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)
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)
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.
I had the same thought recently, that if a new power source was created that was like, a perpetual superheated cube or something with no input costs, it still might actually be beaten by solar + batteries. If not right now, then in just a few years.
Since you'd still end up having to build a gigantic heat exchange setup with steam turbines, pipes/ducts/pumps, generators, valves, gauges, vents, maybe even a cooling tower, etc. Plus a labyrinth of catwalks, ladders, access tunnels for workers in hard hats servicing/inspecting/replacing stuff who are on-site 24/7 and exposed to non-trivial occupational hazards dealing with superheated liquids at high pressure every day.
The entire concept of a steam turbine is just fundamentally a big hassle compared to an inexpensive solid state slab + batteries that are modular and basically plug-and-play by comparison.
> 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.
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.
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
Then they are wrong. The biggest problem is efficiently gathering energy from the fusion reaction. Right now, we can only get a tiny fraction (less than 1%) of the energy out. If that can't be raised to 50% or so, fusion will never happen.