Is our desire for an endless supply of clean energy enough to open our eyes to new business models and new technologies? Ask Kirk Sorensen, Chief Nuclear Technologist for Teledyne Brown Engineering, Co-Founder of Flibe Energy (“Flibe”), and speaker at this year’s Global New Energy Summit (www.globalnewenergysummit.org) in Colorado Springs, and I believe that he’d say that we should keep an open mind about nuclear power and in particular, Thorium. Flibe was founded on technology to use Thorium as a nuclear fuel to create energy. Thorium is natural, abundant and inexpensive. Indeed, Thorium is common in the Earth’s crust, approximately three to four times more common than Uranium. Thorium energy can be inexpensive and clean if made by a liquid-fluoride thorium reactor (LFTR), pronounced “lifter.”
The primary concern with the traditional approach to nuclear power generation is the use of low-enrichment uranium (LEU) in solid-uranium-oxide-fueled light-water reactors. These reactors produce significant plutonium from the uranium-238 that makes up 95-97% of the original fuel. Irradiation produces by-products including other isotopes of plutonium called transuranic nuclear waste. After years of irradiation, spent fuel rods are stored in repositories to move towards stability. Reducing the amount of transuranic waste is critical for nuclear power generation. According to Sorensen, by using Thorium in a fluoride reactor as opposed to uranium in a solid-oxide reactor, it is possible to reduce the amount of transuranic material generated by a very large factor.
Thorium and the fluoride reactor present an entirely different model. The primary difference is that the thorium is in the liquid fluoride form and is therefore chemically stable. Only products that are generated during operation are removed and the fluid can be continually reused. The ability to reuse is a profound advantage.
Nuclear energy however, can’t be mentioned without addressing safety concerns. So how does Thorium compare? Sorensen is very outspoken about the safety record of the nuclear industry and emphasizes that the safety record in the nuclear industry is unparalleled. That safety record, however, is purchased at a price because the safety systems are engineered. LFTR on the other hand, is passively safe in case of an accident. In simple terms, the LFTR is equipped with a frozen plug, kept frozen by an external cooling fan. In the event of failure, the freeze plug in the reactor melts and allows the core salt to drain into a passively cooled configuration where nuclear fission and meltdown are not possible.
Flibe Energy is currently leading the charge in the design of LFTR technology. They have proposed to design, develop and demonstrate a small modular liquid-fluoride thorium reactor (SM-LFTR) for the U.S. Military having a design power level of 20-50 MWe. According to Sorensen, “the SM-LFTR is the precursor to much larger, utility-class LFTRs operating at the 250-300 MWe power generation scale.” Flibe further envisions production of modular units with capital costs in-line with gas turbines.
The benefits to implementation of LFTR technology are seemingly overwhelming. The technology has relatively small land use footprint compared to energy output, Thorium is abundant and we don’t need much (according to Sorensen a small grain silo of Thorium could power North America for a year and known Thorium reserves could power society for thousands of years), and the technology has built in passive safety – just to name a few benefits. In addition, however, while LFTR can produce safe, sustainable electricity, lifesaving medical radioisotopes, desalinated water and ammonia for agriculture and synthesized fuels are produced in the process. In other words, LFTR technology could have other impacts in global energy, medical, agricultural and industrial sectors.
What I haven’t mentioned is that this work is based on Alvin Weinberg’s vision of our energy future as director of the Oak Ridge National Lab from 1955 to 1972. It’s not a new concept. Moreover, the Department of Energy has put the burden on industry to lead in the design, development, and implementation of new nuclear energy according to market principles. As attorneys that work with industry to overcome barriers to successful commercialization of emerging technology, we recognize that there are challenges - whether regulatory or otherwise, to deployment and market integration, no matter what the solution is and what the benefits are. We look forward to learning more about Flibe Energy and next steps for private industry at the Global New Energy Summit in Colorado Springs, Colorado, April 9-11, 2012. To find out more go to http://www.globalnewenergysummit.org/.
The People’s Republic of China has initiated a research and development project in Thorium Fueled Molten Salt Reactor (TFMSR) technology. This project was announced at the Chinese Academy of Sciences annual conference on Tuesday, January 25, 2011. Led by Dr. Jiang Mianheng, a doctoral graduate of Drexel University in electrical engineering, the new TFMSR program aims not only to develop the technology, but also to secure intellectual property (patent) rights to its implementation. Chinese R&D is a clear and important endorsement of the benefits of TFMSR’s. Let’s take a moment to review these benefits.
ReplyDelete* Safe * -- cannot melt down ("meltdown" is the standard operating condition); operates at ambient pressure (no pressure, no explosions); the passive emergency shutdown system is operated by gravity -- no human intervention required (walk-away safe); burns nuclear plant waste (spent fuel rods) and plutonium from atomic weapons.
* Clean * -- no CO2 emissions; no proliferation; .004 as much mining waste as uranium; .001 as much nuclear waste as uranium; 10-year storage for .00083 of the equivalent uranium waste; 300 years for .00017 of the equivalent uranium waste.
* Proven * -- successful operation for over 5 years at Oak Ridge National Labs in their Molten Salt Reactor Experiment.
* Efficient * -- continuous refueling; continuous waste processing; nearly 100% fuel consumption; nearly 50% thermal/electric conversion; cheaper than coal and natural gas.
* Affordable * -- no high-pressure containment required; no thorium enrichment required; can be air-cooled (no redundant cooling systems required); estimated $10,000 annual fuel cost for One Gigawatt of electric power; .01 as much power plant land area, and no buffer zone are required
* Plentiful Fuel * -- thorium is abundant (400% more than uranium worldwide); high energy density -- one ton of thorium is equivalent to 200 tons of uranium, or to 3,500,000 tons of coal.
Few people understand how many problems our current reactors have are from using water to cool them.
ReplyDeleteMolten-salt reactors use no water (a special salt is the coolant). The coolant can't boil, so there's no high pressure, no risk of "loss of coolant accidents"; no water so no risk of steam or hydrogen explosions.
Molten-salt reactors have inherent safety, much better than LWR engineered safety.
Another big benefit of a molten-salt reactor such as LFTR is it could use nuclear waste from a light water reactor (LWR, the type of almost all reactors in the world) as fuel, 800kg of uranium/plutonium to make 1 gigawatt electricity for a year. It's the uranium and plutonium (and other transuranic elements) that have to be stored so long. Since an MSR consumes 99%+ of the uranium/plutonium, waste is much easier to take care of -- nothing to somehow safely store for 100,000+ years.
Without having uranium to store, the fission byproducts with short half-lives would be harmless in under 10 years (83% of the total fission byproducts have half-lives well under 1 year). The rest (17%) would be safe in 350 years.
In a LFTR, these are easily separated, and stored. We know how to safely store 135kg (300 lbs) of waste for 350 years, per gigawatt-year electricity generated.
See http://liquidfluoridethoriumreactor.glerner.com/ for what they are, how they're different, what ways they are so much safer, how they can consume nuclear waste, how they would fare in accidents or terrorist attacks, how much less they would cost, how long it will take us to build them.