A space-age energy source is splashing down on earth.
A spinoff of the fuel cells that were first used on the Gemini and Apollo space missions as well as on the Columbia space shuttle are about to be tested terrestrially for possible commercial use.
Considerable difference exists between the fuel cells employed by the National Aeronautics and Space Administration (NASA) and those which soon will be supplying two utilities, one on each coast, with power. That difference in design is one reason why it has taken many years for commercial fuel cells to evolve into a viable energy alternative.
The fuel cells used in space capsules are designed for compactness and energy efficiency with little regard for the price tag.
The result is a bread-box-sized fuel cell that runs on pure oxygen and pure hydrogen and is capable of putting out 8 to 10 kilowatts of power under normal operating conditions.
Commercial fuel cells, on the other hand, are the size of a walk-in cooler and work on air and fossil fuels from which oxygen and hydrogen are drawn.
The fuel cell is basically an enormous battery that can run on various fuels and produces electricity without combustion. After the hydrogen is produced in a catalytic reaction it is combined with oxygen to produce heat, steam, and most important, direct current, which can be converted to alternating current.
Fuel cells have a number of advantages over traditional sources of power. Most power plants operate at 35 percent efficiency, and because energy is lost when the electricity is transmitted across a city or region, the net efficiency drops to 31 gyP664 -- .
Fuel cells operate at 40 percent efficiency with no loss of power. Because the cells emit virtually no pollutants and are no louder than an air conditioner , they can be placed directly where the power is needed. A power ''bonus'' is provided by waste heat in the form of hot water and low-grade steam that brings efficiency up to 80 percent.
Commercial development of fuel cells has had a rocky road in the years since they first appeared in the space program. Current problems revolve around technical hitches and a lack of enthusiasm in the marketplace.
Technologically, the problem is finding a way to mass-produce key components. At the same time, potential customers want to see a finished, efficient product before offering a commitment to buy from fuel-cell manufacturers, who, in turn, need that commitment to justify allocating development funds.
''The most absent thing at the moment is market pull,'' says William H. Podolny, fuel-cell-program manager for United Technologies Corporation (UTC).
''Utilities are going to wait for demand growth,'' he adds.
Current testing of fuel cells is being sponsored by the Department of Energy (DOE), the Gas Research Institute, and a number of utilities.
UTC has produced three prototypes and plans to keep one for testing. The other two will go to Northeast Utilities, which will place the fuel cell in the Vernon, Conn., office of Southern New England Telephone, and to Northwest Utilities in Oregon.
Forty-eight or 49 additional cells will be deployed by 1983 under a $40 million to $60 million effort headed by DOE. Forty-five of these will likely go to utilities and the rest to the Department of Defense.
Utilities are a prime market because each of the cells is like a miniature, self-contained power plant. Instead of waiting many years and investing massive amounts of capital on a new power plant that may come on line with too much or too little power, a utility would have the option of a building-block system of fuel cells, adding power in increments.
The Pentagon also is eyeing the fuel cells because the Department of Defense operates more than 150,000 generating machines, running from 5 kw to 150 kw, that run at 10 to 20 percent efficiency. By replacing all its generators with fuel cells, the Defense Department could triple the effective power output.
Another plus is the relatively low temperature at which the fuel cells operate. That feature camouflages the fuel cells from heat sensors, which are used in modern warfare to detect an enemy's position.
But the fuel cell's potential isn't limited to utilities or defense applications. The cells also can operate on a number of fuels, including low-grade alcohol and methane gas. Thus, the fuel cells may be a prime beneficiary of synthetic fuel development. And fuel cells could eventually be hooked up to virtually every sewage-treatment plant in the country because of the methane gas produced at the plants.
The fuel cells that will soon be tested are first-generation cells. The electrolyte (or substance through which the electric current is conducted) in them consists of phosphoric acid. The cells may be ready for commercial use by 1985.
A second generation of fuel cells is being developed concurrently by UTC and General Electric. These cells will have a molten carbonate electrolyte and will probably not be marketed until after 1990.