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April 15, 2012

Carnival of Nuclear Energy 100

Carnival of Nuclear Energy 100 is up at Atomic Power Review

Nuke Power Talk -
At Nuke Power Talk, Gail Marcus takes on the claim
that is beginning to circulate that "after all, Japan survived for a year without nuclear power, so it doesn't need its nuclear plants." She points out several factors that show 1) that there were a number of serious effects on the economy, and on the population, from the reduced electricity supply, and 2) there are several factors that could make next summer much worse

1. Last summer, some of the nuclear power plants in Japan were still in operation. This coming summer, most or all plants will be shut down, so there will be less power available than last summer.

2. According to reports, Japan was fortunate that it did not experience an exceptionally hot summer. A hotter than average summer would increase the demand for energy

3. Japan managed its crisis in part by ramping up its use of old thermal power plants. This has increased the levels of carbon emissions and other fossil fuel air pollution. Prolonged reliance on an increased use of older fossil fuel plants is likely to result in chronic illnesses and even deaths in some segments of the population.

4. The cutbacks in power caused discomfort and inconvenience--or worse--for much of Japan's population. I have not seen any statistics on deaths due to heat stroke, but I suspect there were some, and others are also predicting that there could be more problems.

5. The reduced energy supply affected Japan's economy. Continued reductions in energy supply will prolong the effects on the economy. With the shutdowns of Japan's nuclear power plants, factory production was reduced or moved to lower-demand periods.

Nuclear Green - More on the Denatured Molten Salt Reactor from David LeBlanc

The Denatured Molten Salt Reactor (DMSR) is probably the simplest Molten Salt Reactor (MSR) design. The DMSR concept was first proposed by T.J.Burns et al, in ORNL 5388, Interim Assessment of the Denatured 233UFuel Cycle: Feasibility and Nonproliferation Characteristics. A second document, ORNL TM/TM 7202, CONCEPTUAL DESIGN CHARACTERISTICS OF A DENATURED MOLTEN-SALT REACTOR WITH ONCE-THROUGH FUELING, offered further insight into the ORNL concept.

Several previous cost estimates of power production for MSBR type reactors have always been very favorable in comparison to LWR or coal. With the far simpler DMSR which needs no capital and O&M costs for fuel processing the advantage should be even greater. As no fabrication of fuel elements is required and only minor chemical control are needed, fuel cycle cost at present uranium and SWU prices would be only 5 to 6 million per GWe year or under 1 mill/kwh (0.1 cent/kwh), compared to about 50 million for LWR. The start up fissile capital costs are far lower as well (3.5 t 235U for DMSR and no fabrication versus 5 t for PWR plus fabrication or roughly 100 million versus almost 200 million)

While a molten salt reactor does require the expense of an intermediate loop (like a sodium cooled fast reactor) there are numerous areas for major savings. Most come down to the fact that the reactor is so inherently safe. Something like a pump failure is an inconvenience, not a safety issue so components do not require multiple backups and the highly engineered “defense in depth” approach of solid fueled reactors.

The overall thermal efficiency of the plant is also much higher. 1970s versions expected 44.4% with a supercritical steam cycle. With salt inlet/outlets of 565C/705C modern ultra supercritical steam cycles closer to 50% would be possible which would be far more economically attractive than the low efficiency, saturated steam of LWR and CANDU turbines. As well, molten salt reactors are an ideal match to gas brayton cycles, such as multi reheat helium or supercritical carbon dioxide also reaching close to 50%. Gas turbine options offer large cost and rapid production advantages but as seen in recent South African efforts, establishing a “first of kind” turbine is a large hurdle even when the advantages of the “nth” turbine are so attractive. Thus the ability to match well to both steam or gas is a large advantage.

Dr Leblanc argues, it is not unreasonable to assume that capital costs could be 25% to 50% less for a simple DMSR converter design than for modern LWRs



Nuke Power talk - experts are beginning to recognize that it is not enough to protect against damaging levels of radiation exposure to the public. We must consider how to protect against extensive land and water contamination and to mitigate against the consequences of contamination levels that require long-term evacuation and the indefinite sequestration of large areas of land.

Idaho Samizdat - Two recent nuclear energy start-ups have the potential to create new business opportunities with unconventional reactor technologies. Two of them are pursuing new designs using molten salts as compared to the conventional light water design.

In Massachusetts, Transatomic Power, run by two Ph.D. candidates at MIT, Leslie Dewan and Mark Massie, the effort is focused on using uranium-based spent nuclear fuel to provide the energy to run the reactor. Their business model is to license a design to a major reactor vendor or a state-owned reactor development agency.

In Alabama, Flibe Energy, named after an acronym for a a specific type of salt, is run by Kirk Sorensen who after earning a masters degree in nuclear engineering, jumped out of the corporate world to develop a start-up effort aimed at producing a thorium-fueled reactor for military applications.


Nextbigfuture - Japan has all approvals but local consent to restart two reactors. Trade Minister Yukio Edano also said that he will visit Fukui prefecture, host to the No. 3 and No. 4 reactors at Kansai Electric Power Co's Ohi nuclear power plant, on Saturday to meet with the governor and Ohi town mayor and to convince them of the necessity for the restarts. Edano set no deadline for the reactor restarts, but implied that he hopes to obtain public backing by July, when the hottest season starts.

Nextbigfuture - Total nuclear electricity generation in 2011 was 2518 TWh, 4.3% less than the 2630 TWh generated in 2010, according to figures from the International Atomic Energy Agency (IAEA). Generation had increased in 2010 following three consecutive years of decline. Japan's generation was down 127.7 TWh and world generation was down 112 TWh. Germany shutdown reactors for another 30.7 TWh decrease. So the world generated 46.4 TWh more if the effect of Japan and German shutdowns were excluded. Looking at 2012, generation will increase from 14 new nuclear reactors.

Nextbigfuture - Maxing out technology (including nuclear power) for 2027-2032. I am expecting several possible technology for an energy revolution to be proven over the next 5 years. Candidates energy technologies are advanced modular fission reactors, new hot nuclear fusion technology, or breakthrough low energy nuclear reactors.

Annular fuel (hollow cylinders with pebbles for more surface area) enables existing nuclear reactors to generate 20-50% more power. South Korea is working on developing the MIT research for commercial installation in about 2020. The company Lightbridge is developing the fuel and could have wide deployment by the early 2020s.


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