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Westinghouse AP300 Small Module Reactor

westinghousenuclear.com

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Re: Westinghouse AP300 Small Module Reactor

#121

Post by epistasis »

sofixa wrote: post #111
Gwypaas wrote: post #110

Earlier quoted context omitted.

Hinkley Point C, started 12 years later, is going swimmingly I hear! Going to cost the consumers ~$150/MWh and it is starting to look likely that EDF even at that incredibly high price takes a loss on it. > Since construction began in March 2017, the project has been subject to several delays, including some caused by the COVID-19 pandemic,[10] and this has resulted in significant budget overruns. As of May 2022, the…

Started before all problems had been fixed with Flamanville and Olkiluoto, it's a part of the initial generation.

Do you have any examples of a very high cost reactor dropping by a significant amount on a subsequent build?

South Korea was able to eke our small decreases in cost (though some people have ended up in jail for falsifying record keeping). But otherwise, costs tend to rise. And I'm definitely not aware of a drop of 50% or so, to bring these excessive costs into the realm of competitiveness.

Re: Westinghouse AP300 Small Module Reactor

#122

Post by pfdietz »

mindslight wrote: post #108
pfdietz wrote: post #106

Earlier quoted context omitted.

Combustion turbines operate at a much higher temperature (as much as 1300 C) than a nuclear reactor, especially a LWR (about 325 C), so the exhaust temperature can be much higher. Also, a turbine is much cheaper: a simple cycle combustion turbine is maybe $500/kW(e), vs. perhaps 20x that for a NPP. The reason a combustion turbine can be so hot is that the heat is produced in the working fluid itself, by a chemical re…

But if the main thing they want is low temperature process heat, then the specific method of generating electricity shouldn't actually matter? NPPs also produce electricity plus lower temperature 'waste' heat. Unless the waste heat put out by the NPP is too low temperature to be used for process heat? Or the real advantage is that the refineries ramped up their electricity generation (turning waste fractions into ele…

Direct use of nuclear heat had nothing to do with PURPA. PURPA wouldn't have made it more likely to be considered, since it wasn't putting power onto the grid. If nuclear wasn't being used for industrial heat before that, it wouldn't suddenly have become reasonable afterwards. Instead, PURPA would have made that less likely, since it would have improved the economics of the competing technology of burning fuels for process heat (since a valuable and saleable additional product, power at very high marginal efficiency, could now be produced and sold to the grid.)

There is the question of why nuclear had not and has not penetrated the market for industrial heat. I suspect it has something to do with nuclear not scaling down well, not being suited to industrial applications that may require more flexibility, and concerns about nuclear requirements bleeding over into design and operation of otherwise non-nuclear industrial processes.

Where will process heat come from in the future? Possibly heat pumps. The thermal energy from these (or from resistive heaters, at high temperature) is much cheaper to store, per unit of energy, than electrical energy in batteries, so this would provide a large, cheap source of dispatchable demand to ease renewable integration.

Re: Westinghouse AP300 Small Module Reactor

#123

Post by Animats »

pfdietz wrote: post #86
evilos wrote: post #81

Earlier quoted context omitted.

Which SMRs don't have a full scale containment vessel?

None, although I think some (NuScale?) save money by sharing pressurized containment volume among multiple reactors. Just hope you don't see multiple correlated meltdowns. Containment vessels could also be made smaller if steam filtering were used instead of planning to just contain and condense it. I don't know if any SMRs plan to do this.

NuScale's containment vessel is a metal cylinder around the reactor.[1] Each reactor has its own containment vessel. It's just slightly larger than the reactor, like Fukushima and Peach Bottom. Here's a good drawing.[2] No user-serviceable parts inside. The building is not a containment.

[1] https://www.nrc.gov/docs/ML1535/ML15355A411.pdf

[2] https://spectrum.ieee.org/media-library/image.jpg?id=2557419...

Re: Westinghouse AP300 Small Module Reactor

#124

Post by epistasis »

sofixa wrote: post #114
Gwypaas wrote: post #112

Earlier quoted context omitted.

Is not the definition of insanity is doing the same thing over and over and expecting different results?

When building complex infrastructure for the second/third/etc. time? Of course not. Economies of scale is the term you're looking for.

When has nuclear ever had economies of scale?

Re: Westinghouse AP300 Small Module Reactor

#125

Post by elihu »

pyrale wrote: post #91
elihu wrote: post #55

Earlier quoted context omitted.

A side benefit of being on or near the ocean is immediate access to a thermal sink. Nuclear power plants (and also fossil fuel thermal plants) divert substantial amounts of water for cooling. If fresh water is increasingly in short supply around the world, that's a problem. The usefulness of the ocean as a thermal sink though depends on water temperature which can vary a lot depending on where you are.

> The usefulness of the ocean as a thermal sink though depends on water temperature which can vary a lot depending on where you are. No. The difference between pumping water at 15°c or 30°c is negligible when you're cooling water at 325°c. You may have to pump a tiny bit more water, but that's a non-problem when you have an ocean.

Fair enough.

Re: Westinghouse AP300 Small Module Reactor

#126

Post by elzbardico »

wkat4242 wrote: post #72
elihu wrote: post #55

Earlier quoted context omitted.

A side benefit of being on or near the ocean is immediate access to a thermal sink. Nuclear power plants (and also fossil fuel thermal plants) divert substantial amounts of water for cooling. If fresh water is increasingly in short supply around the world, that's a problem. The usefulness of the ocean as a thermal sink though depends on water temperature which can vary a lot depending on where you are.

Yes this caused major issues in France this year, the surface water was so warm it was not ecologically sound to use it for cooling so some nuclear plants had to shut down or throttle.

This was vastly exaggerated probably to distraction the attention from the French public that the vast majority of the plants being put offline was due to the fact that they had their maintenance postponed till the limits, and then you had a bunch of reactors that, per regulations, needed to be turned-off at the same time. Only a few of the plants had this thermal problem, the ones that discharge hot water directly into the rivers.

Re: Westinghouse AP300 Small Module Reactor

#127

Post by botanical »

tibbydudeza wrote: post #69

We could use it here in South Africa. The bulk of our power comes from coal fired plants but due to the low quality coal for cost reasons and thus high sulphur and lack of preventative maintenance it results in boiler tube leaks nearly every week. Some of our plants are at the end of their lives and their replacements are no better off due to corruption and a malady of technically incompetent builders (looking at you…

We'd need 23 of them. Depending on the cost, it would be better than nothing. Currently, I think it costs R10 mil to generate 1MW through solar; so R70 billion with solar.

Re: Westinghouse AP300 Small Module Reactor

#128

Post by killjoywashere »

pyrale wrote: post #93
killjoywashere wrote: post #68

Earlier quoted context omitted.

Nuclear subs and carriers operate in salt water all the time. It's "just" chemistry

Nuclear subs and carriers produce a fraction of the power of a commercial nuclear power plant.

I'm not sure why that matters? Salt water is salt water. An carrier's brake horsepower is ~200MW, so a fraction, but a reasonable fraction. When San Diego had a county-wide power outage in 2011, the carriers at North Island pushed power to the grid to support essential services.

Re: Westinghouse AP300 Small Module Reactor

#129

Post by geraldhh »

derefr wrote: post #45
acidburnNSA wrote: post #35

Earlier quoted context omitted.

All power reactors are free of state secrets and owned by private institutions. Some information is required by law to remain secret, such as locations of security hardening features, cameras, guns, etc. Good old Eisenhower and Atoms for Peace, 1953.

> Some information is required by law to remain secret, such as locations of security hardening features, cameras, guns, etc. This was more what I was trying to motion toward — if you sell a power reactor to the private market, aren't you basically guaranteeing that "locations of security hardening features" and so forth will be able to be scrutinized at leisure by foreign state actors who can then use that informati…

true, this information will also be available to everyone in short time, but i don't think it's a big problem.

secrecy is a sliding scale, and delaying and thinning out access to this information makes it "more secure" but surely some cleaning person will tell their buddies over a pint.

Re: Westinghouse AP300 Small Module Reactor

#130

Post by Certhas »

pyrale wrote: post #116
Gwypaas wrote: post #109

Earlier quoted context omitted.

Assume a capacity factor of 50% then to handle peak loads? Now the nuclear costs $240-440/MWh. That is ridiculous costs, worse than Europe during the last winters Russian war induced gas crisis. https://www.lazard.com/research-insights/levelized-cost-of-e...

It's hard to give numbers for 100% nuclear since no one does that, but yes, France has load factors between 60 and 80% depending on the reactor type. https://www.iaea.org/fr/newscenter/news/contribution-du-nucl... The report you quote already cites load factor around 90% for new builds, a 50% load factor wouldn't double the costs. That being said, 90% load factor for a grid with a high share of nuclear is probably ex…

Once you electrify your heat demand seasonal variability will massively increase, driving down load factors dramatically.

Today electricity accounts for 20% of energy use, European estimates see that going up to 50% by 2050. A large chunk of that increase is heating.

Obviously other countries and climates will not see the same patterns here.

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