CarwilBJ's Twitter Archive—№ 33,400

A quick run-down of the #NuclearFusion timeline and cost issues. TL;DR: Best-case nuclear fusion is too late to help w/ climate change; might never get cheaper than renewables.
Permalink On twitter.com ♻️ 2 Retweets ❤️ 1 Favorite 2022 Dec 13 Mood +2 🙂

…in reply to @CarwilBJ
Nuclear fusion plans involve the a multi-step process: ignition; test reactor; demonstration reactor; commercial reactor. The ITER test reactor is under construction. Should run plasma by 2025, could fuse tritium and deuterium by 2035. en.wikipedia.org/wiki/ITER
Permalink On twitter.com 2022 Dec 13 Mood -1 🙁

…in reply to @CarwilBJ
Facilities like the NIF, which just demonstrated break-even energy use within the chamber and ITER, which would operate at a larger scale, do not have a system or plan for absorbing that energy and making electricity. That's the role of a DEMO-class demonstration reactors.
Permalink On twitter.com 2022 Dec 13 Mood +1 🙂

…in reply to @CarwilBJ
Unlike a fission reactor*, fusion reactors release much of their energy in the form of high-energy neutrons. To use this energy, highly durable and expensive materials must surround the reactor and heat up, ideally transferring that energy. iaea.org/newscenter/news/neutrons-blast-fusion-materials-in-new-iaea-project
Permalink On twitter.com 2022 Dec 13 Mood +2 🙂

…in reply to @CarwilBJ
Constant irradiation means that these materials will wear out before a hypothetical fusion reactor does itself. This is why replaceable components cost is many times greater than the cost of tritium/deuterium fuel. (assuming functional material exist) sciencedirect.com/science/article/pii/S0360544218305395
Permalink On twitter.com 2022 Dec 13 Mood +3 🙂

…in reply to @CarwilBJ
All of this requires a test run at the demonstration power plant level. Under the current timeline, these plants might come online in 2051. en.wikipedia.org/wiki/DEMOnstration_Power_Plant
Permalink On twitter.com 2022 Dec 13 Mood -1 🙁

…in reply to @CarwilBJ
Fusion-boosting research articles like this one then assume that there will be an inherent cost reduction as multiple plants are built. The tenth plant will cost 40% less than DEMO, because technology is always getting cheaper, right? sciencedirect.com/science/article/pii/S0360544218305395
Permalink On twitter.com 2022 Dec 13 Mood +2 🙂

…in reply to @CarwilBJ
Under these scenarios we get a price tag of $8.5B for a 950MW DEMO2 power plant, in 2015 dollars. So basically, at the high-end of nuclear fission prices.
Permalink On twitter.com 2022 Dec 13 Mood 0

…in reply to @CarwilBJ
In 2018, the article writers found a levelized cost of energy for fusion of $117 / MWh. Using mid-2010s costs of renewables, it was then competitive with wind and solar. But not any more…
On twitter.com 2022 Dec 13 Mood +2 🙂

…in reply to @CarwilBJ
Renewable technologies are benefiting NOW from increases in know-how and the fact that there are many other industries that use silicon, magnets, and motors. Their LCOE has plunged in the past decade.
Permalink On twitter.com 2022 Dec 13 Mood 0

…in reply to @CarwilBJ
So under aggressively optimistic scenarios fusion energy in 2060 could cost $94/MWh (the $75 minimum cost, subjected to inflation), more than any renewable source costs in 2022. Fusion power could simply be an uncompetitively expensive way to make electricity.
Permalink On twitter.com 2022 Dec 13 Mood +2 🙂

…in reply to @CarwilBJ
All climate mitigation scenarios require full replacement of fossil-fuel electricity generation before 2050. Nuclear fusion power would come afterwards, too late to matter for climate.
Permalink On twitter.com 2022 Dec 13 Mood +1 🙂

…in reply to @CarwilBJ
If, as I'm arguing here, nuclear fusion will never be cost competitive with renewables, its only comparative advantage is its density of power production. Perhaps there are high-energy applications (space elevators?, particle accelerators?) that would benefit from such a source.
Permalink On twitter.com 2022 Dec 13 Mood +6 🙂