The amorphous solar cell: A better way to plug into the sun?
If electricity, which adds so much comfort and convenience to your life, soon comes inexpensively from the roof of your house, you can probably thank one man. He is Stanford R. Ovschinsky, who, in the face of a worldwide ''it can't be done'' mentality, began developing a totally different type of photovoltaic (electricity from the sun) cell back in 1960.
Now, almost a quarter of a century later, Mr. Ovschinsky and his principal backer, the Standard Oil Company of Ohio, say that the dream of cheap power from the sun is about to be realized on a broad scale.
Similar promises have been made before, and one by one they have failed to materialize. But this time it will be different, Ovschinsky believes, because a system for mass production of the new cells has been developed and tested in Japan. Ovschinsky's company, Energy Conversion Devices Inc. of Troy, Mich., found in Japan, as he puts it, the investors ''who were prepared to take the critical risk.''
All that remains to make this type of solar energy competitive with oil or nuclear generation is the establishment of larger fabricating facilities. With Standard Oil's backing, that, too, is apparently about to happen.
Construction on two United States facilities, one in Michigan, another in Ohio, is to begin soon; both are projected to become operational by the end of 1984.
At a time when dollar-a-gallon gasoline seemed more remote than the 21st century to most people, Ovschinsky foresaw the fuel crunch that, in his view, was inevitable. He decided to do something about it.
Specifically, he sought to develop a technology that would eliminate the need to use fuel oil in electric-power generation. To do this he would have to make solar electricity competitive with the conventionally generated commodity. That, in turn, meant developing a totally new type of solar cell that could be produced at a fraction of the cost of the silicon-crystal cells that were the heart of the photovoltaic industry.
Indications are that he has done just this. The Japanese facility has been producing his new amorphous, or noncrystalline, cells 20 hours a day throughout much of 1983.
Power from the sun that is nonpolluting and as cheap as the conventionally generated product could be as close as 1987 or '88, according to the company's analysis.
In 1960, Ovschinsky believed that if an amorphous cell could be developed, it would be the key to much cheaper electricity from the sun. Single-crystal silicon has to be ''grown'' slowly, a process that consumes considerable energy and is limited to a maximum size of about 6 inches in diameter. Afterward the crystal is cut into thin wafers that form the individual solar cells. In contrast, the amorphous, or randomly mixed, silicon can be rapidly formed into an ultrathin continuous film, using very little energy. As a result, amorphous cells are far less costly to produce. They can also be turned out in much larger sizes and shapes than is possible by the old method.
At the time, Ovschinsky and his colleagues were pretty much alone. As Dr. David Adler, professor of electrical engineering at the Massachusetts Institute of Technology, sees it, they were ''the true pioneers.'' Even nine years later, at a gathering of scientists from around the world in Cambridge, England, a paper was delivered that ''proved'' the impossibility of amorphous solar cells.
Now Professor Adler believes the Ovschinsky team has effectively achieved ''the impossible.'' From their point of view, the research and development phase is over, the technology is an accomplished fact, and only the manufacturing capacity needs to be enlarged to further bring down costs.
To the skeptics, and there are still many, Dr. Adler, who has done some consulting work for Ovschinsky, says: ''The machine is there in Japan, for anyone to go and see. It works - 20 hours a day, in fact - turning out a consistently good product.'' Overly optimistic promises about solar energy failed to materialize because they were based on untested theory, says Dr. Adler. There is nothing, in his view, that is ''untested'' about the Ovschinsky cells. As he sees it, only the economies of scale are now needed to make photovoltaics totally competitive with utility-generated power.
Standard Oil of Ohio (Sohio), also convinced of the breakthrough, has joined Energy Conversion Devices Inc. to form Sovonics Solar Systems specifically to manufacture the new amorphous cells here in the US.
The new process, then, holds out the promise that photovoltaics could compete on a cost-per-kilowatt-hour basis in the open market. That could come in as little as three years with solar tax breaks, and in five years without tax breaks if the projected increase in capacity at the US facilities takes place.
Three years ago, Sovonics, in partnership with the Sharp Corporation, erected a facility in Shinjo, Japan, to manufacture the new solar cells. It required the development of special machinery to manufacture the solar cell material (a light-sensitive film on thin sheet metal backing) through a continuous-web process. In this process the new product is turned out in a similar manner to photographic film, and the ultimate product is cut to whatever size is needed.
Full-scale commercial production has been under way since early 1983. With the manufacturing process now established, the scale-up to wider rolls and more rapid production is considered straightforward. This higher production rate is seen as the key to dramatic price reduction, from its present less-than-$5 a peak watt down to around $1 a peak watt, which translates to approximately 6 cents a kilowatt hour. This would make it competitive with conventionally generated electricity. Current crystal-cell photovoltaic costs range from a low of $6 a peak watt to several times that figure.
Initial production in the US will meet the needs of consumer items (calculators, radios, and the like) and industrial products (such as battery chargers, remote outdoor lighting, and irrigation pumps).
In three or four years, however, those amorphous cells could be sitting on your south-facing roof bringing TV pictures into your living room, cooking your dinner in the kitchen, and maybe heating your bath water - all at no more cost than if you had a power line strung in from the street.