The Great Breeder Dispute

By current projections, the nation's demand for electricity will double in the decade ahead and multiply as much as six times by the year 2000. Yet the fossil fuels that are needed to generate this crucial power by conventional means--oil, coal, natural gas--are being exhausted at an alarming rate. So, too, are reserves of uranium 235, which nuclear reactors now use as fuel. Meanwhile, such alternatives as harnessing the energy of the sun--or of the earth's tides, winds, or internal heat--remain little more than scientific pipedreams. Even the vision of controlling the power of the hydrogen bomb will probably not be realized, despite recent progress in the laboratory with thermonuclear fusion, before the turn of the century. How, then, can the U.S. meet its impending energy crisis?

National Goal. To many scientists, the answer is all too obvious: the development of a remarkable new generation of atomic power plants called breeder reactors. Named after their capacity to produce or "breed" more fuel than they consume, breeders have already been built and operated experimentally; they could, if technical flaws are overcome, help meet U.S. energy needs by the mid-1980s. But other scientists believe that breeders are a direct threat to the environment and to human life. Thus, when President Nixon recently declared that the construction of breeders was an important national goal and authorized work on a second demonstration plant, he added fuel to a growing, though as yet largely unpublicized scientific controversy.

Like ordinary nuclear reactors, breeders produce heat through fission--the familiar process of splitting unstable radioactive atoms by bombarding them with small, fast-moving particles called neutrons. As the atoms disintegrate, they release large amounts of heat that can be converted into steam and used to drive conventional turbogenerators. They also release additional neutrons, which in turn smash neighboring atoms and thus continue the heat-producing chain reaction inside the reactor.

Ordinary reactors "burn" uranium 235, which eventually becomes stable lead. Breeders use either U-235 or man-made plutonium for fuel, but also use as a "fertile" material (a nonfissionable substance that absorbs excess neutrons freed in the chain reaction and becomes fissionable) another form of uranium called U-238. In addition to being more common than U-235, this uranium isotope, when struck by a hurtling neutron, does not break apart as does U-235. Instead, it absorbs the particle and is transmuted, by 20th century alchemy, into fissionable plutonium. Thus the breeder's fertile material is gradually converted to plutonium, which can eventually be used to refuel the parent breeder and other reactors.

For all their promise, many design problems must be solved before breeders can produce electricity on a commercial scale. One difficulty lies in handling the coolant--the liquid or gas used to transfer heat from inside the reactor's core to a steam-producing boiler outside. Unlike conventional reactors, which use water as a coolant, the so-called liquid-metal "fast breeders" planned by the AEC will use liquid sodium, which is an extremely efficient thermal conductor. But since sodium also burns in air and reacts strongly with water, it requires elaborate safeguards to prevent a mishap that could leak radioactive materials.

Sodium Flow. In addition, engineers have yet to solve the problem of precisely spacing the thousands of stainless steel rods holding the fissionable material in the reactor's core. Unless the sodium can freely flow around the rods, dangerous overheating and melting can result, as demonstrated by a failure of the small experimental Enrico Fermi breeder near Detroit. Nevertheless, the head of the AEC's reactor development program, Milton Shaw, is confident that such engineering problems can be solved as larger reactors are built. "We know how," says Shaw. "It's only a matter of increasing the scale."

Yet many scientists, including H-Bomb Pioneer Edward Teller, continue to have grave reservations about rushing into a breeder program despite the AEC's assurances about the safety of breeders; there will be some 2,500 lbs. of plutonium inside the core of the typical commercial-sized reactor envisioned for the 1980s, enough to make hundreds of Hiroshima-sized atomic bombs. If an accident scattered only a small portion of this highly lethal and durable substance (half-life: 24,000 years) around the surrounding area, it would pose a grave threat. Some breeder critics even claim that if the cooling system broke down, the temperature might rise high enough to produce a nuclear blast. But most scientists are convinced that the configuration of the radioactive fuel and the precise timing necessary to produce an atomic explosion could never be duplicated in a breeder.

Irrational Policy. Through court action, a group called the Scientists' Institute for Public Information is trying to compel the AEC to provide more information about the potential dangers of breeders. The real purpose of the litigation, however, is to force an open debate over the $20 billion breeder program and possibly to scuttle it. Says Environmentalist Barry Commoner, the group's chairman: "Just because the Establishment has had no rational power policy, there's no reason the public should allow itself to be panicked into an irrational policy."

But the AEC and its supporters argue just as passionately for the breeder. They contend that breeders will be more efficient than existing nuclear plants, and will exact even less of an environmental toll. Thermal pollution caused by breeders should be no worse than that from fossil-fuel plants, and breeders will not pollute the atmosphere with soot, carbon monoxide and other products of combustion--though the AEC admittedly still has not found a completely satisfactory way to dispose of radioactive wastes. In addition, the reactor core should be so well insulated by the reactor's three separate heat circulation systems that the escape of any radioactive debris will be extremely unlikely. The AEC, in fact, has moved relatively slowly; the Soviet Union, Britain, France, West Germany, Italy and Japan all have started breeder demonstration projects ahead of the U.S. California's Representative Craig Hosmer, the ranking House Republican on the Joint Atomic Energy Committee, may well have put the debate over breeders into practical perspective. "If we don't build them," he said, "then we'll end up buying them from other countries."

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