Environmental Problems, Their Causes, and Sustainability 1

manently in 1998. Because of this experience, othercountries have abandoned their plans to build full-sizecommercial breeder reactors.Is Nuclear Fusion a Feasible Alternative?A Costly 50-Year Dream Still at the LaboratoryStageNuclear fusion has a number of advantages, butafter more than five decades of research and billionsof dollars in government research and developmentsubsidies, this technology is still at the laboratorystage.For decades, scientists have hoped that controlled nuclearfusion will provide an almost limitless source ofhigh-temperature heat and electricity to supply mostof the world’s commercial energy. Research has focusedon the D–T nuclear fusion reaction, in whichtwo isotopes of hydrogen—deuterium (D) and tritium(T)—fuse at about 100 million °C (180 million °F; Figure3-16, p. 50).According to a 2001 Department of Energy taskforce, fusion energy has a number of important advantages.They include no emissions of conventional airpollutants or carbon dioxide, an almost infinite fuelsupply (water), and wastes that are much less radioactiveso they would need to be stored for only about100 years.There would be no risk of meltdown or release oflarge amounts of radioactive materials from a terroristattack and little risk from additional proliferation ofnuclear weapons because bomb-grade materials (suchas enriched uranium-235 and plutonium-239) are notrequired for fusion energy.Fusion power might also be used to destroy toxicwastes, supply electricity for ordinary use, and decomposewater and produce the hydrogen gas needed torun a hydrogen economy by the end of this century.This sounds great. So what is holding up fusionenergy? After more than 50 years of research andexpenditures of more than $25 billion of mostly governmentfunds in the United States, controlled nuclearfusion is still in the laboratory stage. None of the approachestested so far have produced more energythan they use.If researchers can eventually get more energy outof nuclear fusion than they put in, the next step wouldbe to build a small fusion reactor and then scale it upto commercial size. This is an extremely difficult engineeringproblem. Also, the estimated cost of buildingand operating a commercial fusion reactor (even withhuge government subsidies) is several times that of acomparable conventional fission reactor.Proponents contend that with greatly increasedfederal funding, a commercial nuclear fusion powerplant might be built by 2030 or perhaps by 2020 withemphasis on developing a new technique calledmuon-catalyzed fusion. However, many experts donot expect nuclear fusion to be a significant energysource until 2100, if then.What Should Be the Future of NuclearPower in the United States? Phase Outor Keep Options OpenThere is disagreement over whether the UnitedStates should phase out nuclear power or keepthis option open in case other alternatives do notpan out.Since 1948, nuclear energy (fission and fusion) has receivedabout 58% of all federal energy research anddevelopment funds in the United States—compared to22% for fossil fuels, 11% for renewable energy, and 8%for energy efficiency and conservation. Because theresults of such a huge investment of taxpayer dollarsin nuclear power have been disappointing, some analystscall for phasing out all or most government subsidesand tax breaks for nuclear power and using themoney to subsidize and accelerate the development ofother, more promising energy technologies.To these analysts, nuclear power is a complex, expensive,inflexible, and centralized way to produceelectricity that is too vulnerable to terrorist attack.They believe it is a technology whose time has passedin a world where electricity will increasingly be providedby small, decentralized, easily expandablepower plants such as natural gas turbines, farmsof wind turbines on land and at sea, arrays of solarcells, and hydrogen-powered fuel cells. Accordingto investors and World Bank economic analysts, conventionalnuclear power simply cannot compete intoday’s increasingly open, decentralized, and unregulatedenergy market unless it is artificially shieldedfrom free-market competition by huge governmentsubsidies.Proponents of nuclear power argue that governmentsshould continue funding research and developmentand pilot plant testing of smaller and potentiallysafer and cheaper reactor designs along with breederfission and nuclear fusion. They say we need to keepnuclear options available for use in the future if variousrenewable energy options fail to keep up withelectricity demands and reduce CO 2 emissions to acceptablelevels. Germany does not buy these argumentsand has plans to phase out nuclear power overthe next two decades.xHOW WOULD YOU VOTE? Should nuclear power be phasedout in the country where you live over the next 20 to 30 years?Cast your vote online at http://biology.brookscole.com/miller14.http://biology.brookscole.com/miller14377