When small-scale fuel cells, with about 5 kW capacity, first appeared in the late 1990s, they seemed made to order for electric cooperatives’ needs (see Figure A). Small, quiet, efficient, and clean, they held out a lot of promise not just as backup power sources, but also as primary power sources of electricity for residential customers near the ends of fast-growing, overburdened routes and in sparsely populated remote areas where extending the grid would be a costly endeavor.
The CRN Residential Fuel Cell Demonstration Program aimed to explore that potential. It operated prototype fuel cells, in residential settings (Figure B), in collaboration with electric cooperatives and with the U.S. Department of Defense, which was conducting a similar demonstration program at military bases and shared its information with CRN. The CRN program had these goals:
1. Evaluate the performance, durability, reliability, and maintainability of residential fuel cells.
2. Investigate the interaction of the fuel cells with the electric distribution grid and with the dispatch of electric energy.
3. Determine the suitability of key materials, designs, and components for utility and customer service.
4. Define and assess the related interface requirements for fuel, electricity, thermal recovery, and water and the associated installation costs.
5. Identify and refine promising applications for residential fuel cells, including planning for early-entry and mature markets. The results of the program are documented in this report. For more information about the demonstration program, see Section 1, Introduction.
For a discussion of the principles, characteristics, and operation of fuel cells, see Section 2, Technology Overview.
The demonstration clearly showed that fuel cells can function reliably and efficiently, and do not adversely affect the distribution grid. But the cost of the electricity they produce is very high: about 85¢/kWh at best for a future propane-fueled unit, versus about 9¢/kWh, on average, for grid-supplied electricity.
A major reason for this high cost is the high purchase price of fuel cells, which are highly complex systems comprising a fuel processor, electrochemical cell stack, dc to ac inverter, and storage batteries. A 5-kW unit today costs about $80,000. With design and manufacturing improvements, the price might drop to $30,000 by 2015.
To compound the cost problem, the price of fuel—natural gas or propane—is soaring.
It is much higher today than it was when residential fuel cells first appeared, and it is rising at a faster rate than grid electricity.
The combination of high purchase price, high fuel prices, and high maintenance costs make residential fuel cells an unattractive supplement or replacement for grid electricity.
For more information about the demonstration’s findings, see Section 3, Demonstration Results, and Section 5, Connecting to the Grid.