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Westinghouse AP300 Small Module Reactor

westinghousenuclear.com

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Re: Westinghouse AP300 Small Module Reactor

#11

Post by mandevil »

BMc2020 wrote: post #5
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 (…

Didn't the PRC buy 4 AP1000s and then start building their own knockoff? (not pirated so much as that was one of their demands and Westinghouse accepted)?

Anything bigger than 1600MW, Westinghouse doesn't get a licensing fee for it getting built. So they are building 1600MW size right now.

Re: Westinghouse AP300 Small Module Reactor

#12

Post by jay_kyburz »

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…

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.

Re: Westinghouse AP300 Small Module Reactor

#13

Post by nomel »

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?

Re: Westinghouse AP300 Small Module Reactor

#14

Post by jandrese »

jay_kyburz wrote: post #12
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…

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.

Re: Westinghouse AP300 Small Module Reactor

#15

Post by jandrese »

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?

Mostly it is the half lives of the reaction products, sometimes the half lives of the decay products or intermediate products. Ramping up and down was historically somewhat difficult, famously one of the contributing factors to the Chernobyl accident was the reactor having been turned down to a very low level on the previous day. You have to be careful not to accidentally poison your reactor during the day when the solar farms are chugging out megawatts only to not be able to ramp up in the evening when the sun sets.

Re: Westinghouse AP300 Small Module Reactor

#16

Post by credit_guy »

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 decreases. If for some reason the reactor stops producing enough heat, the water cools down and more fission starts happening. And there are other negative feedback processes in place too, for example Doppler broadening [1].

This is great for safety, but not so great for load following. If you want to load follow, it's probably going to be many times cheaper to just invest in a bunch of batteries.

[1] https://en.wikipedia.org/wiki/Doppler_broadening#Application...

Re: Westinghouse AP300 Small Module Reactor

#17

Post by credit_guy »

daydream wrote: post #10

Have they sold any of these to anyone yet?

Of course not, they have to get first the approval from the Nuclear Regulatory Commission. They estimate this would take 3 years. I don't find that unrealistic, since it's based on an existing (i.e. approved) reactor design, AP1000. NuScale got their approval last year, and they applied in December 2016 [1]. So about 6 years for a design submitted by a new company with no prior experience whatsoever.

[1] https://www.nrc.gov/reactors/new-reactors/smr/licensing-acti...

Re: Westinghouse AP300 Small Module Reactor

#18

Post by rgmerk »

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.

To be fair, in a lot of cases you'd probably build multiple units on the same site which would get you some learning effects. But compared to wind, solar, and batteries...

Re: Westinghouse AP300 Small Module Reactor

#20

Post by nrp »

jay_kyburz wrote: post #12
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…

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.

I believe that is how KEPCO operates on the reactors they build outside of Korea.
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