Thorium nuclear reactors – an expensive waste of time

Why are we not using Thorium instead of Uranium for power? https://in.answers.yahoo.com/question/index?qid=20150303142722AA751rC “I have followed this technology for some years with interest. It has merits and one great demerit – it is very costly – at least twice the cost of most renewables. So why go this route? The so called renaissance of uranium reactors has become a fiasco. The Finnish project with Areva was to cost $2500 per Mwe for the first prototype,with $1200 per Mwe in the following standardized units.The reality is 3 years behind schedule, 77% over budget with no hope of completion at less than a 100% overrun, and standardized successors now priced at $5000 per Mwe, four times the hoped for cost.

There is no reason whatever to claim thorium based reactors will be any cheaper. We cannot afford to waste precious time and money on nuclear, but should have a crash implementation of commercializing renewables like wind and solar thermal electric.”

Simple economics rule out thorium reactors

January 16, 2015,  Jortiz3
Contrary to popular belief, the reason light-enriched-uranium reactors are used, and not thorium or breeder reactors, is due to simple economics. To run breeder reactors and thorium reactors, the neutron density and heat density must be so great that high-temperature coolants must be used throughout the core.

The systems used to manage these coolants are as exotic as the coolants are. This leads to increased costs, on the order of 20%. This 20% is enough that utilities simply choose light-enriched-uranium so that the reactor core can be cool enough that cooling with water is possible and savings can offset the cost of mining the ridiculous quantities of natural uranium required.

 

Costs of high-temperature coolants kill the economics of thorium reactors

January 16, 2015,  Jortiz3
Contrary to popular belief, the reason light-enriched-uranium reactors are used, and not thorium or breeder reactors, is due to simple economics. To run breeder reactors and thorium reactors, the neutron density and heat density must be so great that high-temperature coolants must be used throughout the core.

The systems used to manage these coolants are as exotic as the coolants are. This leads to increased costs, on the order of 20%. This 20% is enough that utilities simply choose light-enriched-uranium so that the reactor core can be cool enough that cooling with water is possible and savings can offset the cost of mining the ridiculous quantities of natural uranium required.

High costs, weapons risk make Thorium not the superfuel they pretend it is

“The difference in the state of development of thorium versus other sources of fuel is so vast and the cost of developing the technology is so high, it’s really questionable today whether it’s worthwhile to spend a lot of money on the development of thorium.”

Is the “Superfuel” Thorium Riskier Than We Thought? 
A new study in Nature says that using thorium as a nuclear fuel has a higher risk for proliferation into weapons than scientists had believed. Popular Mechanics, By Phil McKenna December 5, 2012 
Imagine a cheap, plentiful source of energy that could provide safe, emissions-free power for hundreds of years without refueling and without any risk of nuclear proliferation. The fuel is thorium, and it has been trumpeted by proponents as a “superfuel” that eludes many of the pitfalls of today’s nuclear energy. But now, as a number of countries including China, India, and the United States explore the potential use of thorium for nuclear power, researchers say one of the biggest claims made about the fuel—its proliferation resistance—doesn’t add up.

“It may not be as resistant as touted and in some cases the risk of proliferation may be worse than other fuels,” says Stephen Ashley of the University of Cambridge. In an article published in the journal Nature online today, Ashley and his colleagues highlight the potential dangers of thorium fuel.

When thorium is irradiated, or exposed to radiation to prepare it for use as a fuel in nuclear reactions, the process forms small amounts of uranium-232. That highly radioactive isotope makes any handling of the fuel outside of a large reactor or reprocessing facility incredibly dangerous. The lethal gamma rays uranium-232 emits make any would-be bomb-maker think twice before trying to steal thorium.

But Ashley and his co-authors say a simple tweak in the thorium irradiation recipe can sidestep the radioactive isotope’s formation. If an element known as protactinium-233 is extracted from thorium early in the irradiation process, no uranium-232 will form. Instead, the separated protactinium-233 will decay into high purity uranium-233, which can be used in nuclear weapons.

“Eight kilograms of uranium-233 can be used for a nuclear weapon,” Ashley says. “The International Atomic Energy Agency views it the same as plutonium in terms of proliferation risk.”

Creating weapons-grade uranium in this way would require someone to have access to a nuclear reactor during the irradiation of thorium fuel, so it’s not likely a terrorist group would be able to carry out the conversion. The bigger threat is that a country pursuing nuclear energy and nuclear weapons (say, Iran) could make both from thorium. “This technology could have a dual civilian and military use,” Ashley says.

Laurence O’Hagan is the CEO of the Weinberg Foundation, a non-profit organization promoting the development of thorium fuel. Responding to Ashley’s Nature article, O’Hagan says proliferation concerns are overstated. “There are proliferation issues with anything nuclear,” he says. “But if you are out to make a bomb, you go after plutonium rather than thorium and uranium-233. It’s too difficult to handle.”Thierry Dujardin, deputy director for science and development of the Organisation for Economic Co-operation and Development’s Nuclear Energy Agency takes a middle of the road approach to concerns over proliferation with thorium. “It’s probably as wrong to claim there is no proliferation concern as to say it’s worse than other fuels,” Dujardin says. …….

Dujardin says, a number of advanced reactor designs, including molten salt reactors, provide similar benefits and can use existing uranium-based fuel. And for cost reasons alone, Dujardin says it may be better to continue developing next-generation reactor designs using existing uranium fuel technology.

“When a technology is in some difficulty, and nuclear technology has been shocked by the Fukushima accident in Japan, people search for a magic solution, but there is no silver bullet,” he says. “The difference in the state of development of thorium versus other sources of fuel is so vast and the cost of developing the technology is so high, it’s really questionable today whether it’s worthwhile to spend a lot of money on the development of thorium.” ………http://www.popularmechanics.com/science/energy/nuclear/is-the-superfuel-thorium-riskier-than-we-thought-14821644