[ When trucks stop running, civilization as we know it ends. Nuclear electricity doesn’t matter a rat’s ass if trucks can’t be electrified to run on batteries or overhead wires — especially the tractors and harvesters that plant and harvest billions of acres of farmland. Even if trucks can be electrified, it won’t matter if thorium or uranium nuclear power plants can’t be flexibly ramped up and down to match the ever-increasing amounts of renewable power mainly generated by wind and solar as fossil fuels decline. Nuclear (and coal) plants now typically take 6 to 8 hours to ramp up or down, but wind and solar require a response within seconds as they abruptly stop and start, which is now done with natural gas, a finite resource that is fast disappearing despite all the hoopla about 100 to 200 years of energy independence. And finally, money would be better spent on determining whether the energy returned on invested is at least 8 or more (Lambert, Hall 2011), to mine, process, build, and maintain thorium power plants before we start building them. Alice Friedemann www.energyskeptic.com ]
Bagla, P. November 13, 2015. Thorium seen as nuclear’s new frontier. Science 350: 726-727.
In the 1950s, U.S. nuclear scientists proposed building a fleet of nuclear-powered airplanes. That was probably a bad idea.
Compared with uranium, thorium is 3 to 4 times more abundant than uranium and harder to divert to weapons production, and it yields less radioactive waste. But thorium can’t simply be swapped in for uranium in standard reactors. Driving the interest in thorium is the latest in a string of accidents involving uranium-fueled power reactors. The meltdowns at the Fukushima Daiichi Nuclear Power Plant in Japan in March 2011 prompted many countries to take operating reactors offline and to scale back or scuttle plans to build new ones. India plans to have a thorium power reactor running within 10 years.
Thorium holds little appeal for bomb makers: Daughter isotopes, born as thorium naturally decays, are highly radioactive, emitting gamma rays that would fry weapon electronics and make thorium-derived bombs cumbersome to store. At the same time, thorium-based fuels yield much less high-level radioactive waste than uranium or plutonium, and molten-salt reactors are touted by their backers as meltdown proof.
The catch is that thorium itself is not fissile…. it is like wood too soggy for a fire and must be converted into fissile material by bombarding thorium with neutrons to transmute it into fissile uranium-233. The disaster-scarred track record of uranium reactors casts a long shadow on thorium, too. Ever since the United States during the Cold War went whole hog into uranium, “the world has been paying a price for the wrong technology choice,” argues Jean-Pierre Revol, president of the international Thorium Energy Committee in Geneva, Switzerland.