Mitsubishi Heavy Industries is set to begin developing the basic technologies for a triple combined cycle power generation system integrating solid oxide fuel cells (SOFC) and a gas turbine combined cycle power generation system. Under the umbrella of Japan’s New Energy and Industrial Technology Development Organisation (NEDO), the company will launch a two-year study this year as part of a project entitled “Development of Systems and Basic Technologies for Solid Oxide Fuel Cells (SOFC)” a project that has been started up after a proposal from MHI.

In a triple combined cycle power generation system, an SOFC power generation system is placed before the GTCC. By generating power at three stages – the fuel cell, gas turbine, and steam turbine – the resulting fuel cell combined cycle (FCCC) system achieves extremely high efficiency in generating power from natural gas. The FCCC system is expected to achieve a new world high in such an efficiency, exceeding 70% (low heating value)1 for several hundred MW class power generation and over 60% (LHV) efficiency for several tens MW class power generation.

As part of the study, MHI will develop the basic technologies needed to combine SOFC and gas turbine power generation systems. For the SOFC system, the company will test the system’s characteristic features and durability under high pressure (up to 3.0 MPa). Issues to be considered for the gas turbine system include conversion of gas turbines and combustor development. MHI also plans to demonstrate a power generation simulation involving SOFC and a gas turbine system working in conjunction.

MHI sees FCCC triple combined cycle power generation as a revolutionary technology that will result in 10% to 20% improvements in power generation efficiency over existing natural gas-fired power generation systems. The company plans to pursue development based on the results of the basic technologies study, with the ultimate goal of commercialising the technology.