• Security incident: ISF was recently accessed by intruders. Please change your password, and change it anywhere else you used it. Read more

Merged How Close is power from Nuclear Fusion

Where on earth did you get “free energy” from?

Well, I did see them report that "You get out more energy than you put in", which is probably an oversimplification (and misrepresentation) of the process. If it were bogus, they'd be saying "in 3 to 5 years". Instead, I hear "maybe in 10, 15, 20 years" it will be cost-effective and useful.
 
All the good fuels are more energy out than YOU put in. They all amount to extracting energy put in by other processes. Wood burning keeps people alive in spite of all the calories they have to burn and all the food they have to eat, to collect all that wood. Because the trees and the sun put in most of the energy provision and storage work.

Same with oil.

Same with fusion. The reason fusion is so powerful is because most of the work of storing that energy was done by primordial creation of the universe.
 
Yeah, getting more energy out than you put in (using some sort of fuel or natural energy source) is very different from "free energy" or "perpetual motion" which are prohibited by the laws of physics. That's why we consider the latter claims to be pseudoscience and scams. They are impossible even in principle. Nuclear fusion isn't that, but it is something that is very hard to imagine becoming practical as a source of energy to generate usable electricity for the masses (or anybody for that matter) any time soon.

Whether it is a good investment is debatable.

ITER recently suffered a major setback

A large module (as tall as a six-story building) will have to be removed and repaired, adding further delays and costs to a project that will take decades to complete and won't even produce usable power even if it achieves its goals.

Skepticism is warranted. Not because it is pseudoscience but because it is extremely unlikely to lead to any useful result.
 
I'm not very good at physics, but the article mentioned that such fusion creates helium. Is that true? If so, that might be handy in itself even if it's not useful for power. Helium has a lot of uses and I understand it's getting difficult to find. A quadrillion dollars invested into cold fusion might be worth it if it means we can have guilt-free balloons at parties again! Also I think there's some medical device use as well, but I'm all about balloons.
 
Hate to be a party-pooper, but I would imagine that any helium created as a byproduct would be too small an amount to make a significant difference, and would also be the most expensive way to create helium we could possibly think of. No, I didn't try to do the calculation, it's just a guess. Most helium we get comes mixed in the natural gas we use for fuel.
 
This result, when it is confirmed, is a Big Thing. We've known that over-unity nuclear fusion should be possible - we've had the numbers for that for decades - but this is the first time it has actually been demonstrated in the lab. It's moved from "this is theoretically possible, we just have to work out how to do it" to "we know how to do it now".

There's still a long way to go before fusion power is put on the grid. This is one step among many. But it is a definite step. The concept has been proved. We hadn't had that yet.
 
I'm not very good at physics, but the article mentioned that such fusion creates helium. Is that true? If so, that might be handy in itself even if it's not useful for power. Helium has a lot of uses and I understand it's getting difficult to find. A quadrillion dollars invested into cold fusion might be worth it if it means we can have guilt-free balloons at parties again! Also I think there's some medical device use as well, but I'm all about balloons.

This isn’t about cold fusion at all, just the regular sort which is at least theoretically achievable.
 
A quadrillion dollars invested into cold fusion might be worth it if it means we can have guilt-free balloons at parties again!

This is very, very much about regular fusion and huge lasers. Cold fusion not so much.

And balloons. Of course it's about balloons. The fusion thingy is just a by-product
 
I'm not very good at physics, but the article mentioned that such fusion creates helium. Is that true? If so, that might be handy in itself even if it's not useful for power. Helium has a lot of uses and I understand it's getting difficult to find. A quadrillion dollars invested into cold fusion might be worth it if it means we can have guilt-free balloons at parties again! Also I think there's some medical device use as well, but I'm all about balloons.
Yes, the idea behind nuclear fusion is that you're fusing two hydrogen atoms together to create helium. That's the process which gives off so much energy.
 
Well, I did see them report that "You get out more energy than you put in", which is probably an oversimplification (and misrepresentation) of the process.

Yes, it is. They aren’t counting the potential energy of the fuel in the energy they put in.

The problem for fusion energy is that it takes a lot of energy to start the process, not counting the energy of the fuel. In fact, other than thermonuclear bombs, it usually takes more energy to start it (again, not counting the fuel) than the reaction produces. And that obviously can’t work for power generation. You need the burning of the fuel to return more energy than the spark to light it. And that’s actually really hard to do in a controlled manner. So that’s a minimum theoretical break point to produce power. But in practice, you need to do a lot better than that, because your efficiency in capturing the released energy isn’t 100%, and because you need to get enough back above that to justify the costs. So they have exceeded the bare minimum theoretical floor, but they’re still a long ways off from practical use.
 
This isn’t about cold fusion at all, just the regular sort which is at least theoretically achievable.

Laser ignition fusion is very high temperature. They’ve achieved it in practice quite some time ago. This is a milestone in improving the efficiency, not in doing it at all.
 
Yes, the idea behind nuclear fusion is that you're fusing two hydrogen atoms together to create helium. That's the process which gives off so much energy.

I think the real energy there is love. Those two hydrogen atoms gave birth to a helium, and want only the very best for it!
 
Bah, next thing you know those free energy kooks are going to claim there is a large source of 'free' energy that uses a similar process close by.
They might even claim this energy is fueling most processes on earth for free for as long as the earth exists.
 
Laser ignition fusion is very high temperature. They’ve achieved it in practice quite some time ago. This is a milestone in improving the efficiency, not in doing it at all.

I'm aware (I've actually visited Culham), I was perhaps a little vague but referring to economic power generation as being theoretically possible (as opposed to anything with cold fusion, which, last I knew, has yet to be demonstrated).
 
Last edited:
I'm aware (I've actually visited Culham), I was perhaps a little vague but referring to economic power generation as being theoretically possible (as opposed to anything with cold fusion, which, last I knew, has to be demonstrated).

Well, technically speaking, we haven't yet demonstrated electric power generation with fusion at all. The fusion we can do produces thermal output, and thermal output can be turned into electricity, but to my knowledge that second part hasn't been included in any of the fusion experiments to date. And that's not really a criticism of the experiments, there's really no point in doing that at this stage. If they get the thermal power production to high enough efficiency, then turning it into electricity will be straight forward (we've got a lot of experience turning heat into electricity), but you need to do much better than 1 to 1 input (not counting fuel) to thermal output in order to do better than 1 to 1 input to electrical output, because conversion isn't perfectly efficient even at the theoretical limits and you'll never hit the theoretical limits either.

And THEN you've got to do much better than 1 to 1 input to electrical output in order to make it economically viable.

So we're still at least two major milestones away from the real end goal.
 

ISF - Join now!

Every member here is approved by hand. No bots, no spam, just people who care about evidence and honest debate.

Membership is free!

Create your free account

Back
Top Bottom