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First Light (Oxford University spinout) achieves nuclear fusion

firstlightfusion.com

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Re: First Light (Oxford University spinout) achieves nuclear fusion

#61

Post by oneoff786 »

sandworm101 wrote: post #43
nsxwolf wrote: post #26

Earlier quoted context omitted.

It's so cool, though. The power of the sun, in the palm of my hand!

Solar panels harness the power of the sun too. Fun fact: The sun's energy density is only a few watts per ton. A thousand-pound chunk of the sun could barely run a flashlight. Practical fusion requires H/He conversion rates exponentially faster than stars. Yes, i meant to say power density rather than energy. My bad.

Your hand, can in fact, harness the power of the sun’s power by receiving warmth on its own.

Re: First Light (Oxford University spinout) achieves nuclear fusion

#62

Post by oneoff786 »

androa wrote: post #58
darkwater wrote: post #6

As a nuclear fusion ignorant, where is the small print here? What's the catch, drawback, issue that it will make actually nonviable ?

Short story, they are shooting small plastic cubes with gas inside. The cubes are called "targets". The "bullet" is fast enough to compress the gas inside the cube, creating fusion. It works. But in the scenario it does work, a machine is manually opened, loaded, prepared, and then they do the shot. Whole process takes days to prepare. For it to be viable they need to do this every five seconds. That is a hard proble…

Ok. So dumb question. What complicates this beyond a conceptual belt fed heavy machine gun?

Re: First Light (Oxford University spinout) achieves nuclear fusion

#63

Post by hyperbovine »

sandworm101 wrote: post #43
nsxwolf wrote: post #26

Earlier quoted context omitted.

It's so cool, though. The power of the sun, in the palm of my hand!

Solar panels harness the power of the sun too. Fun fact: The sun's energy density is only a few watts per ton. A thousand-pound chunk of the sun could barely run a flashlight. Practical fusion requires H/He conversion rates exponentially faster than stars. Yes, i meant to say power density rather than energy. My bad.

It would run your flashlight until basically the end of time though. I think you neglected that small point.

Re: First Light (Oxford University spinout) achieves nuclear fusion

#64

Post by ncmncm »

car_analogy wrote: post #59
ncmncm wrote: post #34

Earlier quoted context omitted.

Cynicism is well justified, given history and the present landscape. Suppose they get this working, and able to produce, what, 300 MW worth of hot neutrons. They have to capture the neutrons and turn them into heat to boil water to drive a turbine to get out 150 MW. Thus, handle the, what, 1000 tons? 10,000 tons? of lithium needed to capture all those neutrons. And, I guess, sieve it for tritium? Maybe chemically sep…

> Cynicism is well justified, given history and the present landscape. The history, measured by the fusion triple product, is exponential progress on par with Moore's law [1], despite abysmal funding [2]. [1] Figure 1, https://www.scipedia.com/public/Sanchez_2014a [2] https://hardware.slashdot.org/story/12/04/11/0435231/mit-fus...

The history is of radical overpromising, and continual announcement of "breakthroughs" that do not bring plausible competitive viability any nearer.

The current funding level, given the abysmal prospects for any return, is too high. It was even higher before. We'll never get any of that back.

Re: First Light (Oxford University spinout) achieves nuclear fusion

#65

Post by car_analogy »

ncmncm wrote: post #64
car_analogy wrote: post #59

Earlier quoted context omitted.

> Cynicism is well justified, given history and the present landscape. The history, measured by the fusion triple product, is exponential progress on par with Moore's law [1], despite abysmal funding [2]. [1] Figure 1, https://www.scipedia.com/public/Sanchez_2014a [2] https://hardware.slashdot.org/story/12/04/11/0435231/mit-fus...

The history is of radical overpromising, and continual announcement of "breakthroughs" that do not bring plausible competitive viability any nearer. The current funding level, given the abysmal prospects for any return, is too high. It was even higher before. We'll never get any of that back.

> The history is of radical overpromising, and continual announcement of "breakthroughs" that do not bring plausible competitive viability any nearer.

It sounds like your issue is with the PR, not the technology. Is there something faulty or misleading with the progress made in the triple-product score?

> The current funding level, given the abysmal prospects for any return, is too high. It was even higher before. We'll never get any of that back.

30 years of fusion research is what a single Nimitz aircraft carrier costs. The "even higher" level was one Nimitz carrier per decade. And it only lasted one decade. Eyeballing the funding graph, the US has spent a total of 3 aircraft carrier's worth of funding for fusion in total, since research began.

Re: First Light (Oxford University spinout) achieves nuclear fusion

#66

Post by bell-cot »

DennisP wrote: post #55
bell-cot wrote: post #41

Earlier quoted context omitted.

Roughly speaking, the catch with every fusion-related "breakthrough" in the past 60+ years is the not-so-slight difference between: - "With a huge research budget, we found a nifty new way to reliably set a few tiny lumps of coal on fire in our lab." and - "We can reliably build useful and practical locomotives, ships, and electrical generating plants which are powered by burning coal... and are long-term economicall…

Here's something modestly bigger: the UK's JET reactor recently produced 11 megawatts for five seconds. https://www.mpg.de/18250857/jet-fusion-facility-new-world-en... The plasma was stable and they could have gone longer except instead of superconductors, JET uses copper coils that would melt if they went longer. Their input energy was about three times their total output. But fusion output scales with the square of…

Wikipedia notes that JET produced 10MW of fusion power, sustained for 0.5 seconds, back in 1997. If that real-world rate of improvement continues, it'll reach 12MW for 50 seconds in 2047, and 13MW for 500 seconds in 2072.

Meanwhile, a set of 5 30-year-old diesel-electric railroad locomotives can reliably put out ~10MW of usable electrical power (vs. thermal production). Vastly cheaper, with a proven track record and 100% duty cycle. (Generously figuring 3 running, 1 standby, 1 down for maintenance.)

( Wikipedia reference on JET: https://en.wikipedia.org/wiki/Fusion_power#1990s )

Re: First Light (Oxford University spinout) achieves nuclear fusion

#68

Post by ncmncm »

car_analogy wrote: post #65
ncmncm wrote: post #64

Earlier quoted context omitted.

The history is of radical overpromising, and continual announcement of "breakthroughs" that do not bring plausible competitive viability any nearer. The current funding level, given the abysmal prospects for any return, is too high. It was even higher before. We'll never get any of that back.

> The history is of radical overpromising, and continual announcement of "breakthroughs" that do not bring plausible competitive viability any nearer. It sounds like your issue is with the PR, not the technology. Is there something faulty or misleading with the progress made in the triple-product score? > The current funding level, given the abysmal prospects for any return, is too high. It was even higher before. We…

3 aircraft carriers in, 0 kWh out.

Re: First Light (Oxford University spinout) achieves nuclear fusion

#69

Post by bell-cot »

mcronce wrote: post #54
bell-cot wrote: post #41

Earlier quoted context omitted.

Roughly speaking, the catch with every fusion-related "breakthrough" in the past 60+ years is the not-so-slight difference between: - "With a huge research budget, we found a nifty new way to reliably set a few tiny lumps of coal on fire in our lab." and - "We can reliably build useful and practical locomotives, ships, and electrical generating plants which are powered by burning coal... and are long-term economicall…

Fusion research has not received anything even remotely resembling "all the $Billions in the world"

Literally you are correct - that phrase is a bit of English-language rhetoric.

But neither has fusion power shown anything even remotely resembling the real-world promise of fission power - which went from the first major attempt at a proof-of-concept reactor (Chicago Pile-1, Dec. 1942, ~1/2 watt thermal power output) to powering a large, high-performance warship (USS Nautilus, Jan. 1955, ~10MW on the propeller shafts) in just 12 years.

Re: First Light (Oxford University spinout) achieves nuclear fusion

#70

Post by DennisP »

bell-cot wrote: post #66
DennisP wrote: post #55

Earlier quoted context omitted.

Here's something modestly bigger: the UK's JET reactor recently produced 11 megawatts for five seconds. https://www.mpg.de/18250857/jet-fusion-facility-new-world-en... The plasma was stable and they could have gone longer except instead of superconductors, JET uses copper coils that would melt if they went longer. Their input energy was about three times their total output. But fusion output scales with the square of…

Wikipedia notes that JET produced 10MW of fusion power, sustained for 0.5 seconds, back in 1997. If that real-world rate of improvement continues, it'll reach 12MW for 50 seconds in 2047, and 13MW for 500 seconds in 2072. Meanwhile, a set of 5 30-year-old diesel-electric railroad locomotives can reliably put out ~10MW of usable electrical power (vs. thermal production). Vastly cheaper, with a proven track record and…

As I mentioned above, fusion output scales with reactor size and magnetic field strength, and five seconds is the limit of their copper coils. There's no way for JET to significantly change any of that, so I don't know why you'd expect large improvements from them.

After 1997, the only way to scale up was reactor size, and that started with ITER, the 20-story-tall reactor in France. That soaked up a lot of fusion money, has been slow to build, and it's still not running. But more recently REBCO hit the market, and the same scaling laws say a reactor smaller than JET using those should get substantial energy gain. Two projects are building such reactors, and at least one will be ready around 2025.

(In any case, I wouldn't say five diesel locomotives are comparable to "burning a few tiny lumps of coal.")

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