Podcast in review: Omega Tau 304 “The Past, Present and Future of Fusion Energy”

I recently finished listening to episode 304 of the Omega Tau podcast (“The Past, Present and Future of Fusion Energy”).

The podcast was great. I learned a lot about fusion and the state of fusion research. But what I want to write about right now is the other stuff I took out of the podcast.

“What is your best argument against yourself?”

This is a line that the host, Markus Voelter, used on his guests. The guests throughout the entire thing were quite sanguine about the prospects of fusion power - to an extent that seemed like a bit of an overreach.

This question is excellent because it offers a way to penetrate in and see whether the responder is actually thinking fully clearly. There are very few arguments which are entirely one-sided, and there are very few clearheaded advocates who do not understand that their own position has its weaknesses. But attacking them head-on usually entrenches them and can be tedious. This question is great because it simultaneously reveals a lot about the responders’ internal state of mind and disarms them.

I’d like to try to use this technique in the future. I’d really like to remember to use it on myself - when I believe something, but I’m unclear on it, it will be helpful to ask “what’s the best argument against myself?”

By the way, the fusion researchers’ answers to this question were not especially great. They were okay. They essentially said:

• You might be pessimistic about fusion research generally because it has overpromised in the past and it has taken a long time.
• Fusion plants will still be very very expensive to construct, probably no matter what.
• Fusion power is so good that it might make energy too cheap, which encourages more aggressive cycles of consumption and resource exploitation.

None of these were presented especially well. But they can be forgiven - after all, these are fusion researchers; their livelihoods depend on this being a good idea!

Complexity can be a good thing for research avenues

This was a subtle argument put forward by the fusion researchers. It’s a completely new one to me; to them, it seemed obvious, but Markus stopped them and went over it carefully. I was glad about that because I thought it was very unusual too.

The argument goes like this: you should be optimistic about fusion research because it’s so complex and multidimensional. That complexity means we may have many “escape routes” if any one technology is a dead-end.

At first glance, this argument seems backwards. Isn’t complexity a bad thing when you’re trying to solve a problem?

Well, in this case, the complexity is that fusion power generation’s success depends on many interacting systems:

• We appear to need to get plasmas to extremely high temperatures to drive strong currents
• we need next-era materials to withstand the high-temperature plasma when it bounces out of that current field
• we need magnetic coil materials that can generate extreme fields for long stretches of time
• we need advances in theory and probably computing to understand turbulent flows for design.
• and probably many more areas too.

But success in any one of those areas might offset any difficulties in the others. Like, maybe we figure out how to control very high-temperature plasmas with very precise accuracy. Now, we don’t need as much thermally resistant shielding!

This provides (so the argument goes) some protection from any research dead-ends. This can be contrasted with the set of requirements for a space elevator:

• we need a material with enough tensile strength to pull a load all the way to orbit

That’s it. Once we have that, everything is pretty much trivial. But all our eggs are in one basket. Either the material scientists have some stroke o genius, or we are stuck. So fusion research is actually in a good place because it’s so complex.

I’m not sure I find this line of reasoning completely convincing. For one thing, it doesn’t seem obvious that success in one field will offset failures in other fields. We still might need more overall innovation than we do for a space elevator; the researchers are essentially saying “we know so little about how to do this that maybe we’ll accidentally figure it out quickly.” This sounds reassuring for their job security as fusion researchers, but I don’t think it convinces me that we’ll have fusion power generation any time soon.

Still, it’s a really oddly shaped argument, so I kind of liked it.

“There are only three solutions for our energy needs”

This was a claim made by one of the researchers. It was presented and met no resistance. They said the three are:

• Intermittent power generators (wind, solar, etc) plus batteries
• Nuclear fission
• Nuclear fusion

Is this really the complete list? This seems shockingly short! But as soon as I try to contradict them, I run into difficulty.

I think biomass might be a non-intermittent renewable source of power, but it’s really just a very inefficient (but non-intermittent!) solar setup, so maybe it’s not so convincing. I can’t imagine biomass powering most of our needs.

Distributed generation feels like it ought to fit in as an alternative in some ways, but I’m not sure. Maybe that’s really just a variation on the first solution - one which reduces battery requirements.