Re: New fusion power system test creates 300,000 degrees C plasma

There is a fusion breakthrough about every week lately.

That's a lifestyle: announce a nanotech or web thing or goofy windmill or AI or some such breakthrough, raise a lot of money, buy a private jet, declare bankrupcy, repeat.

They don't have to worry about upsetting the neighbours.

It would be lovely to have 50kWTh or so of PU238 in the basement, if it could be made cheaply enough. Power for a lifetime for the whole house and then some.

Jeroen Belleman

That woud warm up the planet nicely. You can't turn it off.

Sounds like the "universal solvent", hard to contain.

...but the lifetime might not be very long if any got out.

Pretty negligible, I think. Assuming about 3e9 homes on this earth, it would add about 0.1% to the heat budget of the whole earth. As a side effect, it would reduce CO2 emissions by a whole lot, so the overall result may well be a drop in global average temperature.

It's *easy* to contain. It's the fools that are a problem. We have no shortage of those, unfortunately.

That is not to say it would solve all problems. Producing enough 238Pu cheaply enough would be a problem. There would be lots of red tape too. There would be hard-to-predict economic effects. I think the technical problem of designing a compact package producing 15kW or so of electricity and enough heat for hot water and space heating would be comparatively minor.

Jeroen Belleman

If, if. Such arguments can be used to prove anything.

I've got a diesel-powered car in the basement garage. Fully tanked, it contains 60kg of fuel, good for 2.4GJ or so. Imagine the havoc that could cause, if it got loose. For reference, a stick of dynamite is about 1MJ.

It can be made safe enough, I'm sure. As energy is concerned, there is no such thing as /perfectly/ safe.

Jeroen Belleman

I've seen what happened when builders accidentally set fire to a tank of diesel far bigger than that. It burned slowly and steadily until it set fire to the roof of the house - then the house burned down. Nobody was injured or killed, the mess was easily cleaned up and a new house built on the site.

It wasn't like the sudden release of energy you would get in a fuel-air explosion (quite difficult to initiate with diesel without specialist knowledge) and there wasn't a lot of residual toxic contamination.

OK. Now back to small 238Pu fuelled units. Why would you expect anything to go wrong if the Pu was contained in a hermetic canister?

Jeroen Belleman

That's too big a temptation for kids and terrorists.

Why not have local power plants make electricity and hot water, whatever way works best?

I don't understand rooftop solar cells either. Or backyard windmills. Let the utilities do what they are best at.

Remember when Mao wanted people to make steel in their backyards?

If it lost cooling, it would melt through anything. Then you'd have plutonium slag and vapor all over your garage. The neighbors might complain.

That's interesting: if you could confine some mass of 238, what would its ultimate temperature be?

The US national ignition facitility was mainly intended to work out whether nuclear bombs would go off. The nuclear fusion stuff is just done to keep the scientists happy.

Of course it would.

Terrorist can't get at them to take them apart and use the Pu-239 to make an atomic bomb.

With any luck, there won't be a WW3.

All big science projects make work for scientists and engineers. That doesn't make them worthless.

In your ever-so-expert opinion.

Of course you do. It's much too small to generate more energy than you have put into it to get the fusion to take place at all.

Being big isn't a virtue. Being big enough to do something useful is.

There's always an idiot (or a terrorist) who would challenge themself to open it.

The fact that you post the same assertion repeatedly doesn't change the fact that it is wrong.

Stars are a lot smaller that the universe, and they manage to fuse nuclei on a very large scale. We would be here if they didn't.

Thermocouples don't convert much of the heat energy available into heat.

Even a venture capitalist would have enough sense to avoid investing in you.

Perhaps they will.

This isn't a nuclear reactor! It'd be only a few tens of kilowatts, about the power level of a car engine. Those don't melt down, do they?

As for the ultimate temperature of a quantity of 238Pu, make up the balance of heat in over heat out. A fresh load releases about 560W/kg.

Jeroen Belleman

Yes, probably. There have been similar incidents in the past. I'm convinced it can be made safe enough for widespread normal use, but there will always be some fool somewhere. If we let that stop us, no technology is safe enough.

Jeroen Belleman

It has everything to do with it, but you are too dumb to see the connection.

That's the explanation you like. There are others.

It's anthropogenic global warming. If we stop digging up fossil carbon and burning it, that extra warmth will go away eventually - but it is likely to take a few centuries.

But they rely on that big fusion reactor hanging there in the middle of the solar system. It's been there for about 4.5 billion years. Nobody realised that it was nuclear fusion reactor until quite recently, and the message still doesn't seem to have got through to you.

They do when the water cooling system fails.

By "confine" I meant no heat loss. Half-life is 88 years, and there will be additional heat from decay products.

(US billions)

A kilogram, properly distributed, would make a city uninhabitable for centuries. Imagine such an active alpha emitter in a water supply.

It would make some cool glow-in-the-dark gadgets.

Critical mass is around 10 Kg. Kids could make nukes.