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Comment Re:Microwaving power to Earth from space (Score 3, Informative) 111

... microwave ovens work because they're tuned to the resonant frequency of water ...

Bzzt. Microwave ovens use 2.4GHz because there's an ISM band there. There is no resonance at 2.4 GHz for water. If there was your food would explode in the oven.

Comment Why plastic balls? (Score 2) 234

Why not use a thin layer of biodegradable oil as has been proposed to weaken hurricanes? That would prevent evaporation and cost a lot less, I'd imagine. I doubt the oil would cause problems since the water is likely drained from below the surface. The only downside is the possible damage to wildlife.

Comment Re:Oh boy, here we go... (Score 1) 413

> I haven't worked in the nuclear industry either but at least I have engineering experience.

I'm not gonna complain, but I'd like to point out that just having 'engineering experience' doesn't make you an expert either.

> Nuclear tech is expensive. LFTR is probably going to be extra expensive. The economics of power generation do not favor nuclear power.

> Once-thru fuel cycles are the most cost-efficient.

> Prove to me that a LFTR design that meets regulations for nuclear safety is going to be cheaper than a comparable PWR.

Sometimes cost isn't the most important issue. Safety should be, and I think you'll agree that even the most recent PWR/BWR reactors have much more intrinsic safety in their designs than the old-school PWRs that have been running for 40+ years.

Look at solar power (something that I'm not really a fan of) - it used to be heinously expensive, but thru research into cell design and improvements in manufacturing, it's really come down in cost to where it's actually cost-effective in some situations.

> Once-thru fuel cycles are the most cost-efficient.

Yes, given that the waste is sitting, unprotected, in casks on-site. That's like an old-school coal power plant operator saying coal ash is cheap to dispose of - let's just blast it all over the surrounding counties. If you don't have to pay to dispose of it properly, then of course it's cheap.

> Deep geological storage is the safest way of dealing with waste.

No one has any idea where or how much building a facility to deal with all that wasted fuel will cost, and exactly how well it'll stay in containment for 10k years. The real answer to the waste issue is to not generate it in the first place, and what you do generate should have the actinides burned away to limit the half-lives to less than 1,000 years or so.

> No known material has been demonstrated to be capable of containing the LFTR salt over the long time periods required.

Again, I'm not wed to LFTRs or even MSR's - I'd be just as happy with a gaseous primary coolant. I want a strong negative void coefficient and other intrinsic safety features instead of the way we have it now. I want the physics to work for us, not against us.

It sounds like you and I are on the same page with regard to nuclear power - it's important, and needs to be a part of the solution. I say let's take the time and spend the money to start fresh and look at ideas that may have been discarded before but now may make sense. Let's also revamp the NRC - it's so caught up in regulatory capture with PWRs that it can't even begin to assess the safety of any other design.

Comment Re:Oh boy, here we go... (Score 1) 413

"Everything I know about nuclear power, I learned from watching LFTR videos."

That's disingenuous - I've been following the nuclear power saga since the 70's. I majored in physics (ended up w/ a minor) and I've also been inside the control room and containment vessel of an actual commercial PWR and toured a couple of research swimming pool reactors.

LFTRs just happen to be the latest 'new old' idea that's been brought back to the fore. LFTRs may not be the wave of the future, and that's ok with me, but at least someone, somewhere is thinking out-of-the-box and is concerned about the viability of nuclear power beyond our rather over-complicated existing PWR's.

Once-thru fuel cycles, one-off designs, and using a high pressure phase changing primary coolant is just silly. We need to graduate to more sophisticated and more intrinsically safe designs. We don't still use carburetors in (most) cars - fuel injection is more efficient and cleaner. We don't use turbojet-only engines on jet aircraft, we use turbofans - again, much more efficient and cleaner. Nuclear power needs to have its own renaissance, preferably sooner than later.

You'd still need a huge containment building for your LFTR. Worse, it would need to contain not just the reactor core, but the fuel reprocessing system. It would probably be bigger, not smaller, than a PWR reactor building of equivalent power.

I'm not concerned with the physical size of the building, I'm concerned with keeping the 3000 PSI corrosive genie in the bottle. A building capable of withstanding a jet impact is a lot easier to build than one that also has to contain a flash-to-steam event.

Comment Re:It's nice to have ideals (Score 1) 466

The startup time of a large motor is just a couple of seconds, and as Figure 1 in this PDF shows, a typical breaker is made to withstand 6-20x its rated current for 3 seconds.

IIRC the start capacitor doesn't store charge to help with startup current; rather it provides a phase shift in the aux winding to get the armature moving.

Comment Re:Oh boy, here we go... (Score 1) 413

Thorium solves none of the problems we have with current fission reactors.
I'm not even sure where to start - here's just one example.

If you watch the videos re: LFTRs, you'll see that most of the design of a conventional reactor is there to deal with the possibility of a primary coolant pressure loss and the resultant massive steam release. This is an enormous risk in all existing power plants. A LFTR runs at essentially atmospheric pressure and with no phase change, so there's no need for a massive high pressure containment vessel.

Comment Re: Oh boy, here we go... (Score 1) 413

Here's my local power company's tariff. Under GS-2 non-demand billing, it looks like you'd pay 8.173 cents/kWh in the summer and 7.452 cents/kWh in the winter including all charges for generation, distribution, and transmission. There's a $21.17 monthly charge, so your 4000 kWh use case would be $348.09 in the summer and $319.25 in the winter here in the Old Dominion.

Demand billing gets you $342.71 summer, $285.19 winter.

I didn't do the math for Schedule 10, but that might be even cheaper.

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