 50 per cent, significantly higher than conventional power generation systems. MHI said large-scale SOFC combined-cycle power generation system could help reduce CO₂ emissions, alongside nuclear power generation and high-efficiency utility-use thermal power generation systems.