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Major breakthrough on nuclear fusion energy

bbc.co.uk

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Re: Major breakthrough on nuclear fusion energy

#771
post #401

> 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...

The source at the origin of the data is paywalled but there’s no way this is representative. Japan and Taiwan surely must have higher consumption than that. As someone else noted, wouldn’t be surprised if this is purely based on import statistics and therefore ignores domestic consumption.

Re: Major breakthrough on nuclear fusion energy

#772
post #613
post #587

Earlier quoted context omitted.

30A at 400V is how we roll in the EU.

Wow. A typical induction hob in the UK is 32A at 230V. 230V is of course the nominal voltage of a single phase, although in practice in the UK the voltage is closer to 240V. That's only 7.35kW of power. Do you have significantly more powerful cookers?

these are 3-phase stoves, they require a certified electrician to install, because they don't have plugs and there's no wall socket - just a place into which you can easily connect cables.

Re: Major breakthrough on nuclear fusion energy

#773
post #632

I am a strong proponent of Fusion energy and did some work on the subject in undergrad. This is not a major breakthrough, it's a benchmark. A major breakthrough would be materials that could withstand the neutron bombardment longer, the ultimate limiting factor for fusion energy plants after we achieve positive net energy.

You will find, especially after reading the comments, that fusion is not about creating electricity (it never will), it is about sparking people's imagination. Many people grew up reading science fiction and there is seriously nothing it the last 50 years that comes close to the amazing breakthroughs in the physical world that happened in the 50 years before that. The idea of fusion is the best thing going right now.…

Lol I wonder if anyone ever said this about flying.

Re: Major breakthrough on nuclear fusion energy

#774
post #560

Earlier quoted context omitted.

ReBCO tape is the specific high-temperature superconducting material they're using. Another important material is FLiBe, which is a liquid that I think absorbs the energy from the fusion reactor. I don't really understand the properties that make it particularly well suited to the task, but I gather it's important. https://en.wikipedia.org/wiki/Rare-earth_barium_copper_oxide https://en.wikipedia.org/wiki/FLiBe

According to the article, FLiBe has the same heat capacity of water, but a boiling point over 14x higher (1430 °C according to the article). Melting point is 359 °C, 3.5x higher. I will speculate that its basically used as a water coolant with the phase shifts shifted up and out. I bet the heat exchangers are exotic, too, having to operate at such high temps! In fact I'd expect to see a pretty sophisticated cascade o…

Nitpick, ratios of °C do not make physical sense. For ratios of temperatures you should first convert them to Kelvin, Rankine, or something similar.

Accordingly, the ratio of 1430°C to 100°C is roughly 1703/373=4.6.

Re: Major breakthrough on nuclear fusion energy

#775
post #156
post #116

Earlier quoted context omitted.

Imagine you live in a smallish, not-so-sunny country like the UK. How much of your land area do you have to cover with solar panels in order to completely rid the nation of fossil fuels?

Fun fact - solar energy production over a year only differs by a factor of 4 between worst and best reasonably inhabited places.

> only differs by a factor of 4

how is a factor of 4 "only". It's absurdly high.

Re: Major breakthrough on nuclear fusion energy

#776
post #751
post #711

Earlier quoted context omitted.

There is a class of problems that I've become accustomed to being forever in the future. - Nuclear Fusion - AGI - Driverless cars - Quantum Gravity - Carbon Nanotubes There appears to either be a problem where these are either convenient money sinks, problems that are missing key break-throughs or missing critical technologies. Nuclear Fusion would be easy if we had 400T magnetic fields and the structures to support…

Used to be on the list: reusable rockets, reasonably priced electric cars with charging infrastructure, rapid development of new vaccines with direct genetic engineering mechanisms.

Flying cars

Re: Major breakthrough on nuclear fusion energy

#777
post #711
post #646

Earlier quoted context omitted.

I used to like the idea of fusion energy, but practical application has always seemed to be 40 years in the future, and it's starting to sound more like 60 years now. I hope it will be possible some day, but it's not going to help with out energy needs in our lifetime. (Unless that longevity research is going to pay off, I guess.)

There is a class of problems that I've become accustomed to being forever in the future. - Nuclear Fusion - AGI - Driverless cars - Quantum Gravity - Carbon Nanotubes There appears to either be a problem where these are either convenient money sinks, problems that are missing key break-throughs or missing critical technologies. Nuclear Fusion would be easy if we had 400T magnetic fields and the structures to support…

I've heard of horses taking their blackout/drunken owners home before. CHECKMATE DRIVERLESS VEHICLES

Re: Major breakthrough on nuclear fusion energy

#778

Earlier quoted context omitted.

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…

> For a practical reactor we need Q around 30 Did we figure out how we could harness the energy released? It appears to me that all current research are about maximizing Q without really looking at how the energy will be converted into usable form.

For D-T fusion, the output is 80% neutrons, so the only option is to let them heat something to run a turbine. You also need the neutrons for breeding the tritium, so you let your breeding blanket heat up and run coolant pipes through that. Commonwealth plans to use molten FLiBe salt as the breeding blanket and first loop of coolant.

Aneutronic fusion produces fast-moving charged particles instead of neutrons, so if anyone gets that working, we could extract electricity without a thermal cycle.

Re: Major breakthrough on nuclear fusion energy

#780
post #772
post #613

Earlier quoted context omitted.

Wow. A typical induction hob in the UK is 32A at 230V. 230V is of course the nominal voltage of a single phase, although in practice in the UK the voltage is closer to 240V. That's only 7.35kW of power. Do you have significantly more powerful cookers?

these are 3-phase stoves, they require a certified electrician to install, because they don't have plugs and there's no wall socket - just a place into which you can easily connect cables.

That makes sense. In the UK you can buy induction hobs that plug into sockets, but they are limited to a measly 3.7kW or there abouts. A nicer 32A induction hob needs hardwired (single phase).

You can have upgrade your domestic supply to three phrase, but AFAICT it's uncommon. Perhaps with electric cars and induction hobs replacing natural gas and petrol, it will become more common.

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