Fusion research. I. What is the program buying the country

The generalizations that fusion would be safer than fission, involve no dangerous radioactive materials, and rely on a cheap and plentiful fuel are potentially true. But it is pointed out that the type of fusion machine that the U.S. program is developing will deliver only some of these advantages. A gap is developing between what the fusion program appears to promise and what it is most likely to deliver. Fusion power would not be infinitely abundant, because the present reactors rely on a fuel cycle that must have lithium, and lithium is not particularly more abundant than the 238U that would fuel the breeder reactor. Fusion power would not be free of radioactive gases because the lithium would be used to breed tritium--a gas more benign than fission products but one that is hard to contain. The fusion reactor would not be free of waste disposal problems, even though the ''spent fuel'' would be nonradioactive, because the burning of the fuel would produce approximately four times as many neutrons as a fission reactor, and such a neutron flux would make all the structural materials of the reactor intensely radioactive--one estimate of the waste disposal problem is at least 250 tons of material every year from each reactor. Finally, fusion power would not be cheap. The greatest potential advantages of fusion occur with advanced fuel cycles which include deuterium with deuterium; deuterium with helium-3; helium-3 with helium-3; and hydrogen with boron. Fusion with these fuels could be a clean process, but most research is directed toward fusion of deuterium and tritium. The funding of the program in the U.S. has seen the magnetic fusion budget exploding from $38 million in 1973 to $279 million in 1977. A second article will clarify the properties of various types of fusion reactors