Global support for nuclear energy drops after Fukushima

Originally posted by AGWskeptic
From what I've been reading Molten Salt Reactors are both safe to operate and generate very little waste.

But they don't help with weapon manufacturing, so the technology was shelved.

Molten Salt Reactors also can't ever go into meltdown.

I'm no expert, so I'd love to hear from someone more familiar with these MSR's.

One unexpected finding was shallow, inter-granular cracking in all metal surfaces exposed to the fuel salt. The cause of the embrittlement was tellurium - a fission product generated in the fuel. This was first noted in the specimens that were removed from the core at intervals during the reactor operation. Post-operation examination of pieces of a control-rod thimble, heat-exchanger tubes, and pump bowl parts revealed the ubiquity of the cracking and emphasized its importance to the MSR concept. The crack growth was rapid enough to become a problem over the planned thirty-year life of a follow-on thorium breeder reactor. This cracking could be reduced by adding small amounts of niobium to the Hastelloy-N.

After shutdown the salt was believed to be in long-term safe storage, but beginning in the mid-1980s, there was concern that radioactivity was migrating through the system. Sampling in 1994 revealed concentrations of uranium that created a potential for a nuclear criticality accident, as well as a potentially dangerous build-up of fluorine gas — the environment above the solidified salt is approximately one atmosphere of fluorine. The ensuing decontamination and decommissioning project was called "the most technically challenging" activity assigned to Bechtel Jacobs under its environmental management contract with the U.S. Department of Energy's Oak Ridge Operations organization. In 2003, the MSRE cleanup project was estimated at about $130 million, with decommissioning expected to be completed in 2009.

The half-life of thorium-232 is about 14.05 billion years. It is estimated to be about three to four times more abundant than uranium in the Earth's crust.

- much cleaner: as a full recycle system, the discharge wastes from the reactor are predominately fission products, most of which have relatively short half lives compared to longer-lived actinide wastes.
- This can result in a significant reduction in the containment period in a geologic repository (300 years vs. tens of thousands of years) can "burn" some problematic radioactive waste (with transuranic elements from traditional solid-fuel nuclear reactors)

Waste--In theory, LFTRs would produce far less waste along their entire process chain, from ore extraction to nuclear waste storage, than LWRs. A LFTR power plant would generate 4,000 times less mining waste (solids and liquids of similar character to those in uranium mining) and would generate 1,000 to 10,000 times less nuclear waste than an LWR. Additionally, because LFTR burns all of its nuclear fuel, the majority of the waste products (83%) are safe within 10 years, and the remaining waste products (17%) need to be stored in geological isolation for only about 300 years (compared to 10,000 years or more for LWR waste). Additionally, the LFTR can be used to "burn down" waste from an LWR (nearly the entirety of the United States' nuclear waste stockpile) into the standard waste products of an LFTR, so long-term storage of nuclear waste would no longer be needed.

Safety--LFTRs are designed to take advantage of the physics of the thorium cycle for optimum safety. The fluid in the core is not pressurized, thus eliminating the driving force of radiation release in conventional approaches. The LFTR reactor cannot melt down because of a runaway reaction or other nuclear reactivity accidents (such as at Chernobyl), because any increase in the reactor's operating temperature results in a reduction of reactor power, thus stabilizing the reactor without the need for human intervention. Further, the reactor is designed with a salt plug drain in the bottom of the core vessel. If the fluid gets too hot or for any other reason including power failures, the plug naturally melts, and the fluid dumps into a passively cooled containment vessel where decay heat is removed. This feature prevents any Three Mile Island-type accidents or radiation releases due to accident or sabotage and provides a convenient means to shut down and restart the system quickly and easily.

MOSCOW — Russia's nuclear power plants are dangerously under-prepared for earthquakes and other disasters, said a state review conducted after Japan's Fukushima accident and obtained Thursday by AFP.

The unusually candid survey was presented to a council chaired by President Dmitry Medvedev on June 9 and initially reported on its website by the Oslo-based Bellona environmental organisation. Russia has until now steadfastly defended its 10 nuclear power plants and 32 reactors against criticism.

Prime Minister Vladimir Putin on April 30 pronounced the country's nuclear safety system "the best in the world". But the State Council review revealed more than 30 weaknesses including reduced disaster safety standards and a lack of a clear strategy for securing spent nuclear fuel and other radioactive waste at many plants.

"The strength (stability) of engineering structures of most nuclear power plants does not meet current regulatory document requirements for stresses that occur from extreme natural impacts," the report said. More...

On the day Uranus entered Aries, on March 11, Japan experienced the terrible 9.0 earthquake and the tsunami, setting off the dangerous nuclear reactors. (Uranus rules explosions and earthquakes, and was in harsh angle to Pluto, ruling plutonium and nuclear fission.) Also, later in the same month, March 2011, NATO approved the military action of the allies on Libya in a surprise attack.

More than 80 per cent of Japanese want the country's 54 nuclear reactors scrapped in the wake of this year's nuclear disaster at the Fukushima plant, a poll showed Sunday, DPA reported.

According to the poll, conducted by a nationwide opinion survey body organized by Kyodo News, 82 per cent wanted the reactors to be decommissioned either gradually or immediately, while just 14 per cent said the operations should continue, reflecting the public's mounting distrust of nuclear energy.

The country has 54 nuclear reactors including six at the Fukushima Daiichi nuclear plant. The plant was severely damaged by the March 11 earthquake and tsunami and has since leaked radioactive substances into the environment.

Of the 82 per cent, 9 per cent said the reactors should be decommissioned immediately while 19 per cent wanted scrapping to start with ones undergoing periodic inspection.

Ninety-four per cent said they were "deeply" or "to some extent" concerned about the safety of nuclear power plants after the crisis. Just 43 per cent said they had felt the same way beforehand.

Meanwhile, 84 per cent said Japan should rely more on renewable energy sources such as solar and wind, followed by 45 per cent who wanted more hydraulic power generation and 31 per cent who wanted more natural gas. Only 7 per cent said the country should depend more on nuclear power.