Thanks. So it sounds like you're saying that, unless there is some radically different plant design in the future, that there won't be an economic advantage to fusion over fission, at least in the near term.
Certainly, containing fusing plasma magnetically requires developing a much better understanding than we now have of plasma fluid dynamics under conditions of high pressure and complicated, variable magnetic field geometry, but studying plasma fluid dynamics for itself does not need multi-billion dollar equipment. Nobody wants to give plasma physicists a dime just to learn about plasma, even though it would be fantastically cheaper than what is being done instead.
The chart here shows the energy difference pretty well: https://www.nuclear-power.com/nuclear-power/fission/nuclear-...
More fuel + more energy from fuel = superior for most uses long term. If we pull it off.
Fission is already not competitive, so a technology much more expensive to build and operate is even less so. In ten years, solar and wind will be even cheaper than today, and will be supplying most of our energy needs.
(Not every place is Southern California where there are no clouds and the sun shines all year. Solar is cheap in some places, but not at high latitudes.)
Wind does not confine itself to lower latitudes.
Such reactors would also quickly destroy themselves, so would have no opportunity to pay back the investment.
The only hope for useful fusion is if work on existing designs turns out to be applicable to actually practical, aneutronic forms. Current spending on those is negligible.
Consider that the majority of startup companies with apparently good ideas never get to market. People like to think the hardest problem they know of right now is all that matters, but often it is a boring problem that sinks the company. Maybe it is technically solvable, but costs enough to destroy the value proposition.
So long as solar and wind costs are still falling fast, any prediction about the viability of competing tech is at best provisional.
Solar and wind benefit from the opposite effect: there are known problems, but they have lots of known viable solutions that are just competing for which ones (plural) will end up cheapest, or have the most side benefits, or are easiest to deploy.
It used to be that poor round-trip efficiency would sink a storage technology, but generation has become so cheap that losses matter less than other considerations. 50% loss? Build out more panels!
Hydrogen still has awful efficiency, electrolysers and fuel cells need platinum-group metals, and liquid hydrogen needs really rigorous handling, but H2 is so useful that those don't matter. Efficiency and cost will only improve. Ammonia synthesis is similar: super-useful, but maybe easier to make starting with water. (There will be a lot of waste oxygen soon.)
Iron-air batteries likewise have poor efficiency, and low discharge rate, but the material basis is very, very cheap. You can gang up thousands in parallel to get the rate you need, and stick lithium or lead cells on the front to handle load spikes. Useless for cars, fine for utilities.
Liquifying air is very mature tech, so as the basis for a storage medium it's a safe bet. Storage capacity grows with cheap tankage. And, excess LN2 is valuable, so when your tanks are full you still have revenue.
It turns out there are myriad elevated basins that would be perfect for pumped hydro storage, another very mature technology. Unlike hydro generation, you don't need a whole watershed and river valley, just hills with a dip.
Even if fusion fizzles for utilities, the mostly-aneutronic sort might be perfect for outer solar system propulsion, where a completely different set of constraints apply. And, military deployments will often not be able to lay out much solar where they land. So, even though fission is, relative to solar, super-expensive, places can be found where nothing else will do.
Fission (will?) have the advantage of being able to produce energy whenever we need it. Solar or wind need storage. And as far as I know, there are no viable storage solution as of today.
> It turns out there are myriad elevated basins that would be perfect for pumped hydro storage, another very mature technology. Unlike hydro generation, you don't need a whole watershed and river valley, just hills with a dip.
In some countries, all possible places of hydro generation have already been used. What would be the potential for new hydro solutions in Europe for example, where hydro has been exploited for decades? Again, not an expert, but I don't think that there is an obvious path in countries where population density is pretty high and without large swathe of lands, to build hydro storage to be able to produce enough energy on a sufficient long period of time. Curious to know what you think.
Using any sort of battery, based on a chemical process, will also probably have high impact on the environment. Current battery relies on rare earth material or industrial processes that are very impactful. Creating enough batteries to ensure safe power distribution for billions of people will probably be terrible for the environment.
My point is that there is no silver bullet as of now so putting all you eggs in the same basket does not seem to be a sane strategy. Investigating fusion is worth a shot I think.
And if we worry about money, there's plenty of money to go around. We are talking about the survival of civilization here. 16 billions were poured into the a company providing ways to share pictures of your baby to your high school friends ten years ago (yes Facebook). I am sure we can find the money to finance Fusion AND research on energy storage. It's a question of political will. In the end, we'll get what we deserve...
Where an elevated natural basin can be found, that can radically increase the storage capacity from hours to, potentially, weeks, and for even less expense: just the penstock needs to be built. Elevated basins are much more common than the elevated river valleys needed for pure hydro generation. A hybrid approach is to wall up one end of an elevated box canyon: a dam, technically, but inflow is pumped from below rather than drainage from above. There is some construction cost, but radically less per unit volume of storage than a complete tank. Dams with penstocks are extremely mature tech.
While fusion doesn't need containment for radioactive fuel, a reactor must be much larger than a fission plant because the volumetric energy flux density of fusing plasma is enormously lower than of uranium. And, the heat has to be collected by blasting neutrons right through the magnetic coils and into a "blanket" of thousands of tons of molten, radioactive lithium, in pipes all around, the which does need to be contained. People get testy when that much molten, radioactive lithium runs downhill.
The lithium needs to be confined in plumbing which will be weakened by the neutron blast and need to be replaced frequently, but will be deadly radioactive so need to be replaced using robots. That plumbing is really most of the reactor. Probably it should all be underground, so that when it is seen to cost more to refurbish every couple of years than it is worth, it is already buried.
Meanwhile, the lithium needs to be processed continuously to extract transmuted tritium to use for fuel. It is hard to imagine molten lithium processing being as cheap as managing the water and steam in a fission reactor.
Then, you need to move the heat from the lithium into liquid that will not pick up its radioactivity, thence to water for steam for the turbines. And, you need to maintain the steam turbines frequently, same as in a fission reactor.
Contrast this to negligible upkeep cost for solar and wind, which mostly amounts to unbolting and replacing them as they pass two decades of service. Your storage method might need some upkeep, but you chose it for its low cost.