Next-Generation Fuel Cell Power Generating System Initiatives
An integrated power generating system comprising SOFC + gas turbines + steam turbines shows promise for high-efficiency power generation as future replacement for thermal power plants in future large-scale projects.
However, considering the limitations of the SOFC mass production in the initial stages of market adoption, we will first focus on developing the market with small-to-medium-sized systems. As a measure to improve the efficiency of existing gas turbine combined cycle generating equipment in addition to co-generation for medium-sized power supply, we are examining ways to accelerate adoption, including topping improvements that involve partially expanding small-capacity SOFC facilities in relation to their gas turbine capacity.
A transmission end-power generation efficiency of more than 70 percent (lower heating value, LHV) can be expected from a future natural gas-fired 100-megawatt-class SOFC + gas turbine + steam turbine combined-cycle system (gas turbine fuel cell combined cycle, or GTFC, Figure 1), which is positioned as a future replacement for large-scale thermal power plants. This will enable carbon dioxide (CO2) emissions from thermal power stations to be reduced by around 20%. Even when coal is used as fuel, a transmission end-power generation efficiency of more than 60 percent (LHV) can be expected in 100-megawatt-class integrated coal gasification + SOFC + gas turbine + steam turbine combined-cycle systems (integrated coal gasification fuel cell combined cycle, or IGFC, Figure 2), and similarly, this would allow CO2 emissions to be reduced by around 30%.
Mitsubishi Power will lead the technological development of fuel cells and aim to achieve even higher capacity and efficiency gains, culminating in the development of actual systems for utility use.
Figure 1: Gas Turbine Fuel Cell Combined-cycle Power Plant
Figure 2: Coal Gasification Fuel Cell Combined-cycle Power Plant