Lots of interesting data. It struck me as a generally proper study.
One thing that struck me as odd and not-so-proper is the allowance for accidents. Somehow the authors get a value of CO2 emissions that is more than twice as high with accidents and incidents included.
Basically they are saying accidents add 3.6 MILLION tons of CO2eq.
My question is, what are Koltun et al. smoking? Must be powerful stuff.
GT-MHR is a Gen IV reactor with extremely low core damage frequency. So that'd require that a big accident somehow emits BILLIONS of tons, if not tens or hundreds of billions of tons of CO2eq!!
But even if accidents were frequent, how could you possibly spend more energy/CO2 emissions on that than to fabricate, construct, operate and decommission the facility?
Post by engineerpoet on May 8, 2019 22:49:03 GMT 9.5
The list of accidents includes things I'd never heard of, such as the incident in Bohunice, Slovakia. It took me several searches to find what happened there. The two fatalities were not from radiation, they were from suffocation due to leakage of the CO2 coolant! The two workers did not follow safety procedures and would likely have lived if they had.
One of the claims is outright fraudulent. The "waste disposal accident" in Cadiz was nothing of the sort; it was a "cesium 137 source" (probably medical or industrial). Nothing at all to do with a power plant.
Getting to the meat of the matter on page 8, I find the treatment to be obfuscatory rather than elucidative. The "GHG emissions" from accidents and incidents is presented as a given, not analyzed... and the source is Wikipedia! (See note 22.)
Conclusion: This paper is a joke, intentional or not.
Yeah, some of those things were pretty sloppy. To be fair to the authors, it looks like they just copied the data on accidents from other references.
Still a pretty powerful table - all the "deadly" nuclear/isotope accidents in one table - and still under 100 fatalities. From a half century of global nuclear!
No other source can make those low fatality claims.
Definatly an issue with many of these papers - they throw about some acronyms about the methodology, which database they used, etc. and then say "and here's the result". Uh, pretty big steps missing there... it should be like, grab a pocket calculator and you can follow and verify our approach... but sadly it never is in these "scientific" papers.
Still I'm not too badly disposed toward the paper. Their result is still a very low lifecycle emission. It generally feels quite positive, except for some warts like the Slovakia misreference and the "accident CO2 emissions" that frankly, sound a bit too Facobson-esque to me (nuclear war CO2 emissions, anyone?). Yeah, an accident causing billions of tons of CO2, that makes sense.
Also interesting is the EROEI figure - if I calculated that correctly, amounts to 45. Pretty decent. Given that this type of reactor uses a ton of energy - low power density core, lots of energy intensive graphite, higher enrichment, energy intensive fuel form fabrication, and so on.
I just think the authors smoke some powerful dope on occasion, so these blatant errors slip in.
Post by engineerpoet on May 9, 2019 0:13:28 GMT 9.5
Heh, if you're interested in curious numbers, I calculated that it would take about 450,000 SWU to enrich reclaimed LWR uranium to make an S-PRISM startup core (1% U-235 feed, 21.29% in product, 0.2% in tails). The USA has enough used LWR fuel to make about 330 such cores from re-enriched U and reclaimed Pu and is producing more at about 8 core's worth a year.
FWIW, an S-PRISM core appears to have a gross output of about 1000 MW(t). 330 such cores would produce heat equivalent to 10% of US primary energy consumption.