On the outskirts of this sprawling city lies a unique experimental power plant that could buy the industralized world another 10 years in learning how to deal with the growing shortage of oil and natural gas.

The plant is the only one on earth making use of a phenomenon called magnetohydrodynamics (MHD) to extract more electricity out of the heat generated by burning fuels such as natural gas. Still experimental, the Soviet plant has been producing electricity when it has been runnin for the last two years.

"We have not kept a record of how many kilowatts hours we have produced," Dr. Yevgeny Shelkov, deputy director of the Soviet Academy of Sciences' Institute of High Temperature, told touring American journalists the other day, "but we have successfully run this plan for several thousands generating as much as 20,000 kilowatts."

Looking like a giant expresso machine, the plant is now idle, many of its shiny steel and red-painted parts stripped for repairs and changes. It will start up again just after Thanksgiving using a piece of machinery developed and provided by the U.S. Department of Energy to help prove the concept of magnetohydrodynamics.

The American machine is the largest superconducting magnet ever made, a cyclindrical piece of hardware so fragile and so heavy (40 tons) that it was flown here in a giant Lockheed C5 aircraft from Chicago's Argonne National Laboratory where it was built last year.

The U.S. magnet is one of two that form the heart of this experimental plant. The other magnet is of Soviet manufacture and is made of pure iron weighing 2,000 tons. It dwarfs its American counterpart.

The U.S.

The joint project is part of U.S.-Soviet cooperation in the field of energy and is viewed by American officials as one of the more successful among 11 bilateral cooperative arrangements concluded four years ago. By providing one component to the already existing Soviet facility, the United States shares fully in thre results of the experiment. American experts have full access to the Soviet facility.

The magnet, which is on loan to the Soviets, has been constructed in a way that it is virtually impossible for the Russians to disassemble it, or copy its precise design, according to sources familiar with the project.

By shipping the magnet to Moscow, the United States is said to have saved an estimated $40 million which would have been required to duplicate the Soviet facility.

Magnetohydrodynamics is a concept that has long been known but never put into use until the Soviets started a tiny pilot plant six years ago alongside the Moscow River. Near the Kremlin, this plant generates 2,000 kilowatts of electricity used in part to light up the Kremlin walls at night.

The smaller plant goes under the ironic name of U-2, recalling the American spy plane that figured so prominently in one of the low points of U.S.-Soviet relations. The larger plant is called U-25 (U is the first letter in the Russian word for facility), meaning it has the potential for generating 25,000 kilowatts.

So far, U-25 has produced a little more than 20,000 kilowatts each of the dozen or so times it has been run. That may not sound like much but it is new, so complex and so close to the edge of technology. It is also enough to light up a small town.

Electric power plants are notoriously inefficient, burning, oil, gas and coal in prodigious quantities around the world. Fully 70 percent of the heat is generated by these burning fuels is lost in the boilers where steam is made, in the turbines where it is utilized and out to the stack when it is discharged.

Magnetohydrodynamics promises to cut that loss in half and extend the life of oil, gas and coal supplies by an equal amount.

There is nothing easy about starting up such a plant, as the engineers here at the Institute of High Temperature know quite well.

First, natural gas is burned in huge heaters that are force-fed a pressurized mix of air and puere oxygen to drive temperature up as high as 5,000 degrees Fahrenheit. This is the point at which some of the gas molecules become electrically charged. At that point, sees of cesium metal are pumped into the mix to give them even more of an electrical charge.

The mix is then driven through a ceramic "channel" enclosed by a magnetic field. There are two such channels in the Soviet device, one covered by the 2,000-ton Soviet iron magnet and the other by the 40-ton superconducting U.S. magnet.

The walls of the channel serve as electrodes to energize the superheated gas. The magnets serve to brake this rapidly flowing gas in such a way that most of the heat in the gas is converted at once to an electric current. An efficiency level of 60 percent is achieved in generators that never before did better than 30 percent.

The Soviets are proud that they are the world leaders in the field. They plan to construct additional facilities that would produce as much as 500,000 kilowatts by 1985. They see the day when their countrside will be dotted with as many as 20 such plants.

"By the year 2,000," says Academician Alexander Sheyndlon, director of the Institute of High Temperature, "I believe we will be producing 2 million kilowatts of power with MHD."

The United States is more than a silent partner in all this. The Energy Department next year will ship the Soviets an experimental channel to handle the enormous heats encountered in the experiments. The magnet that is here now is expected even by the Soviets to be the forerunner of whatever giant superconducting magnets are built to run the first commercial plants.

"Superconducting magnets are the future," admits Yevgeni Shelkov. "They are smaller, they use less power and their efficiency is higher. There can be no doubt about that."