Atambir Rao, a nuclear engineer who spent nearly two decades as program manager for General Electric’s next-generation nuclear-reactor design, believes that the countries that are most in need of nuclear power are developing countries like his birthplace, India. Rao says, “Today, the biggest challenge for nuclear is the stranglehold the developed nations have put on it with sanctions.”
The reactor project whose development Rao led was the Economic Simplified Boiling Water Reactor (ESBWR), one of the generation-III nuclear-reactor designs that incorporate the improved fuel technology and passive safety systems–whereby the reactor automatically shuts down safely in any emergency without operator action or electronic feedback–that have been developed over the past quarter century. In 2007, with multitudes in India and China approaching lifestyles comparable to those in the developed nations, and with planetary climate change from carbon-dioxide emissions increasingly manifest, it’s worth stressing that nuclear power remains the sole existing energy technology that’s both proven and zero carbon. The critical question for the technology’s future is whether the forbiddingly high capital costs and lengthy construction times attached to it in the past still apply.
In fact, gen-III reactors like the ESBWR do seem to possess the relative cheapness and ease of construction necessary for nuclear power to potentially establish itself as the primary electrical generation technology for national grids, both in the developed world and in countries like China and India. Per Peterson, UC Berkeley professor of nuclear engineering and part of the team responsible for the ESBWR, says that the design represents a reduction in capital costs of 25 to 40 percent. “In terms of competing with coal-burning plants, that’s significant,” he says. “If you can displace coal with less expensive options, then it becomes a different future.” Peterson adds a couple of qualifiers: “Over the last year, costs have risen for all the energy technologies due to rising commodity costs. So both coal and nuclear cost estimates have been growing. On the other hand, I think we’ve now reached the tipping point on climate-change legislation. If we get carbon controls, there’s no question the equation changes.” In other words, carbon controls would go some way toward building into the use of fossil-fuel-burning power plants the externalities, or hidden costs, currently not included in consumers’ utility bills or paid for by the power companies.
Today, reactor design has more than a half-century of art behind it, so gen-III reactors resemble their 1970s-era generation-II predecessors, much as a Toyota Prius hybrid resembles a vintage 1972 Pontiac, with the progressive trend being toward radical simplification that eliminates the batteries of complex mechanisms built into the earlier designs. The ESBWR replaces previous reactors’ complex systems for residual heat removal with a design that uses no pumps or emergency generators–in fact, it possesses no moving parts at all, except for the neutron-absorbing control rods that are pulled partway out from its core so that nuclear fission can proceed. That fission reaction boils the water in the ESBWR’s core, which becomes steam that gets carried away to large tubes in which it rises, releases its energy to turbines, and then condenses so that gravity causes it to flow back down to the core as water again. In short, the ESBWR runs wholly on natural circulatory forces. Rao says, “It could not be simpler. The control rods get pulled out, water comes in, and steam goes out, carrying heat that gets turned into electricity.”
This simplicity of design also features in other gen-III reactor designs like the Westinghouse AP1000, which has 60 percent fewer valves, 75 percent less piping, 80 percent less control cabling, 35 percent fewer pumps, and 50 percent less seismic building volume than currently operational reactors. This trend becomes more pronounced in gen-IV designs like the pebble bed reactor. In conjunction with “the modern computer-aided manufacturing technologies currently used most extensively in the ship-building industry,” Peterson says, what’s now possible is a modular approach to nuclear-plant construction, whereby large segments of the plants will be prefabricated in factories.
This new context of markedly cheaper, more easily constructed reactors clearly has the potential to invalidate some long-cherished assumptions–and not just those of antinuclear Western environmentalists, whose claims were that nuclear power would always remain dependent on government subsidies. It’s in this context, for instance, that International Atomic Energy Agency (IAEA) deputy-director general Tomihiro Taniguchi recently reported that six Middle Eastern countries–Egypt, Morocco, Algeria, Saudi Arabia, the UAE, and Tunisia–have expressed interest in building nuclear plants. Egypt, in particular, has specific plans for four reactors and has been checking out the options.
Much of the materials and knowledge employed in a civilian nuclear program can be used to develop nuclear weapons. What should an international policy to resist nuclear-weapons proliferation look like in a 21st century in which climate change, depletion of fossil fuels, and radically simpler, cheaper nuclear-reactor designs will be prominent features of the landscape?
The IAEA has proposed a nuclear “fuel bank,” whereby the agency would run a backup supply for nuclear reactors throughout the world on a nondiscriminatory, nonpolitical basis that would thereby reduce the need for countries to develop their own uranium. Simultaneously, the Bush administration is pushing its plan for a Global Nuclear Energy Partnership (GNEP), which would be an international collaboration to reprocess spent nuclear fuel so as to render the plutonium in it usable for nuclear reactors but not for nuclear weapons. Of these proposals, Jeffrey Lewis, of Harvard University’s Belfer Center for Science and International Affairs, comments, “A forward-looking nonproliferation policy would have elements of the Bush administration’s Global Nuclear Energy Partnership, in that it’d have a renewed commitment of the Non-Proliferation Treaty’s inherent bargain–that is, states that refrain from developing nuclear weapons get the benefits of nuclear technology.” But Lewis isn’t optimistic about the Bush plan’s chances. “I don’t think that the Bush administration’s proposals on restricting access to fuel-cycle technologies will be met with much international enthusiasm, because they’re seen as ad hoc, and the Bush administration has so little credibility on proliferation issues. The Bush administration’s deal with India, for instance, suggests that rules aren’t really part of the equation, that what’s more important is a state’s current relationship with the U.S. and its relative power in the international system.”
Lewis approves of the IAEA fuel-bank proposal and of international nonproliferation agreements in general. “In some ways, the current situation with Iran represents a healthy, successful example of what a nonproliferation regime can do, because the red flags are up,” he says. “If, given several years before Iran’s capabilities reach fruition, we can’t come up with a workable solution, it strikes me as a much broader policy failure than can be pinned on the nonproliferation regime. It’s not the nonproliferation regime’s fault if the Bush administration can’t figure a way out of this. In fact, you’ll never create a nonproliferation regime that’s idiot proof: they’ll just build a better idiot.” Lewis concludes, “I’m not so worried by the spread of reactors so much as by the spread of enrichment and reprocessing capabilities. I’m particularly concerned about centrifuge enrichment as a proliferation challenge.”
Peterson echoes this concern. But he also stresses the need for more clarity in discussions of what the threats are: “In talking about nuclear energy and proliferation resistance, we commonly confuse quite different things: state proliferation and terrorist theft of nuclear materials. If we have clarity about each category of threat, it’s much clearer where the largest vulnerabilities are and what our strategy is to counter the risks.”
Peterson sees five threat categories, three related to state proliferation and two to subnational actors.
First, there’s the possibility of clandestine diversion of materials from state facilities operated within the Non-Proliferation Treaty (NPT), which is best prevented, Peterson believes, by more-comprehensive IAEA safeguards on facilities. Second, there’s the possible production of materials in clandestine state facilities, which Iran is currently suspected of. The main preventative tool here, Peterson says, is the export controls system, which monitors exports of dual-use equipment and hopefully sends up red flags. Additionally, major changes in the NPT after the discovery of Iraq’s secret enrichment program in the 1990s now let the IAEA perform inspections anywhere in a country and use information provided by a wide number of sources, including other nations’ intelligence services. Third, there’s the risk that a country could abrogate the NPT–as North Korea did–and overtly misuse facilities and materials; this is best countered by limiting the dispersion of the most sensitive technologies, which are enrichment and reprocessing capabilities, and by effective international action to make it highly unattractive for countries to abrogate the NPT. Fourth, there’s the possibility of terrorist theft of materials for nuclear explosives or for RDDs (Radioactive Dispersal Devices); in this context, Peterson says, attention should be focused both on ensuring that there’s adequate physical protection–particularly for stocks of separated plutonium and highly enriched uranium–and on whether all the links in the chain are secure. For example, Peterson says, “it doesn’t make sense to call for further upgrades for physical security for nuclear materials at U.S. sites when we haven’t yet fixed the security of nuclear materials in the former Soviet Union.” Fifth, there’s the threat of radiological sabotage, which means generating a deliberate release by attacking a nuclear facility. “There, what you want to do is make it so difficult that terrorists give up and go elsewhere,” Peterson says. “With the ESBWR, for instance, you could fly a plane into it and it’ll shut down safely.”
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