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Major breakthrough on nuclear fusion energy

bbc.co.uk

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Re: Major breakthrough on nuclear fusion energy

#521

Post by zucker42 »

advisedwang wrote: post #348
johnthesecure wrote: post #303

Earlier quoted context omitted.

That's enough energy to boil those kettles dry, if my calculations are correct. To bring them to the boil, 59MJ would run about 600 kettles.

Water has a specific heat capacity of 4184J/kg/C. Lets say to get to the boil you need to go from 20C to 100C and that a kettle holds 1.75L. 59MJ / (80C * 4184J/kg/C) = 176kg ~= 176L ~= 100 kettles. Water has a latent heat of vaporization of 2260 kJ/kg. So to boil it dry: 59MJ / (80C * 4184J/kg/C + 2260 kJ/kg) = 22kg ~= 22L ~= 12 kettles. I have no idea what the journalist calculated.

I suppose it's possible that the "standard" kettle size is ~3L. They don't seem too uncommon on Amazon.

Re: Major breakthrough on nuclear fusion energy

#522

Post by beefman »

Aeolun wrote: post #315
vcdimension wrote: post #35

They're still a very long way from getting a net gain in energy: https://youtu.be/LJ4W1g-6JiY

Haven’t we already had fusion experiments with net positive energy?

No, unless you count thermonuclear explosives. This experiment didn't demonstrate it either. The fusion only yielded 1/3 the energy used to heat the plasma.[1] That doesn't include the energy needed to run the rest of the machine (magnetic containment etc) and it doesn't include any losses converting the fusion energy to electricity (which was not attempted).

[1] https://www.nature.com/articles/d41586-022-00391-1

Re: Major breakthrough on nuclear fusion energy

#523

Post by bostonsre »

soperj wrote: post #459
bostonsre wrote: post #373

Earlier quoted context omitted.

So are you suggesting he be completely shunned from society? Why not let him try to atone for his sins and try to do good in the world by giving away a large portion of his wealth to noble causes?

I'm suggesting not to hold him or his money in high regard. He's not worth mentioning.

Aren't the causes that he is championing worth mentioning tho? Why is there a need to purge him from current public discourse when he did something bad in the past? I don't think we should disprove of bad people doing good things. Just because he did something bad doesn't mean he can no longer make commendable contributions to society.

Re: Major breakthrough on nuclear fusion energy

#524

Post by soperj »

ambrozk wrote: post #455
worik wrote: post #421

Earlier quoted context omitted.

> Why? He dedicates huge amounts of money to worldwide public health, and is giving away the vast majority of his fortune over the course of his life. Why shouldn't I hold such a person in high regard? We are talking about Bill Gates who because he was better at red in tooth and claw business than technology he held computing back by at least a decade. In 1995 I was using stable 32-bit personal computer software comp…

Okay. Hold your grudge from the 90s. No one can stop you. It's pretty weird not to care about his enormous efforts in philanthropy, though.

How much of it is even his money and not Warren Buffett's money?

Re: Major breakthrough on nuclear fusion energy

#525

Post by JohnJamesRambo »

yholio wrote: post #284
Aperocky wrote: post #248

> This is more than double [the energy] what was achieved in similar tests back in 1997. I was excited for a little bit there.

Yup, a major breakthrough in this glacial field is doubling the energy output in 25 yeas. So by the time captain Picard is born, we might have a very expensive and massive fusion reactor that will generate the same kind of energy we can generate today with very expensive and massive fission reactors. Really now, this is pure garbage and does not solve the major problems in the field nor do most of the myriad startups…

Sometimes I wonder what would happen if we put the massive amounts of money we have put into nuclear fusion and fission into bone simple solar panel purchases. I wonder if anyone has done the math.

There’s a fully functioning fusion reactor 91 million miles from us that sends a lot of energy our way.

Re: Major breakthrough on nuclear fusion energy

#526

Post by bityard »

soheil wrote: post #401
ComputerGuru wrote: post #297

> It's not a massive energy output - only enough to boil about 60 kettles' worth of water. This made me laugh. How much more British can you get?

You'd probably be surprised to learn that the UK is not at the top of the list of countries with the highest tea consumption. https://en.wikipedia.org/wiki/List_of_countries_by_tea_consu...

Ireland is #2? As a culturally ignorant American, that _does_ surprise me.

Re: Major breakthrough on nuclear fusion energy

#527

Post by Retric »

34679 wrote: post #495
moron4hire wrote: post #406

Earlier quoted context omitted.

Did you factor in the inefficiencies of the power distribution grid and the heating element of the kettle? I'd say the journalists are just repeating what they've been told by the scientists, and the scientists factored inefficiency in on a calculation similar to your first.

There may exist inefficiencies in the transfer of heat from the element to the water, but there is no such thing as an inefficient heating element. All of the power it uses will be converted to heat. Take a light bulb for example. When used to light a space, the inefficient part would be the energy that is lost to heat. The rest is converted to light, but as soon as that light hits an object, it's converted to heat.…

The internal heating element isn’t strictly speaking 100% efficient on AC as it’s producing a changing electric field etc. It’s just generally ignorable in practical terms.

Re: Major breakthrough on nuclear fusion energy

#528

Post by ninkendo »

willis936 wrote: post #320
ninkendo wrote: post #312

Earlier quoted context omitted.

What's nice is that even for Q_plasma this only gets 0.33. So it's a net loss no matter how you measure it.

I'm confused. What do you think the goal of the campaign was?

It's tough to say because the campaign is a signpost on the way to an eventual end goal. But the end goal is easy to describe: "a working fusion power plant."

The end goal is so far away at this point, not a single player in this space is even trying to do it, even on their farthest-out roadmaps...

Re: Major breakthrough on nuclear fusion energy

#529

Post by MertsA »

Axien wrote: post #340

I noticed the waste output is helium. Does this fix the worldwide helium scarcity issue?

No, there's very little helium produced for the same reason that fusion generates massive amounts of energy from very tiny amounts of fuel. In fact there'd be more helium produced in the nuclear reactor generating the tritium than there would be in the fusion reactor burning it. Eventually commercial nuclear fusion reactors will generate their own tritium from a lithium blanket but for now that's all from fission reactors.

Re: Major breakthrough on nuclear fusion energy

#530

Post by antod »

guhidalg wrote: post #329
treis wrote: post #251

Earlier quoted context omitted.

It runs into the spaceship problem where later iterations of a spaceship reach the destination first because new technology allows them to fly faster. At some point (maybe) materials and other technology will develop enough so that fusion becomes feasible on a decades or so timeline. Or solar & battery technology will develop to the point where fusion isn't really needed.

It's an interesting sci-fi thought, but why wouldn't the second spaceship just catch up with the first one and pick up the passengers to avoid their unnecessary travel time?

Because you'd have to leave the 2nd one nearly empty to fit the extra passengers in?

Might be a good idea if nobody wants to go on the 2nd ship though.

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