SMRs are hitting strong headwinds

[woodgeek]

One issue here is throttleability. Gas plays well with solar+wind because it can throttle, and just gets hurt by reduced capacity factor slowing amortization. But the capital cost is low and the fuel cost is a significant part of the operating cost.

Nuclear is high capital, low fuel cost and throttles poorly if at all. So if it doen't throttle, some of its power is sold cheap and either way its amortization gets killed.

And then batteries (charged by RE) put a ceiling on power prices when the sun is down... and you have no business model.

I agree that national security is always a concern, but in a future with copious SWB power, and larger periods of excess production, its not clear what we need for deep backup. It could be some fossil plants on standby that get used a couple times a year.

 

[EbS-P]

One issue here is throttleability. Gas plays well with solar+wind because it can throttle, and just gets hurt by reduced capacity factor slowing amortization. But the capital cost is low and the fuel cost is a significant part of the operating cost.

Nuclear is high capital, low fuel cost and throttles poorly if at all. So if it doen't throttle, some of its power is sold cheap and either way its amortization gets killed.

And then batteries (charged by RE) put a ceiling on power prices when the sun is down... and you have no business model.

I agree that national security is always a concern, but in a future with copious SWB power, and larger periods of excess production, it’s not clear what we need for deep backup. It could be some fossil plants on standby that get used a couple times a year.

I agree the economics just are not there. It’s about time to shelve these SMRs. If they were 20-30 years earlier they may have had a shot.

 

[DBoon]

Nuclear is high capital, low fuel cost and throttles poorly if at all.

I recall reading that some of the SMR designs throttle over a fairly wide range - presumably a big advantage for them if they can be made cost-effectively.

 

[woodgeek]

I recall reading that some of the SMR designs throttle over a fairly wide range - presumably a big advantage for them if they can be made cost-effectively.

Cool. Over what time span? Might not be the best word choice on my part. I'm thinking more like 'dispatchable'.

And I don't think reactors like that (they were doing deep throttle/dispatch tests on Chernobyl when, you know).

 

[peakbagger]

I think nuclear works in an economy like Russia or China where they have large tracts of uninhabited land where waste can be dumped cheaply or in the case of nuclear subs, just taken out in deep water and sunk. A lot more difficult in a representative democracy where folks are going to object to having it dumped in their backyard. When the government did the "deep dive" for suitable geological formations in the US, they reportedly found many but they were all taken out of the running for other reasons. The other aspect is the criteria for most of these sites is "forever". Folks forget that humankind in general is just a blink in geological time, or for those in the northern US , every 12 to 15 thousand year, there is major cool down of the earth that forms glaciers that cover a big chunk of the earth and scrape every bit of top soil and a fair share of the topography down to bare rock, last time it happened the terminal moraine at the edge of the glaciers in New England was south of Boston. Right not the earth is still in an interglacial period that is getting long in the tooth. A little bit of radioactive waste will be the least of societies problems, if they make it that far.

 

[DBoon]

Over what time span?

On the X-Energy website, the FAQ at the bottom has their answer (and yes, I do realize that there is no real-world operational proof, so take this claim as the marketing that it is). And while this wouldn't be called dispatchable, it does have some claimed ability to do something other than just supply a baseline load. Other SMRs may make similar claims.

Does the Xe-100 reactor support load following?
​

Yes, the Xe-100 has load-following capabilities, and is designed to ramp up or ramp down between 40% and full power in 12 minutes, faster than what is achievable by existing Generation III nuclear technologies.
The Xe-100 has a versatile design that can be applied to several end markets, as well as to conventional power generation.