Thirty years ago, in March 1979, a group of badly trained operators in the control room at Three Mile Island's unit 2 confronted a minor malfunction. The problem, a simple pump shutdown, was quickly made worse by an instrument panel that failed to inform the operators about a stuck valve and by an alarm system that overloaded after the first malfunction. The operators botched an attempt to solve the rapidly escalating problem, allowing a small leak to drain most of the cooling water out of the $700 million reactor. In about two hours, they converted America's newest nuclear plant, which had begun commercial operation just three months earlier, into a $1 billion liability.
The event at the reactor, near Harrisburg, PA, provoked near-panic, and although government reports said the maximum possible radiation exposure was too small to have much effect on human health, one major casualty was the outlook for the nuclear industry itself. The meltdown did not end the first round of nuclear construction in this country; 50 reactors already under construction were completed after the accident, and orders for new plants had effectively ceased anyway. (The last order for a nuclear plant that was actually built came in 1973.) But for years to come, it remained unthinkable to plan new reactors as part of the nation's energy portfolio.
Given pressures to reduce carbon dioxide emissions from fossil-fuel power plants, however, construction of nuclear plants could be poised to begin anew. The technology has grown more reliable and more efficient. Reactors now run 90 percent of the hours in a year, compared with less than 60 percent in 1979, effectively cutting the capital cost of a kilowatt-hour by about a third. Meanwhile, other sources of power have started looking a lot worse. Congress seems likely to put some kind of price tag on carbon dioxide emissions, so the price of coal-produced electricity could rise by 30 to 50 percent. The price of natural gas is low right now but has been more volatile than the price of oil in the past few months as surging supplies and lackluster demand play leapfrog. Such volatility makes electric companies reluctant to rely heavily on gas.
All the same, the nuclear industry faces tremendous risks, though their nature has changed since 1979. As the possibility of an accident that panics or injures the neighbors has diminished, the likelihood has grown that even a properly functioning new reactor will be unable to pay for itself. And changes in the utility industry since 1979 mean that this time, the money a company wastes may be its own.
Gopal R. Rao, Ph.D.
Web Science Editor
Materials Research Society (MRS)