Thread

1. preisschild · 1790751984 · focus · HN ↗

   The BWRX-300 footprint is so large they might as well just build large nuclear power units again and get 3-4x the power

   1. nine_k · 1790754444 · focus · HN ↗

      I don't think that the footprint is the key factor. Likely the total construction cost is. A large reactor may have a better cost per kWh, averaged over decades of its lifetime, but a smaller reactor likely has a more affordable upfront cost.

      1. jillesvangurp · 1790762848 · focus · HN ↗

         The key point with small modular reactors vs. reactors like this is that construction happens in factories rather than on site. Theoretically, you might get some economies of scale from series production in a factory that is much harder to get doing bespoke construction projects. Which is why historically, nuclear projects tend to blow through their cost estimates and why having larger reactors makes that a bit more tolerable. Of course until somebody actually does this and scales to hundreds/thousands of reactors production, this is all theoretical.

         This particular reactor is already estimated at over 5 billion $ I think. That's a lot of money for just 300MW and it probably could end up being a wildly optimistic estimate as well. I think effectively much of the construction is still on site and not in a factory. Hence the need for a construction permit. So, you get all of the downsides of complex on site construction such as including high cost, permitting overhead, lots of bureaucracy, associated delays & uncertainty, etc. without the upside of actually delivering a lot of power like you would with a larger reaction. Calling it "modular" might be overstating things a bit.

         Probably cheaper, faster, and easier to just plonk down 5GW of solar, wind, or battery (or combinations of those). Especially if you calculate in the 200-300% time and dollar budget that many nuclear projects seem to end up having. Maybe this one will be different. A lot of people have a lot riding on Nuclear projects breaking this trend. But then that has been the case for decades.

         1. mrngld · 1790769989 · focus · HN ↗

            If the argument is, in part, about footprint then enough solar and battery capacity to output 300MW around the clock with the same uptime/reliability as a nuclear plant is surely going to cover a lot more ground.

            I only bring that up because footprint was a point further up the thread.

            There's still a fair amount of site work that has to happen here in the small modular concept, but I think when parts of it happen continuously in a factory you're largely immune from a lot of the jobsite nonsense that happened from contractors milking the job for every dollar they could get, plus economies of scale that you do get in a factory setting (citation: industrial revolution).

            1. myrmidon · 1790772482 · focus · HN ↗

               Nuclear reactor uptime is gonna be 90% at most, which is rather easy (battery capacity for several days) to beat even with just solar + batteries (in equatorial and most mid-latitude regions, at least).

               1. roryirvine · 1790780965 · focus · HN ↗

                  And this BWRX design is based on ABWR which turned out to be only 70% in practice.

                  You don't get much useful notice for unplanned nuclear outages either, whereas both wind and solar output can be forecast with reasonable accuracy 24h in advance.

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