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Energy

blog.samaltman.com

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261–270 of 287 posts

Re: Energy

#261

Post by pjc50 »

XorNot wrote: post #212
icanhackit wrote: post #159

Earlier quoted context omitted.

think of finance in terms of latency/bandwidth [...] reactors are high latency - they're expensive and take a long time to set up I like this metaphor. I think what you might have implied but didn't explicitly mention was distributed vs centralized when thinking about these systems as well. Solar can be a distributed system whereas fission & fusion systems are centralized. Even though you can make small fission syste…

Faults are not a serious issue with a fusion reactor beyond it breaking down. Neither is waste - an inert reactor is harmless unless you insist on crowbaring into the core to bathe in all those activated inner wall materials.

crowbaring into the core

This is all Freeman's fault, isn't it.

Re: Energy

#262

Post by pjc50 »

jddw wrote: post #201
flgb wrote: post #140

Earlier quoted context omitted.

I suspect they will continue to trounce fission and fusion for a long time, at least until there is some some technical innovation in transmission and distribution. Transmission and distributed generation accounts for half the cost of electricity. The question for our electricity future is distributed versus centralized generation, and distributed will probably win.

So distribute fission and fusion, overcomes much of that. And distributed solar and wind needs backup which is usually fairly centralized. Unless you want to spend 3-5 times as much for your energy to buy batteries.

Fusion needs to be distributed well away from population centres. Until we've had enough contained failures of the "intrinsically safe" reactors to be convinced that it's actually true.

Re: Energy

#263

Post by dharma1 »

There already is a very well working fusion reactor - the sun - and it's free. We just need better battery tech.

Re: Energy

#264

Post by pjc50 »

kitd wrote: post #243
slyall wrote: post #153

Earlier quoted context omitted.

Pumped storage is hard to scale down and has a fairly fixed loss. There are a bunch of other storage technologies that are at the "almost there" stage though. I personally like the Pumped Heat storage from Isentropic as a possible mainstream contender: http://www.isentropic.co.uk/

That looks really interesting, though I wonder about the energy losses in the pumping mechanism. Are pistons particularly efficient? As an added bonus, they're based just down the road from me!

Piston efficiency is basically limited by leakage round the seals and friction on the bearings. Can be in the very high 90%s. The system efficiency is limited by Carnot cycle like everything else, I think; they are claiming 75% AC-AC round trip, which is impressive if true.

Re: Energy

#265

Post by pjc50 »

mikeash wrote: post #57
chinathrow wrote: post #47

Earlier quoted context omitted.

It's not paranoia, it's a real issue with that waste. We have no working waste solution as of today. We have no working long term storage solution as of today. We have not priced the cost of long term storage/plant decomissioning etc at the full cost into the price of nuclear power - that is for most countries. https://en.wikipedia.org/wiki/Asse_II_mine http://www.spiegel.de/international/germany/dealing-with-ass...

What's wrong with copying the solution used for all the other toxic waste modern industry produces? We have no working long term solution for storing arsenic, but people mostly seem fine with "just dispose of it in a way where it doesn't leech into the groundwater" and not the crazy restrictions everyone wants to put on nuclear waste storage.

Chemical waste tends to stay in the container. Nuclear waste tends to fire gamma radiation and the occasional neutron through the container.

Re: Energy

#266

Post by MrBunny »

Why are we so focused on having only one solution for energy? I would understand the cost would decrease when you put all your eggs in one basket but can we really find one type of energy source that has no disadvantages? Wouldn't we be better served with diversity of energy production (more than we have now)?

Re: Energy

#267

Post by mikeash »

mikexstudios wrote: post #195
mikeash wrote: post #38

Earlier quoted context omitted.

The half life of the immense amount of chemical toxic waste produced by industry each year is essentially infinite. And yet somehow we're mostly content with chucking it in a landfill (albeit ones regulated and built to safely handle it) and calling it good. Drop the dangerous period from "infinity" to "some millions of years" and suddenly people get more worried?

Well, the difference between chemical toxic waste is that there are accessible methods for making it non-toxic. It's just a matter of cost. For example, toxic organic and inorganic compounds can be thermally decomposed. For organics, you create elemental carbon. For inorganics (containing metal ions), you can reform the metal and collect it. Acid/base waste can be neutralized. You can't really do that for radioactive…

What about elemental toxins like mercury and arsenic?

Re: Energy

#268

Post by beat »

donttrustatoms wrote: post #131
beat wrote: post #84

Earlier quoted context omitted.

So how small a reactor? And what sort of cost, what sort of setup time, what sort of safety constraints (ie, current reactors are generally water-cooled and need access to large bodies of water)? It's possible to trim the cost of reactors from the billions to the millions, maybe, but how many millions? Certainly, solar with batteries is a lot more expensive - but to my point, startup cost is low. Latency, or bandwidt…

You're exactly right, and that's what we designed for with UPower. I would have written the exact same thing when we began talking about doing something in nuclear 5 years ago. Too many reactors are designed without the market or financing in mind. We decided on the simplest possible reactor optimized to a size useful to a market in dire need- just MW scale. It has no pumps, no water in the reactor, and builds upon a…

It's exciting work, to be sure. Before now, the only small-scale nuclear work I'd seen were plutonium batteries (like for powering satellites), which are horrendously expensive and not something you ever want in the hands of Bad Actors.

It looks like UPower is currently targeting environments where traditional power is impractical and lots of power is needed, and plenty of budget is available - remote mines, military installations and such. Do you see a market for urban/residential power grid in the future, too? Or would that be too difficult a squeeze between distributed solar and traditional power plants?

Re: Energy

#269

Post by beat »

XorNot wrote: post #212
icanhackit wrote: post #159

Earlier quoted context omitted.

think of finance in terms of latency/bandwidth [...] reactors are high latency - they're expensive and take a long time to set up I like this metaphor. I think what you might have implied but didn't explicitly mention was distributed vs centralized when thinking about these systems as well. Solar can be a distributed system whereas fission & fusion systems are centralized. Even though you can make small fission syste…

Faults are not a serious issue with a fusion reactor beyond it breaking down. Neither is waste - an inert reactor is harmless unless you insist on crowbaring into the core to bathe in all those activated inner wall materials.

Faults are not a serious issue with a fusion reactor, because energy-positive, sustaining fusion reactors don't exist.

Yet.

I'd love to see this change, but I'm not gambling humanity's future on the assumption that this is a solvable problem.

Re: Energy

#270

Post by mikeash »

pjc50 wrote: post #265
mikeash wrote: post #57

Earlier quoted context omitted.

What's wrong with copying the solution used for all the other toxic waste modern industry produces? We have no working long term solution for storing arsenic, but people mostly seem fine with "just dispose of it in a way where it doesn't leech into the groundwater" and not the crazy restrictions everyone wants to put on nuclear waste storage.

Chemical waste tends to stay in the container. Nuclear waste tends to fire gamma radiation and the occasional neutron through the container.

When you store the stuff, you add shielding for the radiation too.
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