fantastic PBS Space Time on what the last steps are going to be to finally make fusion possible

https://www.youtube.com/watch?v=nAJN1CrJsVE

(fusion is -always- just a decade away, perpetually, lol)

dale_glass an hour ago | parent | next [-]

It's a nice video, but a striking thing about it is that it ends with "I just want my infinite free energy". Where on earth is that supposed to come from?

Fusion is ultimately a fancy way to boil water. The tokamak (or stellarator) heats a given amount of water per second, which after losses to power the plant itself and the losses in the steam turbine, makes some finite amount of MWh to output to the grid. This contraption is as the video says very non-trivial to design and build and so it costs some very non-zero amount of money, and lasts a finite time (walls are damaged)

Big $$$ / finite_amount_of_mwh / life_expectancy = min_cost_per_mwh, if we want to pay this thing off. Very possibly more than existing methods.

I'm extremely on the side of doing scientific research, but I'm baffled by constantly bumping into people who suggest somehow fusion is going to mean infinite free power, or anything even close to that.

So far the tech seems headed towards just being an alternate form of a fission plant -- complex, expensive, slow to build, possibly won't ever make a profit. Likely worse, since fission is a known, mature tech.

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JumpCrisscross 5 hours ago | parent | prev [-]

> fusion is -always- just a decade away, perpetually

Wasn't it perpetually 20 to 50 years away? I'm not an expert on the space. But new computational methods and magnets seem to be genuine steps forward.

	▲	rcxdude 2 hours ago \| parent \| next [-]
		IIRC the one of the first times a group put timelines to a fusion reactor they had time vs funding level of something like 20 years/50 years/never, and the funding level that actually materialised was below the 'never' amount and yet it started the 'always 20 years away' joke. Now I think the timeline was probably still optimistic but fusion is also obviously a very expensive thing to develop and while it's gotten a lot of funding it's still at the 'in the background' level.
	▲	ck2 4 hours ago \| parent \| prev [-]
		the PBS Space Time episode suggests to me the housing walls might be the biggest problem it consumes itself or makes molecules that are destructive to the walls or insanely toxic so can never risk leaks whatever solution they come up with I suspect it will require a lot of constant maintenance on the first generation