The Effective-use Method of Exhaust Heat for Distributed Fuel Cells

Abstract

When a proton exchange membrane fuel cell cogeneration system with a town gas reformer is distributed to each building and energy is supplied, the transportation loss of the heat supply is small. However, if the fuel cell system is installed in each building, a drop in energy efficiency is predicted due to the imbalance between the rate of heat supply and electric power supply. Although the installation of a battery and a heat storage tank is effective, using these methods, the system and the operational plan become complicated, and serve to raise the equipment costs. In this study, the fuel system (the hydrogen piping network), the electric power system (the power line network), and the heat-power system (the hot water piping network) of the fuel cells installed in each building are connected, and the best method of satisfying two or more of electric power and heat loads of the buildings in cooperation is examined. When two or more fuel cells are connected in a network, then the method of cooperation and control of the electric power output and the heat power output is called a fuel-cell-energy-network (FEN) in this chapter. In an FEN, it is possible to stop a fuel cell, which represents the operational status of a partial load with low efficiency in the cooperative operational control by FEN, to utilize the electric power generated by other fuel cells and to improve the efficiency of the system as a whole.