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Major breakthrough on nuclear fusion energy

bbc.co.uk

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Re: Major breakthrough on nuclear fusion energy

#571

Post by LocalPCGuy »

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?

Why pick up the passengers only? Plan ahead and build it to pick up the entire ship, including not just the passengers but all the materials and supplies they had packed as well.

Re: Major breakthrough on nuclear fusion energy

#572

Post by andruby »

DennisP wrote: post #496
q1w2 wrote: post #352

Earlier quoted context omitted.

Yep - we're still nowhere near break-even.

We're not that far off. JET previously achieved Q=0.67, ie. two-thirds as much energy output as input. (The new result has higher output but lower Q.) For a practical reactor we need Q around 30, which might seem far away but tokamak output scales with the square of reactor volume and the fourth power of magnetic field strength. Double the field, 16X the output, and we can generate much more powerful magnetic fields…

Any source on that Q=30 requirement for practical reactors?

I’d assume that anything >1 is theoretically “profitable” and something like 2~5 might already be economically viable.

Re: Major breakthrough on nuclear fusion energy

#573

Post by sph »

AtlasBarfed wrote: post #497
dahfizz wrote: post #295

Earlier quoted context omitted.

Wind + Solar are near useless without storage, and we do not have anything close to the storage necessary.

Storage likely will be a non-issue once sodium ion batteries scale up, even cheaper and safer than LFP. A couple more years of scale efficiencies and alt+storage will be cheaper without subsidies. Consumer solar+storage will be cheaper than nat gas in a couple years with any rational subsidy. Land issues? Seriously? The land issue for solar is a non-issue, it's like fake hand-wringing by the oil astroturfers over bir…

You can't say fusion is impractical while saying solar and wind is better by hand waving all the current concerns and technological walls we still haven't solved. Plans on an whiteboard do not count, sorry.

Storage isn't solved, land space isn't solved, efficiency isn't solved, just like fusion isn't a solved problem.

Re: Major breakthrough on nuclear fusion energy

#574

Post by 2OEH8eoCRo0 »

ppaattrriicckk wrote: post #59

In extension to this news and the press conference, one thing I am super excited about, is the private SPARC project and the MIT-spinoff Commonwealth Fusion Systems (CFS). If you don't know about it already, I would highly recommend checking it out (e.g. by searching YouTube for "MIT Sparc Fusion Reactor" for some fairly accessible videos on the theory behind why they should achieve fusion way faster than the current…

I'd love to work at CFS. Cambridge, MA is right down the road from me and there is no greater cause right now than fusion energy in my opinion.

Re: Major breakthrough on nuclear fusion energy

#575

Post by pkulak »

bityard wrote: post #516
tomp wrote: post #503

Earlier quoted context omitted.

Makes you wonder if the US idea of using just 110 volts isn't better... not from an individual viewpoint (slower to boil water) but from the grid perspective.

The US grid (the last-mile bits anyway) isn't 110 volts, it's 220. It's just our houses that are wired for (mostly) 110 V. Edit: I would love to see some sort of hybrid 110/220 V residential wiring/plug standard take hold in the US. It would require more expensive cable in the walls (since you need one additional conductor) and plugs, but it's totally doable. Most electrical products and appliances made these days ar…

I kinda like that all but a couple outlets in my house can't kill me.

Also, I boil my water on an induction stove plugged into 50 amps at 220 volts. I'm not waiting around, to put it mildly.

Re: Major breakthrough on nuclear fusion energy

#576

Post by PaulDavisThe1st »

spywaregorilla wrote: post #537
PaulDavisThe1st wrote: post #449

Earlier quoted context omitted.

> Sure we do. Look no further than this article. We can make it, but its not commercially viable. Q total is way below 1 (translation: it took far more energy to make the energy that was produced, than was produced). We do not have working fusion power, if "working fusion power" means "you get more out than you put in". As for the rest of this, I have no idea who you think you're replying to. Just one follow up, neve…

> Q total is way below 1 (translation: it took far more energy to make the energy that was produced, than was produced). We do not have working fusion power, if "working fusion power" means "you get more out than you put in". That's not what it means. Working means it works. Can you produce fusion power? Yes. Can you do so in a commercially viable way? No. Q is obviously a part of this. Uninteresting semantics. > The…

> Can you produce fusion power? Yes

If it takes more than 1W of input power to produce 1W of power from fusion, then I'd say the answer is no. The distinction is not "commercially viable", it's "net energy production". We're not there yet (and are actually quite a lot way from it).

> And I'm telling you,

... that US$2T is a lot of money, and that's just what we spent on 1 war. Yes, there would be complications and side effects and what have you. Money, in our system, combined with the other abilities of the federal government, can do a lot.

Re: Major breakthrough on nuclear fusion energy

#577

Post by epistasis »

tinco wrote: post #540
ClumsyPilot wrote: post #339

Earlier quoted context omitted.

What does 'fundamentally expensive' mean? If it does not incluse precision engineering to build largest vacuum vessel, supercomputers, superconductors, generation and containment of hottest substance on the planet, and largest magnetic fields we can produce. If that's not 'fundamentally expensive', then what is? Especially when your interlocutor is asking for geothermal, a.k.a. a hole in the ground?

You mean fundamentally expensive like building billions of nano meter scale devices, aligning and wiring 24 million of them to be individually addressable on a 6 inch plane? Oh and we build those by the thousands on factory lines. That's a whole lot more of precision engineering than is needed to build a nuclear fusion reactor, and you can buy it on the order of a hundred bucks. And it's not just a hole in the ground…

I think this is a great example of why fusion will probably not drop in price.

With semiconductors, prices fall continuously because there is continuous iteration, and starting from the very very first lithographic circuits there was a market. There's an entire industry, competitors, and it's a factory system.

Fusion is not like that, it will be like building monuments, there's not thousands or millions of the same thing getting churned out, it will be all specialized construction for each piece.

You may say that a chip did specialized in that each of the transistors re wired together in very specific ways, but the semiconductor industry is a factory factory in some sense, you build a set of masks and that's your factory for your chip.

Let's say you design a fusion reactor, and then 12 months later you see how to shave off 1% of the costs somewhere. That iterative gain is lost, because the fusion reactors will be built very rarely, and building each one in a new custom way poses lots more risk than doing the same design for 10 years. They are just too big and expensive to show the same sort of mass manufacturing gains that can be seen with technologies that have learning curves.

I could be wrong, and I certainly hope I am, but I would bet a hell of a lot more money on a new battery chemistry than I would on fusion as being a terrestrial power device.

Re: Major breakthrough on nuclear fusion energy

#578

Post by coryrc »

btbuilder wrote: post #568
hedora wrote: post #555

Earlier quoted context omitted.

You could just run US-style appliance circuits to your kitchen, etc. Those are sometimes three conductor and other times four conductor. However, I doubt it'd pass inspection if they were easily accessible from the counter-top. If you're going to flout building codes anyway, it'd probably be easier/more practical to just run circuits with foreign outlets instead. Also, it might be easier to find appropriate GFCI brea…

Use 6-15R or 6-20R. I think it would pass inspection because most safety requirements around gfci and afci don’t apply to 240V circuits

They do now, but only when accessible by a person. Even car charging station outlets do (even though every car charging station has gfci built in...)

Re: Major breakthrough on nuclear fusion energy

#580

Post by spywaregorilla »

dymk wrote: post #551
spywaregorilla wrote: post #259

Earlier quoted context omitted.

We haven't invented commercial fusion power, so none; but theoretically that is how they would function. Solar and batteries are nice but they're not yet cost effective. They're getting better. But you can't just handwave away real problems from your armchair viewpoint and assume thats all fine.

> They're getting better. Solar is getting so much cheaper, at such a fast pace, that I really don't understand how one can disagree that it's the future of our energy grids. Installing solar is a no-brainer in some parts of the world now, and in the very near future (extrapolating from the last 10 years), it'll be every part of the world soon. What problems am I hand waving away? https://www.statista.com/chart/26085…

Solar is, without a doubt, a major part of future energy grids.

But this chart is the levelized cost of energy. Its not the price at which you can get it. Energy demands are higher in winter. They are non trivial at night. The cost of energy might be low, but the price at which you can get it may be very high if not enough is available.

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