American Scientist

Megawatts and Megatons: A Turning Point in the Nuclear Age? Richard L. Garwin and Georges Charpak. xvi + 412 pp. Alfred A. Knopf, 2001. $30.

Megawatts and Megatons is two books: one a good primer on nuclear power and the other a detailed discussion of nuclear weapons and potential paths for reduction in total numbers of such weapons. Authors Richard L. Garwin and Georges Charpak are well-known scientists who have been involved in significant developments in theoretical and experimental physics; both are National Academy members, and Charpak won the Nobel Prize in Physics in 1992. Reading the early chapters is like listening to two friends sitting around talking about what is an atom, what is energy and related issues. The writing is quite relaxed.

The authors warn the reader in the introduction that "this is neither a physics nor an engineering text. But, like any serious book on nuclear energy, it contains both physics and engineering." Some material may not be easy for the lay reader, such as the discussion of the linear, no-threshold approach to low levels of radiation exposure, which could be quite difficult for someone with no background on this important and still hotly debated issue.

The book is quite comprehensive in its treatment of nuclear reactors and provides a good background on the development of the nuclear power programs in the United States and France. Charpak's knowledge of the French program is useful in providing insights into what is viewed as one of the most successful national nuclear power programs. Although they are basically favorably inclined toward nuclear power, the authors acknowledge its problems, including discussion of accidents such as those at Three Mile Island, Chernobyl and Tokai-mura, and the resulting fatalities in the Soviet Union and Japan. They see the lack of an acceptable permanent solution for disposing of the high-level waste produced by plants as a major obstacle to continued growth of nuclear power.

The book does provide a useful introduction to nuclear reactors and nuclear engineering issues. The role of nuclear power in addressing energy problems, including global warming, is treated objectively in my view, but I suspect that some environmentalists would see the presentation as pronuclear. The authors estimate the number of annual deaths in the first 500 years from the operation of a 1-gigawatt electric nuclear power plant and a 1-gigawatt electric coal plant and find that the coal plant would be responsible for 5 to 10 times as many deaths; but if the estimates are extended to 10,000 years, regular nuclear power and coal are equal, and reprocessing spent nuclear fuel leads to twice as many deaths as a result of carbon-14 release.

The authors are not advocates of the breeder reactor, that long-desired goal for many nuclear power advocates. They correctly note that current breeder designs are more expensive than light-water reactors and that the breeder would not be needed until the price of uranium rises substantially. They recommend that additional effort be made to develop means of extracting uranium from seawater, which would provide hundreds of years of supply before breeders would become necessary.

The discussion of nuclear power and associated issues is valuable, but what makes the book unique is that Garwin and Charpak are also experts on nuclear weapons and nonproliferation. Many authors with nuclear reactor expertise really know very little about nuclear weapons, and often their prescriptions for proliferation control evidence that fact. On the other side, many who write on nonproliferation issues come from the political science world and have little understanding of nuclear fission or nuclear reactors; often their proposals to clamp down on nuclear power demonstrate that lack of understanding.

An extensive discussion of the issues relating to nuclear weapons notes that, as several reports from the National Academy of Sciences have stressed, quite usable nuclear weapons can be made from the plutonium separated from spent nuclear fuel. For this reason, separated plutonium must be safeguarded. The authors also write that reprocessing, which produces the separated plutonium, is not economical. There is a good discussion of the means to eliminate or make less available the weapons-grade plutonium coming from the significant reduction in nuclear weapons by Russia and the United States as a result of the Strategic Arms Reduction Treaties (START). This is particularly timely now, because the Bush administration has renewed its commitment to fund programs by which the United States assists Russia in guarding and disposing of its weapons materials. However, the administration also has said that it will be looking for lower-cost, faster ways to address plutonium disposition. This book could be very useful in educating those who might think plutonium disposition is a simple problem. It is not.

Some nuclear power experts, particularly those who have spent years examining the details of reactors and reactor accidents, may have quibbles about some of the details in Megawatts and Megatons. If so, these would be only minor flaws in an excellent introduction to very complex issues that have increased in importance as greenhouse warming has become obvious and terrorist threats have become significant.—John F. Ahearne