Archive for December, 2013

NuScale OnTruck ChenectedAichieOrg

Alternative nuclear rolled ahead a bit this week, as the U.S. DOE agreed to fund NuScale’s small modular reactor, transportable on the back of a truck.

The U.S. Department of Energy has taken another “small” step toward shaking the nuclear industry out of its uninventive ways and towards innovative reactors that augur lower costs and improved operations and safety for a low CO2 future: It has granted up to $226 million in funding to an Oregon startup that is developing a “small modular reactor.”

The award to Corvallis, Oregon-based NuScale Power marks the second tranche of a $452 million program that DOE announced in March 2012. It comes a year after DOE’s first grant to North Carolina-based Babcock & Wilcox. That grant was reported at up to $225 million at the time, although DOE told me today that it has so far committed $101 million to the five-year B&W project through March 2014 and that it is currently reviewing the release of additional funds.

“Small modular reactors represent a new generation of safe, reliable, low-carbon nuclear energy technology,” U.S. Energy Secretary Ernest Moniz said in announcing the award to NuScale. “The Energy Department is committed to strengthening nuclear energy’s continuing important role in America’s low carbon future.”

SHRINKING CONVENTION

Like B&W, the NuScale design calls for a scaled-down conventional reactor, fueled by solid uranium, cooled by ordinary water and operated in a pressurized environment. By virtue of its smaller size, the NuScale “Integral Pressurized Water Reactor” (IPWR) portends lower costs because in principle it could be factory-built in more of an assembly line manner than could large conventional reactors; the idea is to ship them to a site via truck, rail or barge for final assembly. The “integral” design fits a reactor and a steam generator in an 80-foot by 15-foot cylinder.

The small size would also allow users such as utilities to purchase new reactors in less expensive increments rather than paying billions of dollars up front for conventionally sized reactors, which reach well over a gigawatt in electrical capacity. At 45 megawatts electric, the NuScale reactor provides about 3 percent the output of a 1.3-GW reactor. NuScale’s “modular” design permits up to 12 of the pressurized water reactors in a plant, for a total capacity of 540 MW.

NuScale, founded in 2007, has designed the IPWR to sit underground, thus protecting it from attack. The IPWR deploys a “passive cooling” system that would release a pool of water from above the reactor in the event of an emergency, rather than rely on pumps to circulate water (failed auxiliary electricity systems knocked out cooling at Japan’s Fukushima reactor, leading to meltdowns there).

EYEING IDAHO

NuScale partner Energy Northwest, a Richland, Wash. company that produces power for utilities, said that NuScale could develop a commercial six-to-12-reactor plant on the site of Idaho National Laboratory by 2024, which Energy Northwest would have the right to operate. Utah Associated Municipal Power Systems, a cooperative of government entities that pools electrical power resources, is also part of the scheme.

U.K. engineering stalwart Rolls Royce is also part of the NuScale small modular project. NuScale is majority owned by $27.6 billion engineering company Fluor Corp., based in Irving, Texas.

The presence of several companies in the NuScale project echoes the B&W small modular reactor venture which won the first tranche of DOE’s $452 million in SMR funding. B&W is working with U.S. construction firm Bechtel, and with federal power provider Tennessee Valley Authority. They hope to deploy four 180-MW reactors at TVA’s Clinch River, Tennessee site, via a joint venture called Generation mPower that is 90 percent owned by B&W and 10 percent by Bechtel.

That project took a peculiar turn recently, when B&W said it plans to sell 70 percent of its interest in mPower – including intellectual property.

A DOE spokeswoman said that DOE has so far committed $101 million to B&W through March, 2014. Possible further funding is currently under review, she said. B&W’s five-year federal funding period began in December, 2012. If DOE released more funds, the total would not exceed $226 million, the same five-year cap on the NuScale funding, which runs through Dec. 2018. In both cases, DOE would also be limited to funding no more than half of project costs, the spokeswoman said. She added that there will be no more grants under the $452 million Funding Opportunity Announcement (FOA).

CAN’T TAKE THE HEAT

While the DOE grant helps to push U.S. nuclear in a new direction of smaller and less expensive reactors, it stopped short of endorsing altogether new reactor designs that would support much higher operating temperatures.

These so-called “fourth generation reactors” include liquid fuel reactors known as molten salt reactors, as well as solid fuel reactors using “pebble bed” and “prismatic” fuel structures rather than conventional rods.  They would provide many additional advantages. For instance, they typically operate in unpressurized environments, which is a safety benefit over today’s pressurized reactors. They tend to leave less long-lived waste.

At higher temperatures they also generate electricity more efficiently, which lowers generating costs and would help nuclear compete in a market where natural gas prices are currently low. Unlike natural gas generation, nuclear power generation is carbon free, and the nuclear lifecycle is low-carbon.

And as Secretary Moniz himself noted last month, high temperature reactors could serve as sources of low-carbon heat for industrial processes and thus expand nuclear power beyond its role of generating electricity.

A number of high temperature reactor developers vied for the DOE award that went to NuScale, including San Diego’s General Atomics, and X-Energy Inc., a Greenbelt, Maryland-based company that is developing a pebble bed reactor based on older South Africa designs.

Stay tuned to the Weinberg site as we delve into some of these alternative reactor designs in our upcoming blog posts.

Photo is from NuScale via ChenectedAiche

Negotiations about Iran's nuclear plans

By U.S. Department of State from United States [Public domain], via Wikimedia Commons

The recent agreement between six world powers and Iran has, according to President Obama; “cut off Iran’s most likely paths to a bomb”The agreement includes many commitments to cease enrichment of uranium above concentrations of 5%, dismantling or halting construction of additional centrifuges and a pledge to not construct a reprocessing facility. Iran will continue to enrich uranium to concentrations of 3.5% to keep its stocks at a constant level as it is consumed in the civilian nuclear power program.  

However, much of the discussion about the deal has missed one key question: the extent to which we are made prisoners by the proliferation risks of existing fuel cycles. Could a programme of nuclear R&D, aimed at developing proliferation-resistant nuclear energy, prevent future nuclear crises?

What if we said that no enrichment facilities would be necessary if Iran was planning on producing nuclear energy with a thorium fuel cycle?

Thorium sits two places down the periodic table from uranium, and while very little of naturally occurring uranium is the U235 necessary for use in a reactor, almost all of naturally occurring thorium is Th232, which is the isotope suitable for use as a nuclear fuel. . Because of this, there is no need for any enrichment of thorium fuel and no need for centrifuges of any kind. The lack of any need for these facilities would certainly change the game in terms of detecting rogue nuclear programmes.

However, there is a “but”: thorium fuels need a “fissile driver” to provide the initial neutrons to start the thorium chain reaction. This can be uranium-233, uranium-235 or plutonium, although for anti-proliferation purposes we should certainly discount the last two.

So that leaves us with U233. Handily, uranium-233 is produced by thorium fuels in a reactor (in a thorium fuel cycle, it is actually uranium-233 that fissions). The rub is that the world has very little U233 available and if we want to develop proliferation-resistant fuel cycles, we’ll need a lot more of it. Currently the only way to make it is to kickstart thorium fuel with…U-235 or plutonium, and then reprocess it (although Accelerator-Driven Systems could help).

Proliferation resistance

While U233 is recognised as a proliferation risk by the IAEA, it is far less suitable for making weapons than highly enriched U235 or Pu239. Indeed, only two nuclear tests have involved U233; the USA’s ‘Operation Teapot’and one 0.2kt experimental design in India’s Pokran-II tests. No nuclear weapons in existence are made with U233. Sadly uranium-235 and plutonium have a well-proven track record of making functioning bombs.

U232 is produced in smaller amounts alongside the U233, which is a hard gamma ray emitter. This gives the material a strong and easily detectable radiation signature. The material has to be handled very carefully, and fuel fabrication for example has to be done remotely with sophisticated equipment. These increased difficulties have long been cited as  properties that would hinder weapons proliferation.

Hans Blix, the former head of the International Atomic Energy Agency has recently called for the development of nuclear energy from thorium, citing a lower risk of weapons proliferation from reactors as well as benefits including reduced waste. He wrote in the Guardian newspaper that the commitments were “constitute substantial bars to any bombmaking” without curtailing the civilian power program. I’m sure he would agree that if Iran was pursuing thorium-fuelled reactors, the barriers to a weapons program would be even higher.

Of course, how any future international thorium fuel programme would obtain and distribute the “fissile drivers” would be very sensitive, needing just the kind of increased transparency and oversight that has just been agreed. What is certain is that proven thorium fuels, started with U233, would give the international community new diplomatic options in future nuclear disputes.

The nuclear club is expanding

Thirty-one of the world’s countries currently use nuclear power to generate over 11% of global electricity. Over forty-five countries are considering embarking down the nuclear route, with the front-runners after Iran and UAE including Lithuania, Turkey and Belarus. It is important to stress that thorium is not a magic bullet to weapons proliferation– but it can be a part of the solution to future international proliferation disputes, alongside appropriate regulatory regimes and oversight mechanisms. Given the pressing need for low-carbon energy it seems only prudent to support a more proliferation-resistant route for nuclear energy.

The MegaTons to MegaWatts program which saw almost 20,000 Russian warheads dismantled and used as fuel in American nuclear power plants has recently come to an end, providing almost 10% of US electricity for 15 years. A similar amount of warheads remain in existence. In 1953, Eisenhower’s ‘Atoms for Peace’ speech carefully tried to open the eyes of the world to the positive benefits of nuclear energy, after the horrors of the nuclear bomb had become clear. He urged that “the miraculous inventiveness of man shall not be dedicated to his death, but consecrated to his life”. Perhaps it is time for that speech to be revisited, starting with a massive push to develop proliferation-resistant nuclear energy.

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