Will lasers brighten nuclear's future?
New process could replace centrifuges but renew threat of nuclear proliferation.
Inside a bland industrial building in Wilmington, N.C., an experiment is in the works that could vastly reduce the cost, time, and space needed to make fuel for nuclear power plants and, some nonproliferation experts say, for nuclear bombs as well.
In that building, secret uranium-enrichment technology licensed by GE-Hitachi Nuclear Energy is nearing a pilot test. If successful, the new technology will enable the company to supply low-cost nuclear fuel to power reactors worldwide, officials say.
Only broad outlines of the “Separation of Isotopes by Laser EXcitation,” or SILEX technology, are public. Most details are classified under the Atomic Energy Act.
But it would not take much – just a signal from Wilmington of SILEX’s success in the months ahead – to unleash a global push by companies and nations to develop similar laser-based technology, nonproliferation experts, scientists, and US government studies warn.
“The threat is there,” says Edwin Lyman, a nuclear nonproliferation expert with the Union of Concerned Scientists, a research and advocacy group in Cambridge, Mass. “If [GE-Hitachi] succeeds in overcoming remaining technological hurdles, the resulting laser-enrichment would be extremely vulnerable to proliferation. It’s also a technology that several countries would likely pursue.”
Henry Sokolski, director of the Nonproliferation Policy Education Center in Washington, is worried about SILEX too. “If it works, it has enormous industrial implications with the US perhaps bringing back all the enrichment services it has lost to Europe and Russia,” he says.
“But how long can you keep this process secret and out of the hands of proliferators? That’s the real question.”
The US Department of Energy, which oversees nuclear power, is not worried.
“Any program to build additional enrichment facilities in the United States will be evaluated for its safety, environmental, and nonproliferation characteristics before it is licensed to operate,” the DOE said in a statement responding to Monitor queries.
Still, SILEX’s success is hardly guaranteed. Laser isotope separation, or “laser enrichment,” is not new. It has a reputation as a fiendishly difficult technology that has defied researchers for decades. Most of the 18 countries that once pursued it have given up.
Jeffrey Eerkens, a laser expert in northern California, is one of the few researchers familiar with many aspects of the SILEX technology. One of the key hurdles has always involved the infrared laser, he says.
“For 20 years, everyone has been trying to find a good 16-micron laser to do uranium enrichment,” he says. “We know how to do the harvesting [of enriched uranium], now it’s the laser.”
Beyond a few trade reports, little attention has been paid to SILEX development, and there seems scant awareness of it in Congress. The US Department of Energy appears bullish on SILEX’s potential to lower the amount of uranium fuel US nuclear power reactors purchase from overseas firms. “Any increase in domestic enrichment capacity will increase US energy self-reliance,” the DOE said in its statement.
While the State Department was unable to provide an official to speak about SILEX, the Nuclear Regulatory Commission (NRC) is familiar with the technology, having approved the first-step SILEX “test loop” this spring.
SIDEBAR: How SILEX works
If all goes according to plan, sometime in the next few months a powerful infrared laser will fire into a chamber containing uranium hexafloride gas, according to a description of the laser-isotope-separation (LIS) process in a 2001 analysis by a researcher at Los Alamos National Laboratory. The beam will excite U-235, the uranium isotope used to make nuclear fission reactions, and enable them to be separated out.
As the gas is cycled through the beam, the process steadily boosts the concentration of U-235. In the end, what precipitates out is a substance with 3 percent or higher U-235 concentration, enough to qualify as fuel for commercial nuclear power plants.
But with minor modifications, such a system could produce the highly enriched uranium used in nuclear weapons. Because of its relatively low power use and compact space requirements, the technology is a threat, says nonproliferation experts.
The NRC’s primary role is to make sure the process “meets all the health and safety requirements,” says Timothy Johnson, a senior project manager at the NRC’s enrichment and conversion branch. He doesn’t know if SILEX technology has yet been reviewed to assess its “proliferation resistance.”
GE-Hitachi, through its public relations firm, declined to make a spokesman available for this article. But officials have in the past been optimistic about the technology licensed in 2006 from Silex Systems, Ltd., the Australian company that originally developed it.
“GE’s agreement with Silex comes at an ideal time, just as the global nuclear industry is preparing to build new reactors around the world,” Andy White, then president and CEO of GE Energy’s nuclear business, said in a 2006 statement after the rights to the technology were acquired. “We expect the SILEX technology to help us fulfill the industry’s growing fuel demands.”
But all enrichment systems can be altered to produce bomb-grade uranium, something that has worried every US president since the 1960s.
Currently, the dominant method to enrich uranium involves centrifuge technology. Iran’s development of centrifuge enrichment has drawn condemnations from the International Atomic Energy Agency, the US, and European nations.
If SILEX is successful, GE-Hitachi could produce low-enriched uranium fuel for power plants at half the cost of centrifuge-based technology, Dr. Eerkens says.
While a boon to the struggling US nuclear fuel enrichment industry, a SILEX success would press other nations to seek laser enrichment, often called LIS, to stay competitive, nonproliferation experts say.
“Once you’ve solved the problem, everyone knows it can be done,” says Charles D. Ferguson, a senior fellow at the Council on Foreign Relations, who has studied SILEX. “France and Russia will pay particular attention because they are competing with the US in fuel services.”
But industry experts dismiss the idea that other countries will ramp up research if the “test loop” sees success.
“Just because it’s been done doesn’t mean another country can do it if they have a few extra dollars,” says Julian Steyn, president of Energy Resources International, Washington-based nuclear-fuel consultants. “I don’t think it’s a major proliferation-prone technology in the right hands.”
“Once LIS is known to work on the pilot-plant scale, research and development can be expected to intensify in several technically advanced countries,” a 1977 report on nuclear proliferation by the US Office of Technology Assessment found. “Some of these countries would probably develop LIS 5 to 10 years after a US demonstration.”
SILEX’s development has been long and tortuous. From the 1970s to the 1990s, the US spent about $2 billion trying but failing to develop an LIS system, Mr. Ferguson says. In 1999, however, President Clinton signed an agreement with the Australian government to bring SILEX technology developed there to the US. In 2001, the US Department of Energy declared certain SILEX information to be “restricted data.”
Then, in October 2006, GE Energy’s nuclear business announced it had reached a deal with Silex Systems to develop the technology.
“Government authorizations” were obtained when GE-Hitachi licensed the technology in 2006, the company said. This week it reiterated that SILEX, which it has dubbed Global Laser Enrichment, has federal clearance and oversight.
“Global Laser Enrichment (GLE) has obtained the required security clearance from the NRC, which dictates a security program to safeguard information,” the company said in an e-mailed statement.
As SILEX moves into its testing phase, the Nuclear Regulatory Commission is confident its procedures will keep vital data safe. Marvin Miller is less certain of that. A retired MIT researcher, he prepared classified government studies in the 1980s about the proliferation threat posed by the same type of laser-enrichment process now coming to fruition as SILEX.
“Laser isotope separation has not been a proliferation threat because it hasn’t worked before,” he says. “Now, if you can get SILEX to work, it would indeed be a proliferation concern.”
Eerkens, who has pursued similar laser-enrichment technology, is concerned about SILEX or other laser technology as a proliferation threat.
It would, he says, obviously be “easier to hide 20 or 30 lasers than 10,000 centrifuges.” One thing he is certain about: In coming months, every scrap of information about SILEX will get plenty of scrutiny from outside US borders. If GE-Hitachi moves ahead with a commercial-scale SILEX plant as the company says it wants to do next year, it will be a sure sign the test was a success.
“The Russians, the French, the enrichment companies – they’re all watching to see if SILEX is working,” Eerkens says.