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Why are nuclear power construction costs so high? Part III – the nuclear navy

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Re: Why are nuclear power construction costs so high? Part III – the nuclear navy

#151

Post by pfdietz »

dickholesalad wrote: post #114
whearyou wrote: post #63

Earlier quoted context omitted.

Fail safe means that in a catastrophic failure of the reactor’s regulatory systems it stops functioning rather than overloads. Entropy trends it to not working rather than working too much - for example a gas furnace will stop burning if the systems running the furnace stop working and are unable to provide more gas to the burn chamber. Is that how Navy reactors work?

Chernobyl used a neutron moderator with a positive temperature coefficient of reactivity (liquid sodium), while U.S. Navy reactors use water, which has a negative coefficient of reactivity. The more energy you put into the water surrounding the reactor, the less reactive it allows the reactor to be. This has a stabilizing effect on the system. U.S. Navy reactors are inherently stable and inherently safe. To answer yo…

Chernobyl did not use liquid sodium. It was a graphite moderated thermal spectrum reactor with water as the coolant.

Re: Why are nuclear power construction costs so high? Part III – the nuclear navy

#152

Post by ncmncm »

acidburnNSA wrote: post #146
aidenn0 wrote: post #68

Earlier quoted context omitted.

One comment on your sustainability argument, now that I know you are the author: Calculating "years of energy" based off of current usage seems silly to me given that global energy usage has been rising exponentially for centuries. For example, if you assume a 3% per-year increase in global energy usage, 12 billion years becomes a bit less than 1000 years.

Today we use about 600 exajoules of primary energy per year. The sun hits us with about 3.8 million exajoules per year. 1.03^1000 is a factor of 7e12. So under that assumption, the earth would be making 1 billion times more power than we receive from the sun. I can pretty much guarantee that we won't be scaling at 3%/yr for the next 1000 years. And if we do, that's an argument for lots more nuclear fission, and a lot…

Earth? Who said any of that will be used on Earth? OK, Earth will use a bit of it.

We will need to dismantle gas giants' moons for construction materials.

Re: Why are nuclear power construction costs so high? Part III – the nuclear navy

#153

Post by acidburnNSA »

robmsmt wrote: post #122
acidburnNSA wrote: post #7

I wrote a similar take here on the topic: https://whatisnuclear.com/economics.html

Thanks for the link, what are your thoughts on the position that France is in with a number of reactors out of action and requiring repairs? From an outsiders perspective, I am curious if it is really as simple as the French not keeping up with maintenance and it catching them at a bad time or are there issues with the reactor type or other influencing factors.

They're experiencing the flip side of the argument of picking one standard reactor and building lots of them identically. If an issue is identified, it can affect your whole fleet. In this case, they were doing an inspection and found unexpected corrosion in a safety system. They checked another similar reactor and found it too. The more they started checking the more they found. So they have to go down for extended outages and repairs, as necessary. This is very bad timing, considering the gas-driven energy crunch.

The repairs can be done, and the reactors will come back online, it just takes time. Very unfortunate, to say the least.

Re: Why are nuclear power construction costs so high? Part III – the nuclear navy

#154

Post by pfdietz »

coryrc wrote: post #130
epistasis wrote: post #42

Earlier quoted context omitted.

Putting aside the wisdom of such massive defense spending, the question is what is the alternate good that could perform the job? If we spend $12B on a 1GW reactor, we have far far better alternatives. A 1GW nuclear reactor has a 90% capacity factor of undispatchable, hard to throttle electricity. At today's prices, thay $12B could instead buy 6GW of solar at 20% capacity factor, and 24GWh of batteries. This combined…

> At today's prices, thay $12B could instead buy 6GW of solar at 20% capacity factor, and 24GWh of batteries. I don't think that can actually be done. The world's largest battery installation is less than 1 GWh AFAICT. OTOH we're not doing great at nuclear either.

It doesn't have to all be one giant stack of batteries. Your argument is like saying that we can't add more than (say) 2 GW of nuclear, because that's the size of the largest nuclear power plant.

Re: Why are nuclear power construction costs so high? Part III – the nuclear navy

#155

Post by AtlasBarfed »

ncmncm wrote: post #115
xupybd wrote: post #80

Earlier quoted context omitted.

Nuclear runs constantly. Solar and wind don't. This is a significant problem. Storage is hard and inefficient. We don't currently have a viable complete renewable solution. Nuclear is much better for the planet than fossil fuels and is the only option to bridge the gap required to operate the current renewables.

Storage is not, in fact, hard. Its efficiency is not important beyond a few hours' worth, because it is rarely needed. For those few hours, battery efficiency is very good.

And even where storage is hard, things are developing FAST.

EVs are still at, what, 1% of cars on the road, and only a small percentage of dozens of transport modes by air, land, sea, from single person motorcycles to busses or even container ships.

Grid storage still basically is an "EV batteries on land". This is going to change as well.

WHich is funny because the fundamental issue any nuclear plant has to deal with isn't the current price of alternative energy + grid storage. The REAL problem is that in ten years when the thing comes online, what will the price of alternatives be then given the cost improvement curves of the last decade?

I would hazard a guess that alt energy will be half of natural gas turbine by then (and natural gas turbine is already untouchably cheaper than nuclear), and probably 2/3 the cost with functional grid storage.

I believe home solar will be cheaper than grid natural gas turbine in 10 years too. And that's without carbon taxes.

Re: Why are nuclear power construction costs so high? Part III – the nuclear navy

#156

Post by AtlasBarfed »

ncmncm wrote: post #133
xupybd wrote: post #121

Earlier quoted context omitted.

If it was rarely needed and only needed for a few hours we wouldn't need all the fossil fuel based generation to fill the gaps. I'm not aware of any significant battery based storage system deployed at scale that solves this problem. There are some large battery banks but none even close to the scale required. It's a hard problem as it would require a huge increase in global manufacturing. I'd like to be wrong here.…

It would be stupid to spend money building out storage before there is renewable generating capacity to charge it from. So, they spend on that, first. Most of the storage, in the end, will not be batteries. Most existing storage is pumped hydro, because the dams were already there. There are lots of alternatives: underground or underwater compressed air, liquified air, underground hydrogen, tanked ammonia, buoyancy,…

"Hydrogen synthesis efficiency is now well over 90%"

From what source? Hydrocarbons?

Re: Why are nuclear power construction costs so high? Part III – the nuclear navy

#157

Post by pfdietz »

aaaaaaaaaaab wrote: post #14
ok_dad wrote: post #5

Earlier quoted context omitted.

That only solves part of the problem, the civilian reactors are still too expensive to build. Nuclear is great, I went through the Naval Nuclear Power Program several decades ago myself, but it's not financially viable . Let me say that again to those engineers who weren't listening: Nuclear (fission) power is not, and will never be, financially viable for civilian powerplants. I'll eat a roll of toilet paper covered…

>I'll eat a roll of toilet paper covered in hot sauce if someday nuclear fission is financially viable enough to produce power for civilians at a decent scale. So all the world’s nuclear power plants operate at a loss? That’s a pretty strong proposition…

There's never been a single merchant nuclear plant built to sell into a competitive market, anywhere in the world. So, all the nuclear plants around were built with a captive audience of customers who were to be forced to pay for them. In the US, the remainder of nuclear interest was down in the southeast where this sort of thing still exists.

Re: Why are nuclear power construction costs so high? Part III – the nuclear navy

#158

Post by pfdietz »

donmaq wrote: post #90
epistasis wrote: post #4

Earlier quoted context omitted.

Is our ultimate goal to get nuclear at any cost? Then sure. But nuclear at any cost is not a reasonable goal. The only reason we want nuclear is for its carbon-free energy. At which point it must be evaluated on its merits, not as an end goal of its own

And how can we just ignore the waste problem? [1] In many cases, containment pools are full to the brim with spent rods [2], which is both environmentally hazardous, & a target for terrorists (dirty bombs) 1: https://www.ucsusa.org/resources/nuclear-waste 2: https://ips-dc.org/spent_nuclear_fuel_pools_in_the_us_reduci...

We can ignore the waste problem because nuclear fails even if we do so.

Re: Why are nuclear power construction costs so high? Part III – the nuclear navy

#159

Post by AtlasBarfed »

xupybd wrote: post #95
donmaq wrote: post #87

Earlier quoted context omitted.

> Nuclear is much better for the planet than fossil fuels and is the only option to bridge the gap required to operate the current renewables. That's a strong declaration without any solution in sight for nuclear power-generated waste: https://www.ucsusa.org/resources/nuclear-waste

There are pragmatic solutions for the limited but long lasting deadly waste created. https://world-nuclear.org/information-library/nuclear-fuel-c...

Well the best strategy would be LFTR/MSRs that can breed and/or burn the waste to usable isotopes or as fuel. But it's always interesting how much pro-nuclear people are anti-MSR or anti-anything-but-huge-concrete-domes-and-solid-rods

Because the lobbies underlying nuclear power in solid fuel rod processing is a lucrative government boondoggle.

All the nuke proponents say "we are losing all the old guard!". I actually think this is a feature, nuclear needs to be reformulated and reassessed from the ground up without all the political and military biases, and once they have stable cost profiles in wind/solar to actually target.

If they can actually make a competitive reactor once wind/solar stabilizes, likely at 1/2 to 1/3 the current real dollar cost.

Re: Why are nuclear power construction costs so high? Part III – the nuclear navy

#160

Post by megaman821 »

ncmncm wrote: post #148
pclmulqdq wrote: post #129

Earlier quoted context omitted.

So what is supposed to replace all of these obsolete technologies that currently account for the vast majority of energy generation? Lithium batteries, solar power, and offshore wind power? There are so many problems with this scheme, not least of which is that you have pretty much no base load and batteries can't be manufactured at anywhere near enough scale to successfully do this "transition" for at least the next…

Most storage will not be batteries, unless a new battery chemistry proves radically cheaper (which might happen). Right now the overwhelming majority of storage is pumped hydro, almost as dispatchable as batteries. There are plenty of alternatives.

Grid scale batteries are in their infancy. There are over 100 different technologies in the oven now. The technology, mining, refinement, and manufacturing will mature. In 20 years nothing will come close to storing energy at the price and scale of grid batteries.
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