NuScale

The small modular reactor, tendered December 2016 and submitted the next month (h/t Green). It's now got Fed approval.

One (infamous) holdup in nuclear power is getting the plants insured. It's Pascal's Wager: the risk is deemed up to a Chernobyl level, effectively infinite. You know and I know that we don't run RBMK in burgerstan, but we do have analogous problems: corner-cuts, politics, denialism. I am not the first blogger to draw parallels with the contemporary Challenger disaster. No insurer can dish out for a Vladimir Ilyich Lenin Nuclear Power Plant #4. So, insurers don't, and the government does.

"But pebble-bed", we've been saying for decades. Well sure - in theory. But there's the paradox: there's the new stuff which is safer in theory, and the old stuff which although historically flawed is at least known.

And then: Jurassic Park. What if some gamma-male on staff deliberately sabotages the works. I expect this is why the labs' management is going so nuts - they must appease the loudest constituency, and to whatever ideology they must mentally enslave the staff. Spinning off that point, insurers are in this same #woke boat. If Prudential (say) insure some plant that some greenie got xir eye on, they're getting #cancelled. "What if they go bankrupt", the whispers will whisper. Now they cannot insure anything else.

NuScale got an answer: diminish the scale of the reaction. Power-generation at 50 MW per module, in a 23x5m long cylinder; twelve (12) modules. The failsafe is handled through gravity: if the AZ-5 button is pushed, the motors stop and the control-rods just fall down.

NuScale say they can scale the design up to 60 MW / mod. ArsTechnica don't inform if that's from added fuel or from energy-capture. I hope the latter but suspect the former. Insurance will cost more for more fuel.

This design should protect insurers so to allow a private market in insurance... for the end-user. Also to be insured will be production and distribution of the isotope, which NuScale tell us is uranium: probably U-235 but conceivably U-233 ("Thorium") [UPDATE 2/28/21 which besides being breedable from a common metal, itself has a lower critical-mass so can scale the whole thing down even further]. I strongly suggest laws that the supply-chain have different insurers than those involved in the reactors on-site. Although given the Proliferation worries, the producer at least will be Uncle Sam.

These reactors will, I suspect, go out to constituencies without a strong NIMBY movement. Cheap land, low population, downscale labour-pool of that. I could see the first reactors going, ironically, into West Virginia where the coal mines will use them to mine more coal. This stands to drive down the price of coal as to make that competitive with natural-gas again. I'm afraid we'll need to stick coal with more regulations.

And who else wants reliable 50 MW off the power-grid: server-farms, I am sure. Stick 'em in the Washington / Oregon outback.

Of course this reactor should work as well for Venus' 8.7-.9 gravity as for Earth's 9.8 - failsafe will take a fraction of a second longer to drop. It won't work in space (although the inner-planet shell don't care, they got photovoltaics). Unsure about underground Mars or our Moon.

UPDATE 10/27/21: A competitor.