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Westinghouse AP300 Small Module Reactor

westinghousenuclear.com

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Re: Westinghouse AP300 Small Module Reactor

#71

Post by pbmonster »

booi wrote: post #61
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.

Is it actually cheaper and easier? Seawater isn’t exactly known for its ease of use and non-corrosiveness and fouling is a real problem. Not to mention all the sea life that isn’t going to respond well to high temp water spewing out..

> Not to mention all the sea life that isn’t going to respond well to high temp water spewing out..

Ideally, you're not dumping the hot water back into the harbor. At least from a naive theory perspective, you could put huge cooling towers on deck and cool the reactor 100% through evaporative cooling. Bonus: the huge steam/mist cloud out of the cooling tower could help delay global warming through marine cloud brightening [0]. Whether the deck of a floating reactor has enough space and stability to support cooling towers of the appropriate size is a question for the engineers.

That's how most reactors in first world countries with temperate climates work anyway. Because it really messes up the biosphere of your river/coast, if you just dump 3GWh of thermal power straight into the water.

[0] https://en.wikipedia.org/wiki/Marine_cloud_brightening

Re: Westinghouse AP300 Small Module Reactor

#72

Post by wkat4242 »

elihu wrote: post #55
acidburnNSA wrote: post #33

Earlier quoted context omitted.

The best way to solve this problem is to build a huge shipyard-based reactor-making gigafactory that makes floating gigawatt scale reactors that are floated to location. You can operate them offshore or on land. This was actually attempted in the 1970s by Offshore Power Systems (joint venture between Westinghouse and Newport News). They bought and installed the world's largest gantry crane on Blount Island in Jackson…

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.

Re: Westinghouse AP300 Small Module Reactor

#73

Post by YakBizzarro »

scythe wrote: post #30
derefr wrote: post #28

Question about SMRs generally: does the fact that random private companies can apply to buy one of these, mean that nuclear reactors are now basically "state-secret free" as a technology? Or are there still state secrets, but they're all in the e.g. uranium enrichment part of the pipeline — that buying one of these gets you no closer to seeing — rather than in the reactor design?

Building a nuclear warhead requires assembling a large sphere (ish) of material well above critical mass faster than it can explode. Only then does the chain reaction efficiently consume a lot of fuel before it breaks up (inertial confinement). Usually, you need to use explosives to blast the different pieces of fuel into each other. This requires very accurate control of the explosions that ignite the warhead, and i…

well, not really. the fuel in typical reactor is lowly enriched uranium (LEU), meaning that only a small percentage of the fuel is actually fissile (ie. it breaks when interacting with one neutron and release energy). So no, it can't get sustain an exponentially growing reaction chain in any condition, since neutrons are absorbed by the non-fissile part of the fuel

Re: Westinghouse AP300 Small Module Reactor

#74

Post by simonh »

rgmerk wrote: post #6

Some history might be worth going in to here. The AP1000 design was an evolution of an earlier design called the AP600. The AP600 conceptual design apparently didn't find any customers because the economics of it were unappealing compared to larger reactors. In a nutshell, if you're going to build a huge containment building etc etc etc, it doesn't cost (in theory) that much more to go even bigger and get more power…

The problem is they are constrained by the needs of the one customer they definitely have, the US Navy. It's their need for reactor power plants for their nuclear submarines and aircraft carriers that is funding the development of these systems and setting the basic requirements. The commercial market is an afterthought.

Re: Westinghouse AP300 Small Module Reactor

#75

Post by przemo_li »

pbmonster wrote: post #71
booi wrote: post #61

Earlier quoted context omitted.

Is it actually cheaper and easier? Seawater isn’t exactly known for its ease of use and non-corrosiveness and fouling is a real problem. Not to mention all the sea life that isn’t going to respond well to high temp water spewing out..

> Not to mention all the sea life that isn’t going to respond well to high temp water spewing out.. Ideally, you're not dumping the hot water back into the harbor. At least from a naive theory perspective, you could put huge cooling towers on deck and cool the reactor 100% through evaporative cooling. Bonus: the huge steam/mist cloud out of the cooling tower could help delay global warming through marine cloud bright…

That's too native. Output is indeed cooled but only enough to be only fraction hotter then input. Then dumping is safe again.

This is also why most of those power plants have to shut down. It's not the physical lack of water, but instead input is already so hot that output would already be over the upper limit.

Nobody build enough cooling towers to cool with them "needlessly".

Which is also why global warming is disastrous to energy sector. Those older power plants just don't have enough cooling capacity for newer higher temperatures.

Re: Westinghouse AP300 Small Module Reactor

#76

Post by cinntaile »

acidburnNSA wrote: post #33
rgmerk wrote: post #6

Some history might be worth going in to here. The AP1000 design was an evolution of an earlier design called the AP600. The AP600 conceptual design apparently didn't find any customers because the economics of it were unappealing compared to larger reactors. In a nutshell, if you're going to build a huge containment building etc etc etc, it doesn't cost (in theory) that much more to go even bigger and get more power…

The best way to solve this problem is to build a huge shipyard-based reactor-making gigafactory that makes floating gigawatt scale reactors that are floated to location. You can operate them offshore or on land. This was actually attempted in the 1970s by Offshore Power Systems (joint venture between Westinghouse and Newport News). They bought and installed the world's largest gantry crane on Blount Island in Jackson…

Why did no one buy a floating reactor?

Re: Westinghouse AP300 Small Module Reactor

#77

Post by u320 »

timerol wrote: post #3

These are pretty big SMRs - 300 MWe, compared to 77MWe from NuScale. Definitely an iteration of reduced size from their 1 GWe model, as opposed to a "as small as reasonable" design. It's cool that they call out 15 MWe / min "load following" capability. Ramping up and down in response to renewables will be an important function of any nuclear reactor installed today.

The so far most successful SMR, BWRX-300, is also that size, and also a scaled down version of a long lineage of reactors. They are shooting for the same price target as well. So they are just going where the market is going.

Re: Westinghouse AP300 Small Module Reactor

#78

Post by zo1 »

Mistletoe wrote: post #47
aeontech wrote: post #43

Earlier quoted context omitted.

That is incredible! If this project actually went into production, we would be living in a very different world right now...

People always say this, but if it was so great wouldn’t someone have bought some? The money never seems to work out.

I doubt it was the money that killed this. Probably regulatory and environmental concerns. Imagine the headlines and phrasing of news articles.

Instead we got this crap that is a floating barge of environmental ruin:

https://karpowership.com/en/global-presence

Notice how it's only been installed in 3rd world countries.

Re: Westinghouse AP300 Small Module Reactor

#79

Post by natmaka »

epistasis wrote: post #49
dirtsoc wrote: post #37

Earlier quoted context omitted.

What's sad is that it's mainly the US that has problems with this. China has managed to bring multiple of this reactor design to fruition while the US still screws around with building just two. I live in Georgia and the almost decade of overruns and corruption are being about to be paid for by Georgia Power customers via rate hikes.

France and Finland have had excessive difficulty with their EPR. My hypothesis is that modern economies with high wages will simply not be able to build a nuclear reactor economically. It appears to require a certain amount of 20th century technological advancement, but not so much economic advancement that labor costs are too high. France had a much better track record with nuclear in their first round of building.…

The first EPR project in France (Flamanville-3) had problems documented in an official report (dubbed 'Folz', per the name of its main author), sadly AFAIK it wasn't translated into English: https://www.economie.gouv.fr/rapport-epr-flamanville

A piece about it: https://www.archyde.com/the-folz-report-draws-up-a-severe-as...

This study may also offer some hints: https://www.sciencedirect.com/science/article/pii/S030142151...

Re: Westinghouse AP300 Small Module Reactor

#80

Post by Ekaros »

nomel wrote: post #13
timerol wrote: post #3

These are pretty big SMRs - 300 MWe, compared to 77MWe from NuScale. Definitely an iteration of reduced size from their 1 GWe model, as opposed to a "as small as reasonable" design. It's cool that they call out 15 MWe / min "load following" capability. Ramping up and down in response to renewables will be an important function of any nuclear reactor installed today.

> 15 MWe / min "load following" capability I know nothing of nuclear. What sets this rate? Is it some system level thermal gradient limitation? Or maybe the complexity of the safety around the movement?

Part of it is also that whole system have large amount of "inertia". We are talking about megawatts of power. First in heated water and then passed through a massive turbine. This whole process carries for a bit. And you want it to run the grid and not the other way around.
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