Feb 25 - McClatchy-Tribune Regional News - Mike Freeman The San Diego Union-Tribune



A San Diego defense contractor has come up with an early design for a compact commercial nuclear reactor that aims to generate power using the nation's stockpile of spent nuclear fuel and other nuclear waste.

General Atomics' Energy Multiplier Module, or EM2, is among a handful of relatively miniature reactors that are being developed by companies seeking to capitalize on a renewed interest in nuclear power.

EM2, though, has zeroed in on a key problem with nuclear power: what to do with the waste. By developing ways to tap into energy remaining in spent fuel from large reactors or depleted uranium, the so-called fast reactor could help ease the thorny problem of finding a home for radioactive waste.

EM2 has a long road ahead and easily could be derailed by anything from shifting political winds to a lack of development funding.

 "We're trying to get the U.S. Department of Energy, for example, to move forward with supporting this," said John Parmentola, senior vice president for energy at the privately held General Atomics. "And we're also looking toward the private sector economics to see what the opportunities are, to see if there is a new path for the U.S. to carve out in nuclear energy."

The design calls for a reactor about 60 feet long and 16 feet in diameter -- small enough to be transported on a flatbed truck -- that can be used as an on-site power source by manufacturers, for example.

General Atomics expects it will take 12 years and $1.7 billion to perfect the design, get regulatory approvals and build its first functioning EM2 reactor.

"If you ask me what stage we are in, we're in the early stages," Parmentola said. "We've looked at all the major issues associated with the design, and it's enough to tell us that this is a concept that is worth pursuing."

The nuclear industry has been stagnant since the late 1970s, with only a few new reactors built in the United States, mostly for export. This month, President Barack Obama promised $8 billion in loan guarantees in the 2011 federal budget for two nuclear power plants in Georgia.

The administration also pledged to triple existing loan guarantees for nuclear power construction to $54.5 billion. It believes the loan guarantees can help awaken the industry, creating jobs and generating electricity without burning fossil fuels that produce greenhouse gases.

Opponents were quick to blast the loan guarantees as a taxpayer boondoggle that will produce more radioactive waste without a place to put it.

That's a problem EM2 hopes to help solve.

Fast-reactor technology been around for years. But it was shelved in the 1970s in the United States in favor of steady, thermal reactors because of fears over nuclear proliferation, said Bill Reckley, branch chief for advanced research programs at the U.S. Nuclear Regulatory Commission.

Thermal reactors don't come close to using all the energy potential in their fuel rods. Getting at that leftover energy required reprocessing, which produced relatively rich fissile material, raising fears that dangerous nuclear material would become too widely available.

With EM2's design, spent fuel can be tapped without reprocessing, according to General Atomics. The company proposes kick-starting the used rods by using what Parmentola called low-enriched uranium.

Reckley noted that there are proliferation concerns surrounding enriched uranium as well, but "if they forgo the reprocessing step, that may alleviate the proliferation risk," he said.

Other companies also are proposing compact reactor designs, including General Electric's Prism reactor and proposed TerraPower reactor project. Toshiba also has one in the works.

"Is it bizarre? Not really, because there are a number of similar proposals being talked about right now," Reckley said.

What makes EM2 different, though, is its attempt to use nuclear waste as a fuel source. General Atomics estimates that used and depleted nuclear fuel in the United States contains energy equivalent to 9 trillion barrels of oil -- more than three times the known oil reserves in the world.

"Spent fuel rods still contain more than 95 percent of their energy," Parmentola said. "That tells you it is a valuable resource."

General Atomics is perhaps best known for the work of an affiliate: General Atomics Aeronautical Systems, maker of the Predator and Reaper drone aircraft widely used in Iraq and Afghanistan.

The company has a long history in energy, including operating an experimental fusion facility in San Diego -- aimed at creating energy by joining atoms, rather than splitting them -- in conjunction with the Department of Energy. It also has a nuclear material transport and storage business.

Since October, the EM2 design has been under peer review by a panel convened by the Department of Energy. The company is waiting to hear what the experts think of its design and its potential.

Much of the design and research for EM2 will be in San Diego, Parmentola said. Work involving nuclear fuel likely would be performed at a national nuclear laboratory elsewhere, he said.

Daniel Kammen, a professor in the energy resources group at the University of California Berkeley, said the EM2's basic technology is well-known.

"So this is something that from a technology perspective looks pretty good," Kammen said. "Does that mean it's guaranteed to work? No. But there aren't any show stoppers."

EM2 would run hot, at 1,562 degrees Fahrenheit (850 degrees Celsius), and would be capable of producing about 240 megawatts of electricity. Because of its size and heat production, General Atomics believes it would be best used in processes that require a lot of heat, such as fertilizer production or chemical processing. It would be cooled by helium gas, not water like larger reactors, and thus wouldn't need to be located near a water source.

Unlike large, 1,000-megawatt nuclear plants common today, for which the reactor is built largely on site, EM2 would be manufactured in a factory and hauled to its location. That would help push down the cost per kilowatt hour to 30 percent below current standard large reactors.

Kammen said manufacturing in the United States is important to re-establishing a nuclear power industry.

"If you want to rebuild the nuclear industry and capture a lot of the job benefits, you want to build the hardware here at home, not just license it from overseas," he said. "And the attractiveness is we can scale up production much faster by doing these small, modular ones than by doing the large ones."

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