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 turn out to be too costly.
Photo voltaic and wind are a joke, and sensible fusion is many a long time away. Sadly, so few folks perceive the physics, {that a} multitude of mis-conceptions cloud this subject, and few even obtained 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 may 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 gas. However so-called quick breeder reactors may faucet into this huge provide of fertile isotopes, and breed and burn 100% of the gas. 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 good a brand new technology of sensible secure breeder reactors. By far essentially the most promising expertise is the Molten Salt Reactor, the place the reactor gas is a liquid that circulates from the ‘core’ by means of warmth exchangers, to provide steam like every reactor. It runs at atmospheric stress so it can’t endure steam explosions, and if If something goes fallacious, the gas may be emptied from the reactor by gravity, shutting it down in seconds.
Curiously, the person who developed our current reactors, Alvin Weinberg, instantly noticed how unsafe they have been. So within the 1950’s started growing the Molten Salt reactor. He constructed a number of which labored flawlessly. However the authorities shut his undertaking down within the 1970’s. Now could be the time to resurrect his sensible design, and construct a technology 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 resembling uranium-233. The ultimate stage employs the Superior Heavy Water Reactor (AHWR) and different thorium-based fuels which are designed to function on thorium-plutonium and thorium-uranium-233 blended oxide fuels. Thorium will not be gas, as one reader identified, however can turn out to be fertile when was uranium-233.
Most present nuclear reactors are gentle water reactors (LWRs) that use enriched uranium (usually about 3–5% U-235) as gas. These reactors extract lower than 1% of the power out there in pure uranium, as they primarily fission U-235 and go away the far 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 gas 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 improve gas 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 also can considerably cut back the amount 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 National Laboratory within the Fifties and Nineteen Sixties. The Molten Salt Reactor Experiment (MSRE) operated efficiently however was discontinued within the Seventies because of shifting priorities and funding.
Alvin Weinberg believed that light-water reactors (LWRs) have 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 complicated nature added to the danger 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 stress, decreasing threat.
Former President John F. Kennedy believed that succeeding in producing a possible molten salt reactor was “very distant” after the US Air Drive spent $1 billion ($7 billion as we speak) from 1946 to 1961 on the Plane Nuclear Propulsion program. The US authorities could have deserted plans to study molten salt nuclear reactors, however the Canadian, Indonesian, and Chinese language governments have invested tens of hundreds of thousands into growing the expertise. None apart 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 undertaking. 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 method to changing into the world’s main nuclear tremendous energy—China IS the world’s main nuclear tremendous energy.
