[jandrese]

At this point I would bet against commercial fusion power plants. It was always questionable if they would be cost competitive with fission power plants, but now even those are being replaced by renewables and grid storage.

The bigger problem is that fusion plants aren't useful for making weapons. Fission plants were basically a side project of the nuclear arms race, which is why they're a dying industry now. The world already has all of the nuclear bombs it will ever need and despite all of the promises they never managed to compete on cost. It's so much easier and cheaper to install wind turbines, solar panels, and grid scale batteries that there will probably never be a market for a commercial fusion power plant.

[s1artibartfast]

Strong Wind doesn't exist on asteroids and many planets, so I think there will be a long term need. Solar power decreases with the cube root of distance from the sun,so twice the distance is 1/8th the flux

[TobTobXX]

Nitpick: Radiation decreases with the square of the distance (twice the distance, 1/4 the energy). This is because the surface of a sphere (which is where energy is collected) is 2D, not 3D.

[s1artibartfast]

I stand corrected

[jandrese]

I'm not concerned about commercially viable space colonies in my lifetime.

The real reason for fusion was that fission is not a renewable resource. In a few thousand years there will be a fuel problem with fission and we would be forced to switch to fusion if we had a fully nuclear power system.

[BobaFloutist]

I'm entirely content on relying on sci-fi energy production for a few thousand years from now.

This might sound like the same attitude that put us in our present climate crisis, but that was on the order of decades to centuries. Thousands of years include such unbelievable potential of technological development that there seems no point in trying to predict the actual challenges we'll face.

[surfaceofthesun]

Interestingly enough, some of the advancements in fusion research and lasers may help with fission waste fuel recycling. [1] Though breeder reactors might end up being more economical.

https://nap.nationalacademies.org/read/4912/chapter/20

[s1artibartfast]

Who said anything about concern? Im not in charge of making global decisions about fusion research, and I doubt you are either.

That leaves low stakes idle speculation.

[pfdietz]

We'll let the space colonists worry about that. It provides no justification for anyone I know to pay for it.

Solar decreases as 1/r^2. Cube root? Where did that come from?

[deburo]

There's a huge surge of investment into Nuclear these last few years. Innovation is starting again in that sector, I wouldn't bet against it.

[pfdietz]

Investment in renewables dwarfs that in nuclear now. Hell, it's exceeding investment in fossil fuels.

[notTooFarGone]

So replacing old infrastructure is now an investment? There are just many reactors EoL and I'd say replacing those is not a sign that nuclear is booming right now.

The future is wind/solar/battery on cost alone.

[pfdietz]

> So replacing old infrastructure is now an investment?

Yes? What did you think it was, chopped liver?