Major breakthrough on nuclear fusion energy - BBC News

[Commodus]

Like Mendicant so helpfully said — the issue with fusion energy is not its safety. It's the sheer technical challenge of providing fusion power that can sustain whole cities. This effort is a significant step forward, but I agree with other that it could be decades before fusion is practical. Right now the best energy solution is likely a combo of renewables with small-but-relatively-safe nuclear reactors.

[Tech Enthusiast]

3 hours ago, tikker said:

My favourite example of this is how my professor introduced stellar fusion: stars aren't hot because they have fusion,  they have fusion because they are hot".

That is gonna be my favorite description for this issue going forward as well. Very well put and easily understandable. Can't count how many people I have talked to that think endless energy automatically mean big earth destroying boom at the same time.

 

Now, once that thing is running we can obviously use that energy to build an actual weapon,... and obviously the USA will do that (for self defence, no doubt...), but the tech behind the energy generation is not unsave in itself. You can't control what people and countries do with the output tho.

[Imbadatnames]

1 hour ago, Commodus said:

Like Mendicant so helpfully said — the issue with fusion energy is not its safety. It's the sheer technical challenge of providing fusion power that can sustain whole cities. This effort is a significant step forward, but I agree with other that it could be decades before fusion is practical. Right now the best energy solution is likely a combo of renewables with small-but-relatively-safe nuclear reactors.

Fission reactors are perfectly safe and large plants are reliable and the most green power generation we currently have. 

[Tech Enthusiast]

22 minutes ago, Imbadatnames said:

Fission reactors are perfectly safe and large plants are reliable and the most green power generation we currently have. 

Almost all true, apart from "we currently have" because we don't. We want them. But I do want numerous things and still don't have them, right now.

[dizmo]

What's the long standing joke? Nuclear fusion is always about 30 years away? 

[Tech Enthusiast]

8 minutes ago, dizmo said:

What's the long standing joke? Nuclear fusion is always about 30 years away? 

Its really not. It is just not an easy to do thing and people outside of research have a very short time window they pay attention to.

Basically, if it takes longer than a week, it is boomer stuff.

[Imbadatnames]

25 minutes ago, Tech Enthusiast said:

Almost all true, apart from "we currently have" because we don't. We want them. But I do want numerous things and still don't have them, right now.

We’ve had fission reactors since the 50’s/60’s? 

[Tech Enthusiast]

10 minutes ago, Imbadatnames said:

We’ve had fission reactors since the 50’s/60’s? 

And all of those proved to be as perfectly safe and secure as you suggested? Yes?

The best we can do is build new ones that are MUCH more save, but "perfectly save" is far off. As long as a meltdown can happen, the possible fallout is just way too big to call it save.

 

If the worst that could happen was a sick person in the plant, we could call that perfectly save. If a "woopsie!" could lead to several hundred thousand dead people AND a dead piece of land for centuries, it is hard to call it perfectly save.

[Imbadatnames]

7 minutes ago, Tech Enthusiast said:

And all of those proved to be as perfectly safe and secure as you suggested? Yes?

The best we can do is build new ones that are MUCH more save, but "perfectly save" is far off. As long as a meltdown can happen, the possibly fallout is just way too big to call it save.

 

If the worst that could happen was a sick person in the plant, we could call that perfectly save. If a "woopsie!" could lead to several hundred thousand dead people AND a dead piece of land for centuries, it is hard to call it perfectly save.

There’s been 3 major meltdowns in the history of nuclear power, 51 deaths between them. 50 of those from Chernobyl which we chased by doing an experiment that really shouldn’t have happened at a time other than the scheduled test date. The other was Fukushima which took an earthquake and a tsunami to trigger into meltdown that was largely contained. So basically don’t build them near places at risk of a tsunami. 
 

To put that into context solar panels kill about 100-150 people a year

[Tech Enthusiast]

6 minutes ago, Imbadatnames said:

To put that into context solar panels kill about 100-150 people a year

Oh boy. I guess we can stop right there.

Solar panels killing more people than all the nuclear accidents haha.

"If I don't see a person dying, it did not die!" kinda arguments are not exactly a debate I am willing to partake in. I will leave that to US political debates and other comedy shows.

[Mark Kaine]

1 hour ago, Imbadatnames said:

Fission reactors are perfectly safe and large plants are reliable and the most green power generation we currently have. 

yeah, so how many are currently online?

And you cant just say they're safe when that isnt proven in practice at all, they said the same about current nuclear power plants… 

[Kisai]

7 hours ago, J-from-Nucleon said:

So, exactly how close are we to break-even?

 

Not close enough for commercial production.

 

The problem isn't that Fusion is inefficient to build and start, but that it's inflexible. Once you have a fusion reactor producing energy, you have to use 100% of that output, you can't just dial it down for off-peak. 

 

Like maybe within a decade there will be commercially operating reactor. But we can't get there fast enough because coal is still too cheap to burn and idiots are still destroying all the energy savings gained in the last decade on crypto-scams.

[IPD]

1 hour ago, Imbadatnames said:

There’s been 3 major meltdowns in the history of nuclear power, 51 deaths between them. 50 of those from Chernobyl which we chased by doing an experiment that really shouldn’t have happened at a time other than the scheduled test date. The other was Fukushima which took an earthquake and a tsunami to trigger into meltdown that was largely contained. So basically don’t build them near places at risk of a tsunami. 
 

To put that into context solar panels kill about 100-150 people a year

All of those were fission based.  But we've had a LOT of nuclear related accidents.  And the death-toll is WAY higher than this small snippet will tell you.  Stuff that if you knew about how close we came to disaster, it would keep you up at night.  The UK could be a wasteland right now.....

 

https://en.wikipedia.org/wiki/International_Nuclear_Event_Scale

[Imbadatnames]

45 minutes ago, IPD said:

All of those were fission based.  But we've had a LOT of nuclear related accidents.  And the death-toll is WAY higher than this small snippet will tell you.  Stuff that if you knew about how close we came to disaster, it would keep you up at night.  The UK could be a wasteland right now.....

 

https://en.wikipedia.org/wiki/International_Nuclear_Event_Scale

Deaths directly caused by nuclear meltdowns? That’s 31. 31 from Chernobyl 0 from Fukushima. 
 

Dude you’re quoting Wikipedia. Also you’re not understanding how severe the scales are. Until you hit the upper tiers there’s not really a massive issue. You should also look at the dates of the incidents. Aside from Fukushima the latest one is in the 80’s and the majority are from the 50’s. You’re just seeing “nuclear” and getting scared. We don’t live in a fallout game, radiation isn’t that bad for the most part. If you’re not swimming in a short term storage pool you’re probably fine. 

[Imbadatnames]

1 hour ago, Mark Kaine said:

yeah, so how many are currently online?

And you cant just say they're safe when that isnt proven in practice at all, they said the same about current nuclear power plants… 

440 according to google out of 667 built. They have a life expectancy of around 40 years though I think? Though that can be extended if it’s still in good condition to operate and maybe needing some upgrades. 
 

They are safe? The reason there’s not more is due to misplaced fear of nuclear power from WMDs and Chernobyl being massively overblown by the western media as it was on the other side of the iron curtain and 3 mile island in the US. The only issue with a modern reactor has been Fukushima and that took 2 natural disasters to force it into meltdown where it was contained with 0 deaths and so little radiation you can grown crops in the soil around the plant and them meet food standards. 
 

 

[Fnige]

4 minutes ago, Imbadatnames said:

and so little radiation you can grown crops in the soil around the plant and them meet food standards

Oooo new business idea /s

[CarlBar]

@Master Disaster Kind of disappointment to see you doomongering, you've generally shown yourself to be pretty smart and level headed.

 

Let me try and cover a bunch of the involved science for you.

 

The first thing you have to understand is that in a steady state system energy in equals energy out. Any functioning reactor is going to have as much energy leaving it every second as is being generated inside it. iI's a functional requirement of a working design. This also applies to modern power generators. In fact due to efficiency limits it's often several times the electrical output. A simple 1GW level electrical plant will be pumping several GJ's of thermal energy into the system every second.

 

That sounds like a lot. But a 1 Kiloton Nuke releases around 4.5TJ's of energy in a few millionths of a second. The time period is what allows it to generate such a strong shockwave. A Thermal Power plant, (like a fusion reactor, but you could absolutely get the same effect with fossil fuels on paper, it just requires a scale no one would try), would need to be produces tens, possibly hundreds of times as much thermal energy to get the same effect from a sustained release. (Energy to destruction ratio is a complex field and the fine details are outside my purview, but a good general rule is you need a much larger release over a long period of time to get the same effect as one very quick release in an instant, but it doesn't scale lineally to the time scale difference).

 

Thus to get even a 1Kt explosion equivalency would need a reactor with enough thermal energy that using a realistic thermal to electrical efficiency value you could power the entire earth off it two or three times over. No one's looking to build a reactor with anything like that kind of energy output. Something on par with the biggest nuke bomb ever detonated would be able to produce enough electricity in normal operation to power the earth a million times over or more. And would consume well in excess of 1500 tons of Hydrogen a second, (Thats roughly the hydrogen content of 15,000 tons of water a second).

 

 

Now that doesn't mean there aren't smaller scale explosion possibble, but there are plenty of industrial accidents in that range routinely, thats why safety zones around such things exist.

 

Now it's true that the energy going in isn't all the energy in the system. The higher the temperature of the walls of the reactor the faster the rate of transfer per surface area to the coolant. Thermal transfer rates scale with the temperature difference in the absence of any outside effects, (boundary layer effects for example). But that same limit of transfer to coolant means that whilst a catastrophic incident can allow it to dump energy faster than say it does to coolant in normal operation, it can't dump it's entire energy content in a tiny fraction of a second. there's a still a danger that a sudden vacuum failure in the core of a fusion reactor could cause a shock-wave from the air rushing in getting suddenly heated from contact with the walls of the reactor. But again where talking a slow release of a total amount of energy that doesn't even come close to nuclear bomb levels in any reasonably sized reactor.

 

In the end the dangers aren't really any more severe than a steam boiler of the same thermal power level. The only worry point is excessively sized reactors, but even then where talking fractions of a kiloton at absolute worst, and nothing that scale will be built anytime soon because there's no possibble demand for such a monster of an electricity source. Even china would struggle to utilise a 1TW reactor.

 

 

Useful notation:

 

1J for one second = 1W

 

4.5MJ's = 1KG of TNT

 

1GW = 1,000MW's

 

1TW = 1,000GW's, or 1,000,000MW

 

Tsar Bombn, (biggest Nuke) = 225,000TJ's

 

Total Earth Electricity Consumption: Around 5TW's

[dizmo]

2 hours ago, Tech Enthusiast said:

Its really not. It is just not an easy to do thing and people outside of research have a very short time window they pay attention to.

Basically, if it takes longer than a week, it is boomer stuff.

No, I'm right.

https://www.discovermagazine.com/technology/why-nuclear-fusion-is-always-30-years-away

[Tech Enthusiast]

29 minutes ago, dizmo said:

No, I'm right.

https://www.discovermagazine.com/technology/why-nuclear-fusion-is-always-30-years-away

So, an article that basically says: "there have been setbacks in research of a new technology", is your basis on being "right" on it never releasing ever? Because that is exactly what "always 30 years away" suggests. It will never get there.

 

That is a pretty low bar as far as "proof" goes, man.

[Quackers101]

4 minutes ago, Tech Enthusiast said:

So, an article that basically says: "there have been setbacks in research of a new technology", is your basis on being "right" on it never releasing ever? Because that is exactly what "always 30 years away" suggests. It will never get there.

not in never releasing, only that you will hear about an "Major breakthrough" every year for the next 30 years

just don't look into how many threads there is already in tech news on the LTT forum.

[Tech Enthusiast]

Well, there have been major breakthroughs,... that is not what "always 30 years away" means at all.

We will get breakthroughs at an increasingly fast pace. That does not mean "it is done and works!", it just means another hurdle has been beaten.

There is more than one challenge in getting theoretical infinite power.

[Quackers101]

5 minutes ago, Tech Enthusiast said:

Well, there have been major breakthroughs,... that is not what "always 30 years away" means at all.

We will get breakthroughs at an increasingly fast pace.

sure, sorta. Also its just a meme at this point, like there is still quite long before it becomes a "thing" even if there is a lot of breakthroughts. then there is to build these giant buildings for it and getting the power needed, batteries to store everything and so on. Although some of these methods might be earlier out the door or around fission

[Guest]

We already have a HUGE ass power plant in the sky, err in space. Which gives us plentiful amounts of energy. 

 

Instead of spending money trying to find better ways to collect it, lets build a sun and hope it doesn't implode into a black hole and suck all our hopes and dreams away.

 

 

[Guest]

10 minutes ago, Tech Enthusiast said:

Well, there have been major breakthroughs,... that is not what "always 30 years away" means at all.

We will get breakthroughs at an increasingly fast pace. That does not mean "it is done and works!", it just means another hurdle has been beaten.

There is more than one challenge in getting theoretical infinite power.

The time line is actually dead wrong.

 

It's at least 300 years away.

[CarlBar]

43 minutes ago, Tech Enthusiast said:

Well, there have been major breakthroughs,... that is not what "always 30 years away" means at all.

We will get breakthroughs at an increasingly fast pace. That does not mean "it is done and works!", it just means another hurdle has been beaten.

There is more than one challenge in getting theoretical infinite power.

 

Yes but there have been breakthroughs heralded as "fusion is only 20-30 years away" ever since serious research into the idea started in the 60's and 70's. The problem is every-time we think we've got it figured out it turns out some aspect doesn't scale up right. Recently it's been an issue of keeping the plasma contained in the magnetic fields, (for magnetic confinement designs), it turns out plasma is a lot better at leaking out of a magnetic field than we anticipated and accounting for and compensating for that has repeatedly set things back as we've attempt to scale size and duration of the fusion towards usable sustained levels.

 

Before that it was the energy input required didn't scale to large masses of fuel from smaller masses as expected.

 

Plus a whole host of other minor niggles that have cropped up that we didn't see coming ahead of time. Turns out getting the laws of physics to let us do sustained fusion without the crushing gravity of the sun to squash, heat and hold everything together is surprisingly difficult.