I feel like little fusion has kind of missed the boat. It's been "just a few decades away" since I was in school, and that's a good while ago now.
We can already get limitless clean energy from the real sun.
this post was submitted on 21 Jan 2025
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0 theoretical hope for fusion energy to ever provide electricity under 30c/kwh. These are hot plasma experiments, which could be used to produce mass HHO from water vapour at just 2200C-3000C, even if endothermic. Can get energy from concentrated solar mirrors or just PV solar if plasma is used. Cooling magnets is a huge energy drain. HHO provide the highest turbine energy gain, though a net gain pathway is just slightly more in reach than fusion.
Meanwhile in America
Meh, net gain is the point, long cycles well be useful for production. Useful, eventually. Cart before the horse, otherwise.
Someone needs to bash these scicomm journalists over the head until they stop using the words "artificial sun"
Also, where's the study? Is it even peer reviewed?
Forget artificial suns, let me tell you right now how to make an artificial moon:
- Be a robot.
- Pull down pants.
- Bend over.
- Point robo-crack towards recipient
- Artificial Moon.
While neat, this is not self-sustaining
it's taking more energy to power it than you're getting out of it. (You can build a fusion device on your garage if you're so inclined, though obviously this is much neater than that!)
One viewpoint is that we'll never get clean energy from these devices, not because they won't work, but because you get a lot of neutrons out of these devices. And what do we do with neutrons? We either bash them into lead and heat stuff up (boring and not a lot of energy), or we use them to breed fissile material, which is a lot more energetically favorable. So basically, the economically sound thing to do is to use your fusion reactor to power your relatively conventional fission reactor. Which is still way better than fossil fuels IMHO, so that's something.
the economically sound thing to do is to use your fusion reactor to power your relatively conventional fission reactor
A new one to me. Considering how expensive these are, it would be surprising that traditional Uranium mining/enrichment wouldn't still have an edge. But considering that commercial Tritium is exclusively produced from nuclear reactors, there is a circular money pit economy opportunity.
Helion has an interesting take on fusion reactors that generate power using electro magnetism and Copenhagen Atomics are trying to create Thorium reactors. I hope they will work better than the boiling they use in tocamac reactors
It seems like it's probably too late.
Even if we crack fusion power today, I can't see it being deployed cheaply enough and quickly enough to compete with solar/wind+batteries. By the time we could get production fusion plants up and ready to feed power into the grid, it'd be 2050 and nobody would be interested in buying electricity from it.
moar energy! there will never not be an application for energy production. specifically fusion has the benefit of being highly dense large scale production. which makes it attractive on a number of levels.
Economical energy production, sure, not any energy production. There is a reason we no longer burn wood to heat public baths.
I realize the science marketing of fusion over the past 60 years has been 'unlimited free energy', but that isn't quite accurate.
Fusion (well, at least protium/deuterium) would be 'unlimited' in the sense that the fuel needed is essentially inexhaustible. Tens of thousands of years of worldwide energy demand in the top few inches of the ocean.
However that 'free' part is the killer; fusion is very expensive per unit of energy output. For one, protium/deuterium fusion is incredibly 'innefficient', most of the energy is released as high-energy neutrons which generates radioactive waste, damages the containment vessel, and has a low conversion efficiency to electricity. More exotic forms of fusion ameliorate this downside to a degree, but require rarer fuels (hurting the 'unlimited' value proposition) and require more extreme conditions to sustain, further increasing the per-unit cost of energy.
Think of it this way, a fusion plant has an embodied cost of the energy required to make all the stuff that comprises the plant, let's call that C. It also has an operating cost, in both human effort and energy input, let's call that O. Lastly it has a lifetime, let's call that L. Finally, it has an average energy output, let's call that E.
For fusion to make economical sense, the following statement must be true:
(E-O)*L - C > 0.
In other words, it isn't sufficient that the reaction returns more energy than it requires to sustainT, it must also return enough excess energy that it 'pays' for the humans to maintain the plant, maintanence for the plant, and the initial building of the plant (at a minimum). If the above statement exactly equals zero, then the plant doesn't actually given any usable energy - it only pays for itself.
This is hardly the most sophisticated analysis, I encourage you to look more into the economics of fusion if you are interested, but it gets to the heart of the matter. Fusion can be free, unlimited, and economically worthless all at the same time.
oh boy another economics dweeb who thinks they know what theyre on about. those were a lot of words for a false premise. There is no doubt that fusion can produce more energy than it costs to maintain. we have literal empirical examples of this occurring in nature. You forgetting a significant factor in your analysis: time.
The problem with fusion isnt the science behind its energy production. its the engineering behind the design of plants, unfortunately for fusion it suffers from being fairly unique in that its a high radiation, high heat domain which makes the engineering incredibly difficult to get funded and there isnt anything else comparable to piggy back off of. That's currently your C value and those costs are one time. solar and wind also suffered from this for decades. fortunately those tech could piggy back off discovers in other domains.
The cost of fusion plants and the energy production they'll eventually unlock will disappear soon as we figure out the containment issues, and we're getting close. the reason you're hearing about fusion more and more is because we had a break through in 2010 on superconductors allowing for stronger containment fields.
We've probably spent less than 500 billion globally on fusion research over the entire lifetime of the field. the 'C' value is actually remarkably low economically speaking for the return we'll get.
Even in a world already powered 100% by renewables, fusion is attractive for high energy applications. For a current example see training of LLMs. However there are Industries with immense power requirements like Aluminium smelting that could use fusion power as well.
So far humans have found applications for all energy they were able to produce.
Nah, it'd be quite useful for interstellar travel as but one example I'm helping with.
I think if we figure out nuclear fusion there will be induced demand for energy, in applications that were previously infeasible: desalination via distillation instead of reverse osmosis, direct capture of CO2 from the atmosphere, large scale water transport, ice and snowmaking, indoor farming, synthesized organic compounds for things like carbon sequestration or fossil fuel replacement or even food, etc.
Geoengineering might not be feasible today, but if energy becomes really cheap we might see something different.
This seems like a pipe dream but I don't disagree that it could open up some new applications
The specifics are a pipe dream but the general principle holds: if energy suddenly becomes more plentiful and cheaper by orders of magnitude, society will find a way to use that new plentiful resource in ways that we can scarcely imagine today. That's always been true of new inventions, where much of the post-invention innovation comes in the form of finding new applications for a thing that has already been invented.
Indeed
Long distance transmission creates enormous power wastage, and cities are rarely located in places ideal for large scale wind and solar. Fusion can help deliver power to urban centres, reducing the acreage needed for a solar farm.
There are also inland places in northern latitudes that benefit little from solar. Wind and fusion would be a great energy mix for those places.
Long distance transmission creates enormous power wastage, and cities are rarely located in places ideal for large scale wind and solar. Fusion can help deliver power to urban centres, reducing the acreage needed for a solar farm.
A fusion plant will need either nearby solar or nearby fusion plant, with solar only ok if restarting it can wait until daytime. More likely than not, a fusion plant is needed to help regulate plasma temperature based on reaction rate, and cool magnets. But a 10gw fusion plant still is extremely unlikey to need its output overnight compared to day peak demand. A fusion plant needs to be located near a low property value power plant, instead of close to high property value customers.
Fusion would provide orders of magnitude more power than solar. There's a limit on how much we can practically get from solar, fusion would allow us to exceed that.
There’s a limit on how much we can practically get from solar,
Most residential buildings can self sustain from solar. Dense cities not, but there is dual use grazing and agriculture land, and small desert areas that could power the world. Solar is enough for type 1 civilization. Nuclear plant energy density is overstated due to their + uranium mine exclusion zones, which could produce more solar power than the uranium content available in those mines.
Yeah, but there's no prizes for producing way more power than we use. We're not running out of space to put solar panels or batteries.
'Too much power' has never been an issue, and will likely not be an issue ever with solar. There are multitudes of technologies, especially in industry, that are currently impractical because they would consume too much energy.
In three decades, having a power source that can be placed away from the elements is going to be a very good thing.
Maybe for deep sea or space?
With what infrastructure are we even going to use all this electricity?
There's a ton of stuff in industry and manufacturing that aren't practical because of energy. A lot of processes could be run cleaner too, leading to better environment practices.
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That is one technology that I don't care if China steals secrets to make it happen faster.
No need!
The data gathered by EAST will support the development of other reactors, both in China and internationally. China is part of the International Thermonuclear Experimental Reactor (ITER) program, which involves dozens of countries, including the U.S., U.K. Japan, South Korea and Russia.
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