tag:blogger.com,1999:blog-91305140053288173062024-03-07T04:16:28.473-05:00Pebble Bed ReactorSolving the US Energy CrisisRobert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.comBlogger25125tag:blogger.com,1999:blog-9130514005328817306.post-52760435838188337492012-08-04T13:42:00.001-05:002012-08-04T13:42:09.852-05:00THORIUM: energy cheaper than coalTHORIUM: energy cheaper than coal is a new book about two energy technologies that can solve global warming, sustainability, and energy poverty. Energy cheaper than coal is the only realistic way to dissuade 7 billion people in 250 countries from burning coal to make electricity. Thorium and the molten salt reactor provide the means to manufacture liquid fluoride thorium reactors (LFTR) at a Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com0tag:blogger.com,1999:blog-9130514005328817306.post-57458133594219664222010-03-24T05:42:00.002-05:002010-03-24T05:53:31.751-05:00US Dept of Energy saves pebble bed reactor projectSouth Africa Pebble Bed Modular ReactorSouth Africa's Pebble Bed Modular Reactor company has been thrown a $10-million lifeline by the US Department of Energy only a week before its government funding runs out.But it will not be enough to prevent the retrenchment of three-quarters of the PBMR's 800 staff and the reduction of its executive team from 11 to three. CEO Jaco Kriek resigned earlier Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com3tag:blogger.com,1999:blog-9130514005328817306.post-26880593365465714442009-02-20T08:46:00.007-05:002009-02-20T09:27:05.188-05:00Aim High -- Thorium energy cheaper than from coalLiquid Fluoride Thorium ReactorThe liquid fluoride thorium reactor is another advanced nuclear power source, even more promising than the pebble bed reactor. The LFTR uses inexpensive thorium as a fuel, transforming it to uranium-233 which fissions, producing heat and electric power at a cost less than that from coal power plants.Thorium and uranium are dissolved in molten salt, simplifying Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com16tag:blogger.com,1999:blog-9130514005328817306.post-42687826741590746722009-02-20T07:55:00.004-05:002009-02-20T08:11:17.474-05:00PBMR to run out of cash in 2010Conceptual layout of a PBMRJohannesburg's Business Report says the pebble bed modular reactor project is running out of cash. It's initial goals may have to be redirected.One way to obtain an early benefit from the PBMR is to use its heat directly, deferring the development of the helium turbine and electric generator. South Africa's SASOL company is the largest producer of gasoline from coal. Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com3tag:blogger.com,1999:blog-9130514005328817306.post-56772064325974913152008-04-12T06:36:00.006-05:002008-12-09T20:00:42.310-05:00UConn prof writes clear PBMR overviewPelindaba, South Africa, pebble bed work siteProfessor Lee Langston writes in Mechanical EngineeringUniversity of Connecticut retired professor Lee Langston has just published a very clear, readable history of the pebble bed modular reactor project underway in South Africa. Pebbles Making Waves is the feature article in the April, 2008, issue of Mechanical Engineering, published by the American Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com5tag:blogger.com,1999:blog-9130514005328817306.post-48353494053897493072008-03-19T12:23:00.005-05:002008-12-09T20:00:42.430-05:00Pebble fuel grains pass performance testingINL Advanced Test Reactor test siteAn earlier post described the start of testing of the multiple-layer-coated fuel grains that form the billiard-ball-sized fuel pebbles in the pebble bed reactor. Idaho National Laboratory used its Advanced Test Reactor to expose these test fuel grains to radiation levels much higher than in an operational PBR, thus simulating years of exposure in a few months. Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com20tag:blogger.com,1999:blog-9130514005328817306.post-32929683010538148942008-03-04T13:02:00.009-05:002008-12-09T20:00:42.540-05:00Energy Policy and Environmental Choices: Rethinking Nuclear PowerWill the public rethink nuclear power?I have not posted anything to this blog about pebble bed reactors for months. I have been busy developing a way to educate the general public about the broader issues of nuclear power.Most people to whom I have presented the pebble bed reactor have been encouraging and supportive. The most common query I receive is "what about the waste?".I now think public Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com5tag:blogger.com,1999:blog-9130514005328817306.post-42909479936481600602007-04-13T13:00:00.000-05:002008-12-09T20:00:42.606-05:00Nuclear powered cars are emissions free or or Some ways to generate electricity for electric carsElectric cars are emissions free, unless the electric power they use comes from coal power plants. Electric cars are becoming available, and more are planned.2010 Chevrolet Volt Electric VehicleChevrolet will produce the Volt EV in the 2010-2012 time frame. It is powered by electricity from batteries that will allow the car to travel 40 Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com4tag:blogger.com,1999:blog-9130514005328817306.post-60922232655688922192007-04-07T18:00:00.000-05:002008-12-09T20:00:42.628-05:00Germany built the first pebble bed reactorDemonstration of inherently safe AVR shutdownThe pebble bed reactor is an intrinsically safe because the chain reaction diminishes as the fuel temperature rises. This has been demonstrated. The experimental Arbeitsgemeinschaft Versuchsreaktor (AVR) was built in Germany in 1960. Dr. Rudolf Schulten was the originator of the pebble bed reactor design. The experimental AVR at the Julich Research Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com3tag:blogger.com,1999:blog-9130514005328817306.post-29793524205759364342007-03-30T17:31:00.000-05:002008-12-09T20:00:42.909-05:00China has built a pebble bed reactorHTR-10 at China's Tsinghua UniversityChina's Tsinghua University has built a 10 MW research pebble bed reactor, achieving criticality in 2000. HTR-10 stands for High Temperature gas-cooled Reactor of 10 Megawatts heat output. It is cooled by helium gas. The helium gas today powers a steam generator. Currently the faculty and students are designing a power conversion unit to be driven directly by Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com5tag:blogger.com,1999:blog-9130514005328817306.post-81749152278491878622007-03-25T09:00:00.000-05:002008-12-09T20:00:43.454-05:00South Africa is planning a Pebble Bed ReactorPBMR vessel, turbines, and generatorThe Pebble Bed Modular Reactor (PBMR) is the terminology for South Africa's specific pebble bed reactor project and company. Pebble Bed Modular Reactor (Pty) Ltd has designed and is building a single module demonstration pebble bed reactor with a capacity of 165 MW. Assuming regulatory approvals, the demonstration plant will begin construction in 2008 with the Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com2tag:blogger.com,1999:blog-9130514005328817306.post-56602743468530723672007-03-17T10:27:00.002-05:002008-12-09T20:00:44.013-05:00Idaho National Laboratory would build the first US PBRINL Very High Temperature ReactorIn the hospital waiting room last week I was astonished to find the January 2, 1989, copy of Time magazine. Time described an "inherently safe...heat-resistant ceramic spheres...cooled by inert helium gas" reactor to be built by the US government in Idaho Falls. This pebble bed reactor project has been awaiting funding for at least 18 years.The 1989 Time magazine Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com2tag:blogger.com,1999:blog-9130514005328817306.post-82247910990381525912007-03-11T14:27:00.000-05:002008-12-09T20:00:44.764-05:00Compare Coal Power to PBR Nuclear PowerTrainloads of coal power the US electric gridA typical 1,000 megawatt coal fired electric plant burns a mile-long train of coal every day. Burning these 11,000 tons of carbon fuel creates 3.6 times as much carbon dioxide, because each C12 binds to two O16 atoms. If we were to capture all that carbon dioxide, refrigerate and liquefy it, it would fill a train of refrigerated tank cars over 3 1/2 Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com7tag:blogger.com,1999:blog-9130514005328817306.post-70175364742211537582007-03-02T15:00:00.000-05:002008-12-09T20:00:45.255-05:00Nuclear Oil is an antidote to the Peak Oil BlightOil production outside OPEC and former USSRPeak Oil is a name given to a concept of resource depletion. The 2004 US DOE chart above illustrates that in Texas oil was first pumped from the earth in 1934. Texas oil production rose and then began falling as the oil was depleted more rapidly than discovered. Peak oil happened in 1971 in Texas. As oil runs out in one area of the world, further Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com0tag:blogger.com,1999:blog-9130514005328817306.post-79889111114587932312007-02-22T00:35:00.000-05:002008-12-09T20:00:45.527-05:00Pebble bed reactors can supply hydrogen for power The hydrogen economy is a futuristic vision of our society using hydrogen for vehicle fuel. Hydrogen can burn in an internal combustion engine creating only water vapor, H2O, which is nonpolluting and does not contribute to global warming.However, hydrogen is a very reactive element and on earth hydrogen is bound up in molecules, principally water, H2O. To create pure H2 the hydrogen must be Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com1tag:blogger.com,1999:blog-9130514005328817306.post-10275080057472227692007-02-16T16:10:00.000-05:002008-12-09T20:00:45.923-05:00Corn ethanol energy is a delusional diversionEthanol from corn is being hailed as a carbon-neutral fuel for automobiles. The CO2 emitted from from ethanol combustion is balanced by CO2 absorbed in growing the corn. Corn ethanol is also promoted as reducing US dependence on imported petroleum for gasoline.It takes a lot of energy besides sunlight to produce ethanol. Energy is needed for transportation, fertilizers, fermentation, and refiningRobert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com3tag:blogger.com,1999:blog-9130514005328817306.post-30984285489404929552007-02-09T16:33:00.000-05:002008-12-09T20:00:46.310-05:00PBRs can halve global warming CO2In February, 2007, the Intergovernmental Panel on Climate Change published the report Climate Change 2007 which gave further evidence that (a) the climate is warming, and (b) human activities are part of the cause. Most of the press coverage focuses on the warming, the shrinking glaciers, starving polar bears, and rising oceans. The evidence that man-made greenhouse gasses actually cause the Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com2tag:blogger.com,1999:blog-9130514005328817306.post-40081360405395194052007-02-03T12:30:00.000-05:002008-12-09T20:00:46.581-05:00Technology has improved since 1970s nukesThree dimensional computer aided design technologies help designers lay out and test designs for products ranging from tiny heart stents to huge airliners. Above is another presentation of the conceptual PBR layout done by MIT researchers using such tools. Some of the Seabrook cost overruns were due to design errors, which caused piping runs to collide during construction. With today's 3D-CAD Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com1tag:blogger.com,1999:blog-9130514005328817306.post-34716041333438906302007-01-27T14:00:00.000-05:002008-12-09T20:00:46.959-05:00Factory-build PBRs, ship, and assemble on siteA pebble bed reactor unit can be assembled within a containment building approximately 25 x 40 meters in size. Such a unit would generate approximately 100 megawatts, at a capital cost of roughly $200 million. Most large coal or nuclear electric power plants in the US are much larger, about 1,000 megawatts. An advantage of the relatively smaller PBR unit is that the modules can be grouped and Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com2tag:blogger.com,1999:blog-9130514005328817306.post-85770520351721584222007-01-20T12:00:00.000-05:002008-12-09T20:00:47.544-05:00MIT drives much pebble bed reactor researchMIT, the Massachusetts Institute of Technology, is a great institution. For example, the MIT Department of Nuclear Science and Engineering has led the study of basic nuclear processes and nuclear engineering for a half century. In light of the fact that the US has not built a nuclear power plant since the 1970s, we are fortunate that the science lives on with in faculty of 28 and senior research Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com7tag:blogger.com,1999:blog-9130514005328817306.post-50538814534011993152007-01-14T08:44:00.000-05:002008-12-09T20:00:48.597-05:00PBR passive safety comes from basic physicsThe uranium fuel in the pebble bed reactor can not melt down. The nuclear chain reaction slows down as the temperature rises.Naturally occurring uranium contains two isotopes, 0.7% U235 and 99.3% U238. The fissionable U235 in the fuel spheres is enriched to exceed 3% so that a chain reaction can be sustained. As a U235 atom nucleus decays it releases neutrons and creates heat. The neutrons bounceRobert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com3tag:blogger.com,1999:blog-9130514005328817306.post-86661072104340690462007-01-10T09:11:00.000-05:002008-12-09T20:00:48.922-05:00Pebbles circulate within the reactorThe reactor vessel is about 50 feet high and 15 feet in diameter, containing approximately 360,000 fuel pebbles. Pebbles are introduced at the top and flow down and out at a rate of 3,000 per day. As each fuel pebble is removed it is examined to determine how much of the fuel has been used up. After a few years to reach steady state operation about 350 pebbles will be replaced daily with fresh Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com1tag:blogger.com,1999:blog-9130514005328817306.post-53391729704067413812007-01-03T08:30:00.000-05:002008-12-09T20:00:49.093-05:00Pebbles contain the products of radioactive decayPebbles contain thousands of coated particles of UO2Each fuel sphere, or "pebble" is a bit smaller than a tennis ball and contains many small particles of uranium oxide, which is the fuel for the nuclear reactor. Each fuel particle is wrapped in several layers of ceramic carbon and silicon carbide. The first layer of porous pyrolytic graphite absorbs the radioactive xenon gas emitted when the Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com0tag:blogger.com,1999:blog-9130514005328817306.post-32752688448184798162006-12-23T18:38:00.000-05:002008-12-09T20:00:49.220-05:00PBR advantages are attractivePebble bed reactor fuel spheres1. Pebble bed reactor (PBR) technology is safe; the reactor can not melt down. While today's reactors are safe due to multiple, redundant, engineered shutdown, cooling, and containment systems, the PBR is safe because the basic physics increases neutron absorption if the temperature rises.2. PBR’s are cooled by helium gas, which is chemically inert and not Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com11tag:blogger.com,1999:blog-9130514005328817306.post-84842249192732552622006-12-21T10:10:00.000-05:002008-12-09T20:00:49.901-05:00We can solve the US energy crisisMIT pebble bed reactor drawingThe United States has an energy crisis, incorporating energy costs, global warming, and national security. A pebble bed reactor is a nuclear power plant that can generate electricity and hydrogen, eliminate carbon emissions, and cut US dependency on unstable oil producing nations.We'll introduce the pebble bed reactor in more detail later. Now let's recap some facts Robert Hargraveshttp://www.blogger.com/profile/06846491141058940965noreply@blogger.com1