What do you think of Thorium LFTR Nuclear Reactors?

[lernerconsulting]

7. Simple differences LWR vs LFTR

The Huffington Post article is unclear, mixing facts and hype, mixing facts about Light Water Reactors (LWR, most reactors in the world) and Liquid Fluoride Thorium Reactors (LFTR) and solid fueled thorium reactors. People commenting on that article think because they know "nuclear reactors" or heard some about solid-fueled thorium reactors they understand about liquid-fueled thorium reactors. Surely you can understand they are very different technologies, right? (Some writers there are deliberately confusing things, the LWR industry makes a lot of money making nuclear waste and storing nuclear waste).

Almost all safety issues with LWR are from using water as the coolant. High pressure is needed to keep water from boiling away, needing complex engineered systems and huge containment buildings. Steam is what would carry radioactivity into the atmosphere; high pressure or hydrogen from water are what can explode.

LWR has nuclear waste problems, from using solid fuel. Less than 2% of the fuel can be used, since the fission byproducts (think of it like the "exhaust in your car&quot are trapped in the fuel rod, stopping the nuclear reaction.

The Atomic Energy Commission report to the President and Congress recommended switching to other types of nuclear reactors, for better safety and less nuclear waste. 50 years later we still have not. Most people now think "nuclear reactor" means LWR. Maybe it's time to reconsider whether LWR is a reactor to continue using, and maybe LFTR, or another molten salt reactor, makes more sense?

LWR is a "solid fueled, water cooled uranium reactor". Some countries (especially India) are attempting a "solid fueled, water cooled thorium-to-uranium reactor"; it will run much like a LWR (since it is solid fueled, water cooled).

LFTR is a specific type of "molten fueled, salt cooled, thorium-to-uranium reactor". With molten fuel, the fission byproduct "exhaust" can be easily removed and properly stored; the fuel can therefore be thoroughly used. With salt coolant, there are no "loss of coolant accidents possible", since the salt won't evaporate; there are no high pressure explosions possible, since there is no high pressure; there can't be hydrogen explosions, since there is no hydrogen present.

People calling a reactor "a thorium reactor" or "a uranium reactor" are misunderstanding. It isn't "yea thorium we won't use uranium". Thorium converts to uranium inside the reactor. The type of uranium produced from thorium (U233) makes less waste than the type of uranium used in LWR (U235, rare, 0.7% of natural uranium) or the uranium-converted-to-plutonium used in other reactors. Plus thorium is almost 4 times as abundant as uranium, and it doesn't need to be enriched (U235 needs to be more concentrated to be useful; all thorium can be used).

To produce 1 gigawatt electricity for a year, in a LFTR, takes 800kg of thorium or uranium/plutonium waste. 83% of the fission byproducts are safe in 10 years, 17% (135 kg, 300 lbs) within 350 years, no uranium or plutonium left as waste. After that, radiation is below background radiation levels. (Compare to 250,000kg uranium to make 35,000kg enriched uranium for a LWR, all needing storage for 100,000+ years. The fission byproducts for LWR are comparable, ~ 800kg, but trapped in the fuel rods with all that unused uranium.)

Instead of Storing uranium, LFTR uses it as fuel, like a nuclear reactor should.
Instead of having to keep water from evaporating, LFTR uses a coolant that won't evaporate.
Instead of avoiding nuclear meltdown, LFTR is designed to use molten fuel.
Instead of trapping fission byproducts in the fuel, LFTR separates and stores them until they are safe and valuable chemicals.

For much more detail, clearly presented, how it works, how it can be so much safer, what is needed to build it, how it should survive natural disasters or accidents or terrorists, see What is a LFTR and How Can a Reactor Be So Safe?