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The Bizarre Reactor Scientists Hope Will Save Fusion Research (sciencemag.org)
sciencehabit writes: In a gleaming research lab in Germany's northeastern corner, researchers are preparing to switch on a fusion device called a stellarator, the largest ever built. The €1-billion machine, known as Wendelstein 7-X looks a bit like Han Solo's Millennium Falcon, towed in for repairs after a run-in with the Imperial fleet. Stellarators have long been dark horses in fusion energy research but the Dali-esque devices have many attributes that could make them much better prospects for a commercial fusion power plant than the more popular tokamaks: Once started, stellarators naturally purr along in a steady state and they are not prone to the potentially metal-bending magnetic disruptions that plague tokamaks. Unfortunately they are devilishly hard to build.
Title doesn't mention "new", neither does summary.
The summary also correctly implies stellarators are in fact old. Stellarators have long been dark horses
The bullet points where you give numbers make no sense. 10000 tons of lithium? Design studies for DEMO, which would have several GW of thermal output, have a blanket volume on the order of 500 m^3. Even if assuming that was all lithium, you are talking about 300-400 tons, much smaller than 10000 tons. 10000 tons would be a block of lithium about 27 m on a side, which is much larger than the whole reactor vessel design.
Scaling the costs is very difficult to do. A production reactor would be far cheaper in many ways, because you don't need as much diagnostic access. A lot of compromises have to be made to just get enough space between the magnets of many designs for diagnostics, plus the costs of diagnostics (millions of dollars each for the many of them), plus the costs to use, maintain and analyse them. This is part of why designs for DEMO are only about 15% larger than ITER, but of a much more compact design considering it is producing nearly 4-8 times as much thermal output.
Disasters and waste disposal issues for fission are only a concern if we keep doing it like we've done for the last 40 years. We've seen liquid fuel fission that promises to not only be "disaster" proof but can also "eat" the radioactive waste from the reactors we've used for decades.
Liquid fuel fission reactors like liquid fluoride thorium reactors (LFTRs) can be made to be walkaway safe, where any damage would be limited to the destruction of the reactor. LFTRs have safety mechanisms that prevent the possibility of "China Syndrome" style meltdowns. This is primarily because the fuel is already melted, loss of containment means removal of the mechanisms that maintain fission. If the reactor runs too hot a normal "scram" operation involves dumping the core fuel into a drain tank that removes the fuel from the core, the tank is designed in such a way that just air cooling prevents further damage. Thermal failure of the core, as in it gets so hot that it melts, mean the fuel spills onto the floor of the reactor building, and then flows into that same drain tank. It is impossible for a LFTR failure to result in a massive release of radiation.
Once the powers that be in the federal government realize the value of LFTR we will see fission not only get cheaper but also prove that fission does not mean we have to pile up radioactive waste. That "waste" we have now exists only because of federal government policies that prevent the reprocessing of spent fuel into new fuel and valuable industrial material. LFTR could prove to be a means for making reprocessing of "spent" fuel that is both economically and politically feasible. Much of what makes up "spent" fuel from current reactors is unburnt uranium, stuff that is no more radioactive than what was dug from the ground. If we can get that uranium out and turn it into something useful then not only have we just solve 90% of the "waste" problem but we've also solved an energy problem.
There's two ways to dispose of radioactive waste. One way is to store it away until it decays, which can take hundreds of years. (Anything that takes longer than hundreds of years to decay is "radioactive" only in the theoretical sense, it's not a hazard to life.) Another way to dispose of radioactive material is in a reactor. If we do it right then that reactor can not only destroy radioactive material but we also get valuable energy from it.
Like you say, if you ask someone from the 1970s about nuclear power they'll tell you about The China Syndrome. The reason we still think of fission power like we do in the 1970s is because not much has changed in fission technology since then. Why haven't we seen anything new in fission technology since the 1970s? Likely because we have the same people in the Department of Energy that we did in 1979. Time will prove that nuclear fission is safe, cheap, reliable, and the only option we have. That time may come, sadly, only because the people that are holding the technology back have died of old age.
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