Comment by BizarroLand | Hacker News Reader

Comment by BizarroLand | Hacker News Reader

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Real talk, the point is not that whatever system is first past the post for fusion becomes the gold standard and fills the planet.

The issue right now is cracking the code. Once that is done, performance gains and miniaturization can take place.

Fusion can work on lots of things. Its possible that a fusion system the size of a car could be made within 25 years of the code being cracked that would power a house, or the size of a small building that could power a city block.

The waste product of hydrogen fusion is helium, a valuable resource that will always be in high demand, and it will not be radioactive.

And yes, it will need coolant as with hot fusion the system uses the heat to turn a turbine, but that coolant isn't fancy, it's just water.

Fusion has the potential to solve more problems than it causes by every metric as long as it is doable without extremely limited source materials, and this is what these big expensive reactors are trying to solve.

You’ve disputed nothing I’ve said and unless a dramatically higher temperature fusion reaction that does not generate a neutron flux is achieved, it will generate radioactive waste as a matter of factual physics. Thank you though!

I mean, yes, you're right, but it's not a permanently radioactive waste.

Quote:

A fusion power plant produces radioactive waste because the high-energy neutrons produced by fusion activate the walls of the plasma vessel. The intensity and duration of this activation depend on the material impinged on by the neutrons.

The walls of the plasma vessel must be temporarily stored after the end of operation. This waste quantity is initially larger than that from nuclear fission plants. However, these are mainly low- and medium-level radioactive materials that pose a much lower risk to the environment and human health than high-level radioactive materials from fission power plants. The radiation from this fusion waste decreases significantly faster than that of high-level radioactive waste from fission power plants. Scientists are researching materials for wall components that allow for further reduction of activation. They are also developing recycling technologies through which all activated components of a fusion reactor can be released after some time or reused in new power plants. Currently, it can be assumed that recycling by remote handling could be started as early as one year after switching off a fusion power plant. Unlike nuclear fission reactors, the long term storage should not be required.

https://www.ipp.mpg.de/2769068/faq9

Basically, whatever containment vessel becomes standard for the whole fusion industry would need probably an annual cycle of vessel replacements, which would be recycled indefinitely and possibly mined for other useful radioactive byproducts in the process.

The amount of radioactive scrap produced by hypothetical decommissioned radioactive fusion containment vessels is laughably trivial compared to fission waste streams. Even accounting for the most pessimistic irradiation models of first-wall materials, the total radioactive burden remains orders of magnitude below legacy technologies. The half-lives of such activated components like predominantly steel alloys and ceramic composites trend dramatically shorter than actinide-laden spent fuel, with activity levels plummeting to background within mere decades rather than geological timescales. This makes waste management a single-generation engineering challenge rather than a multi-millennial obligation

The long term activity of the waste is certainly lower, but the volume of the waste is likely much higher. And much of the cost is driven by volume, not activity.

As a species, we're spectacularly bad at negative externalities.

We are also very bad at anything very long term. We've hardly pulled off any physical project to last more than one generation recently. We barely invest in any.

The winning energy tech of the future better have as little negative externalities as possible, especially long term ones.

Hey, there it is! Lots of radioactive waste being generated on a continuous business but maybe baby with dreams and creams we can decommission it with robots and recycle it all. Meanwhile a reactor is offline for refurbishment for days, weeks, months, blowing a hole in the economics of it all.

Unironically: you’re the first person I’ve come across to openly acknowledge this issue. Thank you.

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