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Will we ever get fusion power?

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Re: Will we ever get fusion power?

#281

Post by walleeee »

derriz wrote: post #276
walleeee wrote: post #273

Earlier quoted context omitted.

> You really believe it would have been possible to construct a modern wind turbine with the materials available in 1950? Sure, modern materials make for a more modern wind turbine. But they don't shift the paradigm. Nothing has since fission, right? > Wind, solar and batteries are products of an energy intensive process NOT a combustion based process. The fact remains that energy intensive industry is currently acco…

Modern wind turbines absolutely have shifted the paradigm - both in size, efficiency and durability. Across the globe, demand for new turbines in the market is insatiable. No other electricity generation technology (even nuclear in its heyday back in the 1980s) has grown as fast as wind has in the last 15 years - although I expect it's soon to be overtaken by PV growth. It's likely that this year the amount of electr…

It's not enough to count the problems in the list, you also weigh the ones it solves against those it introduces. I'm not a nuclear engineer, but none of the issues seem insurmountable, and some are addressed in modern designs. I see a few big advantages:

1) Apparently much lower resource requirements for construction, maintenance, and mining/refining the fuel, than for traditional nuclear power, and also (!) the wind and solar equivalent. We don't have the metals, as far as we know, to maintain a fleet of wind turbines, solar panels, and batteries for very long without an almost perfect recycling rate.

2) Some designs can consume spent nuclear fuel. This is a more cost-effective (and more sane) option for disposing nuclear waste than burying it.

3) Steady availability. Wind and solar are unreliable, so you need a buffer, which means batteries (or pumped hydro, or rapidly spinning hunks of metal, or something).

Mass production is a force to be reckoned with, and the cost of wind and solar has fallen relative to other power sources, but given the dominance (still) of combustion, this not only reflects economies of scale in manufacturing wind/solar equipment, which I don't by any means deny, but it reflects also the rising costs of of legacy fuels. It is not getting easier to find coal, oil, or many of the metals we use to manufacture energy systems and the material economies they sustain.

It seems to me we need an energy system that can function reliably in a world facing resource shortages and other stressors, and in this context smaller scale, modular power plants may even be an advantage.

I know TMSR-LF1 is small and a research program; I thought it had sold some power, but might have been misinformed

Re: Will we ever get fusion power?

#282

Post by pfdietz »

Retric wrote: post #123
7thaccount wrote: post #116

Earlier quoted context omitted.

There will be times when the wind doesn't blow and the sun doesn't shine. Storage can come to the rescue if this is a few hours, but over much longer time periods will be a problem. It's rare, but not unheard of. Gas will be part of the solution for many years to come.

> over much longer time periods It’s not clear there would be much longer time periods. Build enough low carbon generation to guarantee a surplus every day and you have a surplus every day. Anyone claiming we need days worth of storage is inherently making an argument that days worth of storage is cheaper than simply building more generation and generation is really cheap while batteries aren’t.

We can get hard numbers on the storage required using this simulation/optimization site:

https://model.energy/

I often point to this, but it's such a fun and useful site I'll do it again.

What you get is typically (it depends on where you are) producing steady output from solar + wind requires some hours of batteries (typically much less than a day) and usually a fairly large backup of hydrogen (particularly far from the equator). The hydrogen gets burned in combined cycle plants with a mediocre round trip efficiency; most of the stored energy goes through batteries and back again at high round trip efficiency.

So, yes, one does need days worth of storage, but it's not batteries, it's a rainy day hydrogen account where storage capacity is very cheap.

Re: Will we ever get fusion power?

#283

Post by pfdietz »

tonyarkles wrote: post #138
rgmerk wrote: post #137

Earlier quoted context omitted.

Corollary: energy is going to much more expensive the further you get away from the equator (in the absence of very predictable winds/lots of hydro/cheap geothermal).

Yup… we’re probably building nuke plants. We are also building wind and solar. And some new natural gas plants. We don’t really have a whole lot left to tap for hydro, don’t really have good geography for pumped hydro storage, and while there is a pilot project on the go to try to generate electricity from mediocre geothermal we definitely don’t have good geothermal potential either. But… we sure grow a lot of food!…

No, we'll build lots of wind, and also smooth long term imbalances with hydrogen.

Heavy industry will tend to migrate to sunnier areas.

Re: Will we ever get fusion power?

#284

Post by pfdietz »

XorNot wrote: post #210
Animats wrote: post #83

Earlier quoted context omitted.

It's detailed, but dated. Most of the graphs stop between 2000 and 2005. Yet the article is from 2024. Somebody took the easy way out and copied and pasted old graphs, probably. Whatever happened to Lockheed's compact fusion program?[1] [1] https://www.lockheedmartin.com/en-us/products/compact-fusion...

Cancelled in sometime before 2021: https://aviationweek.com/defense-space/aircraft-propulsion/s... My long run prediction is that ITER will work and everything people on HN kept insisting would work in 5 years will suffer a similar fate. I'll stake my claim now that I think Helion is probably not going anywhere (just a vibe, but there's something off about their recent big marketing push).

ITER will "work" in the sense of achieving its goals, but that will all ultimately be pointless, as it's a dead end. A device with a volumetric power density 400x lower than a PWR cannot conceivably lead to a competitive energy source.

Re: Will we ever get fusion power?

#285

Post by pfdietz »

tuatoru wrote: post #268
vincvinc wrote: post #203

Earlier quoted context omitted.

Would be relevant criticism but here’s fusion startups skipping the “boiling water” step - see Helion Energy (Sam Altman funded)

On paper.

This is why I call them the "least dubious" fusion effort. Sure, things have to break right for them to succeed, but at least they have a chance, unlike tokamaks.

Re: Will we ever get fusion power?

#286

Post by pfdietz »

notTooFarGone wrote: post #175
deburo wrote: post #66

Earlier quoted context omitted.

There's a huge surge of investment into Nuclear these last few years. Innovation is starting again in that sector, I wouldn't bet against it.

So replacing old infrastructure is now an investment? There are just many reactors EoL and I'd say replacing those is not a sign that nuclear is booming right now. The future is wind/solar/battery on cost alone.

> So replacing old infrastructure is now an investment?

Yes? What did you think it was, chopped liver?

Re: Will we ever get fusion power?

#287

Post by pfdietz »

Qwertious wrote: post #185
m463 wrote: post #149

Earlier quoted context omitted.

> They'll have unlimited energy based on ...probably mining the center of the earth after finding it is methane or similar like thomas gold theorized, something like jupiter.

The centre of the earth is iron, it's how compasses work.

Note that this is not because the iron there is ferromagnetic (iron loses its ferromagnetism at its Curie temperature, which is far below the temperature of the Earth's core) but because the iron there is liquid, and convection in the core, interacting with magnetic fields, induces electrical currents that generate the field, the "geodynamo". This process is highly nonlinear and not well understood.

Re: Will we ever get fusion power?

#288

Post by pfdietz »

choilive wrote: post #250
Someone wrote: post #152

Earlier quoted context omitted.

> You get about 40% more power/area in space vs on the ground. You need about ~22 TW to "power" humanity. So you need about 70,000 km^2 of space […]. So lets round it to 100,000 km^2. But thats a significantly smaller area than the terrestrial equivalent of about 500,000 km^2. Those number are inconsistent with each other. Seems you calculated with 400% more power/area in space vs on the ground. That seems incorrect…

Ground based solar has a capacity factor of about ~25% depending on location, while a space based installation would have nearly a 100% capacity factor. So to generate the same amount of energy per year you need about 4x as many panels on the ground. I probably should not have said power but instead something like exajoules/year.

Another important issue is that in space, PV can be extremely thin. The actual active layer of semiconductor can be maybe 50 microns (for silicon) or less than 1 micron (for CdTe). This also suggests solar-powered electric propulsion in space can have high acceleration, limited by heat dissipation in the engine.

Re: Will we ever get fusion power?

#289

Post by pfdietz »

BirAdam wrote: post #127
ffgjgf1 wrote: post #49

Earlier quoted context omitted.

Well… over 80 million of people live in Germany: https://www.iea.org/data-and-statistics/charts/monthly-gener... Over-provisioning by 7x might not be extremely practical. I guess there is a lot of space in Spain that could be filled with solar panels (production only falls by ~50% there in winter so it’s not to bad) but there is certainly not enough grid capacity to transfer all of that north (and building new infras…

Personally, that lack of space is a thing that bothers me. Screw the plants and animals, we need solar farms, right?

PV produces much more value per hectare than farming does, so you're even more against agriculture, right?
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