Current State and Future Prospects of Industrial On-Site Fuel Cell Systems

The current state, problems for practical use, and future prospects of industrial on-site fuel cell systems based on fuel cells of the several hundred kilo-watt class such as phosphoric acid fuel cells (PAFCs), molten carbonate fuel cells (MCFCs), and solid oxide fuel cells (SOFCs) are summarized. A 200kW multi-fuel-type PAFC system, 250kW MCFC co-generation system, 300-kW-class MCFC-micro-gas-turbine hybrid system, 100-kW-class SOFC co-generation system, and 220kW SOFC-micro-gas-turbine hybrid system are investigated as examples of industrial one-site fuel cell systems. High efficiency in power generation and reductions of system and running costs are important prerequisites for the widespread use of industrial on-site fuel cell systems. The technology of PAFCs is already mature. However, their application is restricted by high system costs and low efficiency in power generation. Systems which are expected to find application in food factories, hotels, sewerage sites, and chemical factories are those that run on free fuel, such as biogas, digester gas, exhaust fuel (i.e. exhaust methanol), and byproduct hydrogen. Systems based on MCFCs and SOFCs are currently under development. They will enter widespread use in factories and other buildings in the near future because of their high efficiency in power generation.