The frontrunners in the trillion-dollar race for limitless fusion power | Hacker News Reader

The frontrunners in the trillion-dollar race for limitless fusion power

fastcompany.com

10 pointsclouddrover14 comments

Serious work on commercial fusion began 70 years ago. Ever since, it's been "about 20 years away". And - who says it'll be limitless? (I know, it'll also be safe, clean, and too cheap to meter.)

So say I give you an unlimited source of 100 million C plasma that is producing energy and spewing neutrons eveywhere.

What then? How do you make a viable power station that is practical to make in a timely manner and requires little to run compared to solar with some form of storage?

And that's ignore that you'd be dumping so much heat keeping it fusing that it'd do what we do today with a blanket of CO2 but directly.

I'd stick a bit of plasma in the boiler of every coal plant on earth.

Before that, I'd short the stock of every coal mine I could.

Coal is already not competitive.

So, do short coal, but not because fusion will ever produce so much as one solitary kWh of commercially competitive energy. It will not.

And when it immediately destroys the boiler of the subcritical steam generator that already costs more to run than viable options even if fuel is free? I mean that's an upside I guess, because it gets us off coal.

There will not be "limitless fusion power".

There will not even be "limited fusion power".

What there is, in their place, is defrauding investors. There is plenty of that. (NRGV, e.g.) Such investors are supposed to be able to look after themselves, but often enough they are pension funds managing what is supposed to be people's retirement money.

In short: yes, deuterium is cheap, relative to the energy available from fusing it. Even tritium is cheap. But actually extracting that energy in usable form is extremely expensive. It is, in fact, overwhelmingly more expensive than extracting energy from fission.

And fission is not competitive. Existing fission plants will be mothballed as their output is undercut by renewables to the point where no one will pay enough for it to support continued operation.

Renewable energy is not at that point yet, but its cost is still in free fall.

If someday it turns out my reactor could have worked, I hope history will learn a lesson from my failure to give it the chance it deserved. I'm basically at the end of my rope.

It might be limitless, but Gerald O’Neil did point out that there’s only so much heat the Earth can radiate into space, global warming reduces this even more.

The main alternative would be to move a fair amount of industry into space, but even then thermal management is not trivial.

Dumping heat into the air as cooling is one of those things that’s taken for granted.

The good news is that, for the forseeable future, we can use some percentage of the generated energy to capture carbon, creating a net loss of heat.

No idea who Gerald O'Neil is, but he's absolutely wrong. The entire world consumes about 20 TW of electricity. At the same time, we receive about 200000 TW of energy from the Sun. We are in a rough balance, so we also radiate about 200000 TW. 20 TW is not even a rounding error. If we increase our electricity consumption by a factor of 100, it's still going to be a rounding error compared to how much we receive from the Sun and then radiate into space.

And 3% forcing is enough to cause cataclysm. Which gives us 100 to 200 years to get off the growth train. ie. we are exactly where we were WRT direct thermal forcing now as we were WRT GHG when the alarm first started being raised.

So when your rube goldberg plasma machine produces ten times as much heat as work then we need to end exponential growth before the transition happens rather than 50-10 years after and immediately replace it with solar. If it produces 100x as much heat as work, it's not even useful for that.

Luckily the process of extracting the energy and containing the plasma is so convoluted it's never going to be viable anyway even if the fusion step works.

Inertial confinement might result in a viable machine, but I'm not holding my breath

Use heat-pipes along the space-elevators we will have by then. Radiate away from up there.

That's so much simpler and more achievable than using a solar panel instead and not wasting orders of magntude more energy than we need. Thanks

I assume you mean Gerard O'Neill, and I don't recall him saying this. Can you cite the source?

https://en.m.wikipedia.org/wiki/Gerard_K._O%27Neill

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