COMMENT: Martin,
Very long time reader and fan. I’m a physicist, I’ve spent years proving mathematically what you say about local weather change.
It’s apparent that humanity should embrace nuclear fission to interchange fossil fuels as they slowly deplete and develop into too costly.
Photo voltaic and wind are a joke, and sensible fusion is many many years away. Sadly, so few folks perceive the physics, {that a} multitude of mis-conceptions cloud this matter, and few even acquired into your submit.
First, Thorium produces roughly the identical energy pound for pound as Uranium or Plutonium. However Thorium IS NOT FUEL, like Uranium 238 it’s FERTILE however not FISSILE: it can’t ‘burn’ by itself. Nevertheless, Thorium 232 will be bred into the fissile isotope Uranium 233, which burns similar to Uranium 235. This breeding course of already occurs to Uranium 238 in our current reactors. It absorbs a neutron, and decays into Plutonium 239, which burns even higher than Uranium 235.
All our present reactors depend on enriched Uranium to function, which suggests they burn solely 4% of their gasoline. However so-called quick breeder reactors may faucet into this huge provide of fertile isotopes, and breed and burn 100% of the gasoline. Simply burning it up fully additionally makes the waste vastly much less harmful.
The physics of breeder reactors is well-understood, however we’d like engineering analysis to excellent a brand new era of sensible protected breeder reactors. By far essentially the most promising know-how is the Molten Salt Reactor, the place the reactor gasoline is a liquid that circulates from the ‘core’ by way of warmth exchangers, to provide steam like all reactor. It runs at atmospheric strain so it can’t undergo steam explosions, and if If something goes flawed, the gasoline will be emptied from the reactor by gravity, shutting it down in seconds.
Apparently, the person who developed our current reactors, Alvin Weinberg, instantly noticed how unsafe they had been. So within the 1950’s started creating the Molten Salt reactor. He constructed a number of which labored flawlessly. However the authorities shut his challenge down within the 1970’s. Now could be the time to resurrect his good design, and construct a era of a lot safer, much less cheap and extra environment friendly fission reactors to energy humanity’s future.
REPLY:
Pressurized Heavy Water Reactors (PHWRs) fueled by uranium generate plutonium. That plutonium is then utilized by Deploy Quick Breeder Reactors (FBRs) to create fissile materials akin to uranium-233. The ultimate stage employs the Superior Heavy Water Reactor (AHWR) and different thorium-based fuels which might be designed to function on thorium-plutonium and thorium-uranium-233 blended oxide fuels. Thorium will not be gasoline, as one reader identified, however can develop into fertile when changed into uranium-233.
Most present nuclear reactors are mild water reactors (LWRs) that use enriched uranium (usually about 3–5% U-235) as gasoline. These reactors extract lower than 1% of the power accessible in pure uranium, as they primarily fission U-235 and go away the way more plentiful U-238 largely unused. The declare that they burn solely 4% is broadly correct, however the true quantity is a bit nearer to 1% for once-through cycles, and as much as 4-5% for sure fashionable gasoline cycles.
Quick breeder reactors (FBRs) are designed to transform fertile isotopes (like U-238 or Th-232) into fissile isotopes (like Pu-239 or U-233), enabling them to extract almost all of the potential power from uranium or thorium. This will theoretically enhance gasoline utilization by an element of 100 in comparison with LWRs. In apply, FBRs can make the most of 60–70% of uranium’s potential power, with the rest being fission merchandise and a few unconverted fertile materials. Breeder reactors may also considerably cut back the quantity and long-term radiotoxicity of nuclear waste, as most actinides are consumed, leaving primarily shorter-lived fission merchandise.
Alvin Weinberg led the event of the pressurized water reactor (PWR) and pioneered molten salt reactor analysis at Oak Ridge Nationwide Laboratory within the Nineteen Fifties and Sixties. The Molten Salt Reactor Experiment (MSRE) operated efficiently however was discontinued within the Nineteen Seventies on account of shifting priorities and funding.
Alvin Weinberg believed that light-water reactors (LWRs) had been extraordinarily dangerous and recognized points with loss-of-coolant accidents (LOCA), core meltdowns, and containment breaches, in addition to insufficient scaling of containment buildings. The advanced nature added to the chance of human error. “Can we develop nuclear reactors whose security is deterministic, not probabilistic, and which, if developed, would meet the general public’s craving for assurance of security, not merely assurance of the chance of security?” he requested. His proposed reactor makes use of liquid sodium versus water as coolant, permitting the reactor to function at a decrease strain, decreasing danger.
Former President John F. Kennedy believed that succeeding in producing a possible molten salt reactor was “very distant” after the US Air Power spent $1 billion ($7 billion at this time) from 1946 to 1961 on the Plane Nuclear Propulsion program. The US authorities might have deserted plans to examine molten salt nuclear reactors, however the Canadian, Indonesian, and Chinese language governments have invested tens of hundreds of thousands into creating the know-how. None aside from Invoice Gates funded the nuclear enterprise Terrapower that has produced a molten chloride quick reactor, tying this into his local weather change marketing campaign.
China created the primary totally operational thorium molten salt reactor in 2024 and stays the one nation to have efficiently accomplished the challenge. This yr, the Chinese language authorities produced a live-refueled reactor and plans to assemble a bigger 10 MW model by 2030. China introduced its thorium discovery one month after scientists introduced their groundbreaking achievement.
So I stand corrected—China will not be on its strategy to changing into the world’s main nuclear tremendous energy—China IS the world’s main nuclear tremendous energy.
