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My key takeaways: * In a perfect world, there would be a more ambitious program developing the breeding technology in parallel to ITER, Willms says, so that by
by westcort 4y ago
My key takeaways:
* In a perfect world, there would be a more ambitious program developing the breeding technology in parallel to ITER, Willms says, so that by the time ITER has perfected the fusion reactor there’s still a fuel source to run it
* Like many of the most prominent experimental nuclear fusion reactors, ITER relies on a steady supply of both deuterium and tritium for its experiments
* When it’s finally fully switched on in 2035, the International Thermonuclear Experimental Reactor will be the largest device of its kind ever built, and the flag-bearer for nuclear fusion
* And as ITER drags on, years behind schedule and billions over budget, our best sources of tritium to fuel it and other experimental fusion reactors are slowly disappearing
* Right now, the tritium used in fusion experiments like ITER, and the smaller JET tokamak in the UK, comes from a very specific type of nuclear fission reactor called a heavy-water moderated reactor
* “We’re hitting the peak of this tritium window roughly now.” Scientists have known about this potential stumbling block for decades, and they developed a neat way around it: a plan to use nuclear fusion reactors to “breed” tritium, so that they end up replenishing their own fuel at the same time as they burn it
* “Calculations suggest that a suitably designed breeding blanket would be capable of providing enough tritium for the power plant to be self-sufficient in fuel, with a little extra to start up new power plants,” says Stuart White, a spokesperson for the UK Atomic Energy Authority, which hosts the JET fusion project
* “It would be an absurdity to use dirty fission reactors to fuel ‘clean’ fusion reactors,” says Ernesto Mazzucato, a retired physicist who has been an outspoken critic of ITER, and nuclear fusion more generally, despite spending much of his working life studying tokamaks
* “After 2035 we have to construct a new machine that will take another 20 or 30 years for testing a crucial task like how to produce the tritium, so how are we going to block and stop global warming with fusion reactors if we will not be ready until the end of this century?” says Mazzucato
Arthur Turrell's book, The Star Builders, is an excellent overview of the state of the art of nuclear fusion technology. Unfortunately, however, fusion is unlikely to be radically cheaper than other sources.
- gitfan86 4y agoLast week Elon explained that the problem of fusion is that it will be more expensive than solar and wind.
- DennisP 4y agoThe real question is whether it's more expensive than solar/wind plus the batteries required for dispatchable power. The answer depends on the reactor design, which Elon doesn't know. There are a lot of possibilities, and if the first ones are too expensive, later ones might not be.
- gitfan86 4y agoTrue, but that is a moving target. https://ourworldindata.org/battery-price-decline https://ourworldindata.org/battery-price-decline
- ncmncm 4y agoCost for energy storage is plummeting even faster than for solar or wind ever did.
- pfdietz 4y agoAlmost certainly it will be more expensive than renewables + storage (note the importance of hydrogen there.) The cost of renewables + storage to provide "synthetic baseload" is likely less than fission. And DT fusion is likely more expensive than fission. https://model.energy/ https://model.energy/
- DennisP 4y agoYes, we discussed that pretty extensively the other week. It starts out with unrealistic assumptions for fission, including a 25-year lifespan (compared to the actual average age of US reactors of forty years) and twice the discount rate for fission as for everything else. Fix those things and nuclear does better. It also uses US fission prices, which are higher than in most of the world. On top of that, the US has unusually good geography for both wind and solar. Nuclear is much more competitive in many other countries. One ironic example is Germany, where the model suggests a 100% nuclear grid even at US nuclear costs, as long as the lifespan and discount rate are corrected.
- 4y ago
- dang 4y agoCan you please stop doing this? I'm sure these comments are well intentioned, but the pattern has become repetitive (https://hn.algolia.com/?dateRange=all&page=0&prefix=true&query=by%3Awestcort%20%22my%20key%20takeaways%22&sort=byDate&type=comment https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que...) and anything this repetitive is bad for curiosity (https://hn.algolia.com/?dateRange=all&page=0&prefix=false&sort=byDate&type=comment&query=curiosity%20repetition%20by:dang https://hn.algolia.com/?dateRange=all&page=0&prefix=false&so...). HN threads are supposed to be conversations, and conversation involves people interacting with each other.
- westcort 4y agoOkay I will not post these anymore. I might share the summarization algorithm I wrote that enables me to create these quickly, though. Thanks for helping me understand the ethos of curiosity and the diffs as the underlying principles.
- dang 4y agoYes - sharing the algorithm would indeed be interesting! Thanks for getting the point so well.