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Westinghouse AP300 Small Module Reactor

westinghousenuclear.com

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Re: Westinghouse AP300 Small Module Reactor

#21

Post by pfdietz »

epistasis wrote: post #7
nukeman wrote: post #2

Seriously? I’m insanely pro-nuke, and work in the nuclear sector, but Westinghouse should really focus on their AP1000. They’ve already got deals in place with several countries, and now that they’ve got them running in more than one country, there might be a chance of bringing costs down some. The light water SMR market is getting crowded rather fast. They’re competing with both GE (and their BWRX-300) and NuScale (…

Given the track record of AP1000 construction, who do you think would ever order one? I don't see a future for this. If somebody thought it was a feasible design for construction in Western countries, they could buy the half completed sites at Summer for a song. I also think 300MW is too big. It's not really small enough to get the supposed benefits of small and modular. The entire nuclear industry appears to be off…

The whole industry, and its fan base, has descended into overt magical thinking. It is sad, and not a little ridiculous.

Re: Westinghouse AP300 Small Module Reactor

#22

Post by innrautha »

credit_guy wrote: post #16
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.

> Ramping up and down in response to renewables will be an important function of any nuclear reactor installed today. Realistically, it's not going to happen. PWRs are inherently stable, that's one of their big selling points. If anything goes wrong and the reactor becomes too hot, the water expands, moderates less the neutrons and they don't slow down enough to trigger fission events, so the rate of fission decrease…

That depends on what they mean by load following. While you can load-follow by changing reactor power (like the French do extensively). Westinghouse has long been promoting thermal storage based load following in their other reactor designs [1]. Where instead of perturbing the reactor's power, you divert the thermal output to a molten salt thermal battery when you want to decrease power suddenly, and use the battery to pre-heat feedwater when you want to increase power suddenly. For their LFR design they are claiming they should be able to load follow within 65-125% of nominal full power (ramping at 10%/minute). As long as the load-following averages out to 100% power over a long/short enough time period the reactor never has to change power level.

The only really needed to do this at any thermal plant is to over size the steam turbines, install some piping, and build an insulated salt tank.

Of course Westinghouse hasn't built any plants with that feature since it doesn't make economic sense without variable energy pricing.

[1] "Status Report – Westinghouse Lead Fast Reactor," (Westinghouse Electric Company LLC, United States of America), https://aris.iaea.org/PDF/W-LFR_2020.pdf

Re: Westinghouse AP300 Small Module Reactor

#23

Post by pfdietz »

credit_guy wrote: post #16
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.

> Ramping up and down in response to renewables will be an important function of any nuclear reactor installed today. Realistically, it's not going to happen. PWRs are inherently stable, that's one of their big selling points. If anything goes wrong and the reactor becomes too hot, the water expands, moderates less the neutrons and they don't slow down enough to trigger fission events, so the rate of fission decrease…

And if you're going with batteries, you might as well charge them with a source that has low levelized cost. That's not nuclear.

Re: Westinghouse AP300 Small Module Reactor

#24

Post by m4rtink »

epistasis wrote: post #7
nukeman wrote: post #2

Seriously? I’m insanely pro-nuke, and work in the nuclear sector, but Westinghouse should really focus on their AP1000. They’ve already got deals in place with several countries, and now that they’ve got them running in more than one country, there might be a chance of bringing costs down some. The light water SMR market is getting crowded rather fast. They’re competing with both GE (and their BWRX-300) and NuScale (…

Given the track record of AP1000 construction, who do you think would ever order one? I don't see a future for this. If somebody thought it was a feasible design for construction in Western countries, they could buy the half completed sites at Summer for a song. I also think 300MW is too big. It's not really small enough to get the supposed benefits of small and modular. The entire nuclear industry appears to be off…

Some older plant blocks were in the 300-500 MW range so I guess you could replace them with this ?

Re: Westinghouse AP300 Small Module Reactor

#25

Post by PaulHoule »

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…

Also the AP1000 takes a superheavy forging press which can take a few 100 tons of steel. There are just so many of those, only in certain countries (North America does poorly) and those presses can build a limited number of reaction vessels.

A smaller reaction vessel needs a smaller press which is easier to find.

Re: Westinghouse AP300 Small Module Reactor

#27

Post by prpl »

jandrese wrote: post #14
jay_kyburz wrote: post #12

Earlier quoted context omitted.

You would think it would be economical to just move the work force around with the projects. You get the talent, but built in place.

It's harder to find quality people who are willing to relocate their family every time a job is finished.

Do you know many pipe fitters?

Re: Westinghouse AP300 Small Module Reactor

#28

Post by derefr »

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?

Re: Westinghouse AP300 Small Module Reactor

#29

Post by wahern »

jandrese wrote: post #14
jay_kyburz wrote: post #12

Earlier quoted context omitted.

You would think it would be economical to just move the work force around with the projects. You get the talent, but built in place.

It's harder to find quality people who are willing to relocate their family every time a job is finished.

A large portion of the workforce which recently completed Vogtle units 3 and 4 temporarily relocated to the site from around the country. Many people lived at RV camps opportunistically setup by farmers or others with large empty lots. Especially if you had family, living out of an RV was a good way to minimize expenses and maximize how often you could afford to travel back home.

At big jobs like these, especially outside a handful of major metro areas, there will never be enough local labor. Even for "unskilled" positions, you don't want too many unproven or inexperienced people as they're likely to cause trouble, such as hurting themselves or others, or not consistently showing up on time--schedules can be both grueling and erratic, and many people can't hack it.

Re: Westinghouse AP300 Small Module Reactor

#30

Post by scythe »

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 is where the secrets are.

A nuclear reactor uses fuel juuuust barely above critical mass so the reaction is slow. It's a very different thing. Producing the fuel is just basic centrifuge isotope separation, which has many non-fission applications.

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