For a piece of engineering we have to keep in mind what is the most promising, and yet safe and affordable? This concern has nuked nuclear reactors over the years. For those light water reactors that were built over the 60 years, most are still operating and "reasonably safe," so far. To expand the abundance of electricity that our species needs to survive, we have to work within the constraints of engineering. For the best efficiency and costs we need to use advanced solar cells to power up advanced batteries, to be used for all residences, on a 7 x 24 basis. Anything less, is just environmentalists having their say over the rest of us. There have been big advances in solar cells and batteries lately, and this is the cheapest and easiest way to go. One is the perfected perovskite solar cell, created by many of the leading British universities all on their own. Before this, any perovskite based device would crumble to dust upon exposure to air. https://www2.physics.ox.ac.uk/research/semiconductor-materials-devices-nanostructures/photovoltaics Or this-https://energynow.com/2020/07/technology-breakthrough-could-increase-ev-range-battery-life/ For safer nuclear fission operation (uranium 235) Nuscale's mini light water reactor uses this innovation, from Lightbridge, originally developed by Purdue school of Engr.https://www.ltbridge.com/lightbridge-fuel Advantage? Safer because its much harder to melt down. It doesn't hold the heat like the 1940's assemblies cobbled together by Enrico Fermi. Or even better, these Triso fuel modules seem inherently safer, yet this concept is for a gas reactor, and I fear that the coolant gas is helium (short supply) rather than say, CO2, or Nitrogen? https://www.wired.com/story/nuclear-power-balls-triso-fuel/
-----Original Message-----From: John Clark <[email protected]> To: [email protected] Sent: Fri, Jul 24, 2020 11:13 am Subject: Re: Planet of the Humans, produced by Michael Moore On Fri, Jul 24, 2020 at 2:51 AM Alan Grayson <[email protected]> wrote: > https://planetofthehumans.com/Largely correct, but omits the solution; > thorium reactors. Check Wiki for the residuals; no gamma rays. AG YES! I've been a fan of Thorium reactors for years, in particular Liquid Fluoride Thorium Reactors (LFTR) and I'm very impressed, I don't believe nearly enough is being done in this area. Consider the advantages: *Thorium is much more common than Uranium, almost twice as common as Tin in fact. And Thorium is easier to extract from its ore than Uranium. *A Thorium reactor burns up all the Thorium in it so at current usage that element could supply our energy needs for many thousands, perhaps millions of years; A conventional light water reactor only burns .7% of the Uranium in it. * To burn the remaining 99.3% of Uranium you'd have to use a exotic fast neutron breeder reactor, Thorium reactors use slow neutrons and so are inherently more stable because you have much more time to react if something goes wrong. Also breeders produce massive amounts of Plutonium which is a bad thing if you're worried about people making bombs. *Thorium reactors produce an insignificant amount of Plutonium, they do produce Uranium-233 and theoretically you could make a bomb out of that, but it would be contaminated with Uranium-232 which is a powerful gamma ray emitter which would make it suicidal to work with unless extraordinary precautions were taken, and even then the unexploded bomb would be so radioactive it would give away its location if you tried to hide it, and the gamma rays would destroy its electronic firing circuits, and degrade its chemical explosives. As far as I know a U-233 bomb was attempted only twice, in 1955 the USA set off a Plutonium/U233 composite bomb, it was expected to produce 33 kilotons but only managed 22; the only pure U-233 bomb I know of was set off in 1998 by India, but it was a fizzle, a complete flop, it produced a minuscule explosion of only equivalent to 200 tons of TNT due to pre-detonation. For these reasons even after 75 years no nation currently has U233 bombs in their arsenal because if you want to kill people on a mass scale Uranium-235 and Plutonium-239 are far more practical than Uranium-233. *A Thorium reactor only produces about 1% as much radioactive waste as a conventional reactor, and the stuff it does make is not as nasty, after about 5 years 87% of it would be safe and the remaining 13% in 300 years; a conventional reactor would take 100,000 years. *A LFTR Thorium reactor has an inherent safety feature, the fuel is in liquid form (Thorium dissolved in un-corrosive molten Fluoride salts) so if for whatever reason things get too hot the liquid expands and so the fuel gets less dense and the reaction slows down. *There is yet another fail safe device. At the bottom of the reactor is something called a "freeze plug", fans blow on it to freeze it solid, if things get too hot the plug melts and the liquid drains out into a holding tank and the reaction stops; also, if all electronic controls die due to a loss of electrical power the fans will stop the plug will melt and the reaction will stop. *Thorium reactors work at much higher temperatures than conventional reactors so you have better energy efficiency; in fact they are so hot the waste heat could be used to desalinate sea water or generate hydrogen fuel from water. * Although the liquid Fluoride salt is very hot it is not under pressure so that makes the plumbing of the thing much easier, and even if you did get a leak it would not be the utter disaster it would be in a conventional reactor; that's also why the containment building in common light water reactors need to be so much larger than the reactor itself and why the walls of it needs to be so thick. With Thorium nothing is under pressure and there is no danger of a disastrous phase change, like ultra hot pressurized water turning into steam, so the super expensive containment building can be made much more compact. John K Clark-- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/CAJPayv0nR-TNwxkhXka650WSY0oXmasQarqNbzEGE-g2BfHJ2Q%40mail.gmail.com. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/602856683.6270451.1595807901346%40mail.yahoo.com.

