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chickenbig

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intentional Polonium 210 from decay chains

What do you mean "decay chains"? Po-210 decays to Pb-206 which is stable. So you mean Po-210 decay. Let's shut down the chemical industry because someone attempted to poison The Skripals. https://en.wikipedia.org/wiki/Poisoning_of_Sergei_and_Yulia_... .

medical mistakes

Spent nuclear fuel is generally not used for medical isotopes. They specially prepare samples for irradiation to not have to use reprocessing, e.g. https://en.wikipedia.org/wiki/Cobalt-60#Production .

I could have a look for you

It would be illuminating to see what you find reasonable.

It is a complex answer, and heavily depends on decay product chemistry.

The source you provided does not agree with that assessment. It is purely radiation damage. The Pu-238 (half life 87.7 years) and Pu-239 (half-life 24,110 years) experiments.

    plutonium-induced health effects are considered to be the result of energy deposited by alpha particle emissions in tissues that retain plutonium for extended periods (i.e., lung, bone, liver following inhalation exposure). Similar health effects would be expected from any alpha-emitting source that would result in similar cumulative tissue-specific radiation dose and dose rate.
They seem fairly certain that it is alpha particle damage, not chemistry.

The "high level waste" is the stuff that takes 10k years to decay.

Well, there are many definitions, for instance https://ukinventory.nda.gov.uk/information-hub/factsheets/wh... is from the UK.

The big things that you get out of reprocessing nuclear fuel

You generally extract the trans-uranics from fission products. The former needs more specific treatment to deal with their longer half lives (or turning into MOX, which ends up more expensive than using normal uranium). The latter get vitrified (who needs the Sr or Cs, really).

The things we might use (plutonium, strontium) have some rather "questionable" applications:

The Pu-238 for the RTG is generally produced in trace quantities in reactors, with reactor grade plutonium containing mostly Pu-239 and Pu-240.

I'm not a huge fan of these tiny RTG sources either. Spacecraft yes, otherwise ... proven to be somewhat dangerous when they become orphaned.

if something is radioactive enough to be a hazard then it's radioactive enough to generate power

Only under certain circumstances is it financially worth harnessing this power. I think of space probes and their RTGs. They use alpha emitters like Pu-238, to minimize the shielding requirements.

As for the rest of the stuff, dry casks are good enough. Reprocessing isn’t currently economical while uranium is so cheap, although the vitrification of the fission products can help immobilize the worst radiation emitters, but really the UO2 structure does a decent job of keeping things put.

three other major events

What is the measure of major? The INES scale? https://en.wikipedia.org/wiki/International_Nuclear_and_Radi...

Sarov in 1997

One person died in the criticality accident in a weapons research lab.

Mayak Production Association in 2017 ... it was a huge release

https://inis.iaea.org/records/ndb3s-s5507 "In some regions, over 100 mBq/m³ were measured as one-day means. Although resulting exposure was far below radiological concern"

the Nyonoksa explosion

Nuclear powered cruise missile.

we might as well count Hanaford

https://madihilly.substack.com/p/hanford-what-a-waste

Prismatic (or cylindrical) TRISO also makes sense. There are lots of potential problems using pebble beds (circulation, grinding), whereas doing regular refuelling cycles avoids them, in exchange for down-time to refuel.

almost as much engineering , plumbing, safety mechanism, personnel, maintenance, etc

Sure, that is economics, not thermodynamics. I don't necessarily agree with the SMR manifesto, but it is conceivable that improved financing, construction, operation and oversight could make an SMR cheaper than a larger reactor.

then neither the Russian invasion of Ukraine nor Hormuz blockade would have been a huge deal. The cost of energy is destroying your industrial base.

Domestic heating has little to do with industrial base. Fertilizer prices would still have risen. Grain supplies would still be affected.

One was eventually built after massive delays and cost overruns.

Areva underbid on the fixed price contract to win against the ABWR, IIRC. Admittedly the Fins were not pleased at the time overrun, but the construction cost was historically not so bad given it was FOAK in a country without recent construction experience .

There is nothing wrong with over provisioning cheap renewable power generation when it is economically superior to building fossil assets that will end up stranded.

Solar cannibalises solar, so the price when the sun shines may tend to zero, but that does not ensure the price to the consumer of the electricity they need tends to zero, or even lower than it was.

stockpiles and ammunition or other non-reusable military gear are basically the definition of money 'destroyed'

Goods like longer-lasting food, medical supplies or a strategic oil reserve are not wasted. The money that went into supplying them has gone back into the economy, and they serve a more strategic purpose than the market participants could have borne (i.e. societal insurance policies). The same could also be said of military stockpiles, and continuing to buy them sustains a capability that is hard to get back once lost.

The article quotes £147/MWh for CCGTs. These look to come from the Electricity Generation Costs 2025 [0] released on the same day as the CfD results. However there is no £147/MWh in Annex A [1]. There is a £145/MWh for CCGT delivered in 2030, but the way this was arrived at is interesting.

a) A load factor of 30% (which seems pretty low for a CCGT), that is actually ~28% (per Annex A [1] "Technical Costs and Assumptions" sheet);

b) fuel efficiency is set to be 54%, which is far lower than BAT CCGT of around 64%, which affects fuel and CO2 emissions costs;

c) the analysis missed out capacity market payments that one gets for having dispatchable power stations;

d) the analysis presumes £41/MWh of carbon costs.

The key drivers of the price are load factor (so amortised construction costs), conversion efficiency (fuel costs and carbon costs) and carbon costs themselves. These make up 90% of the LCOE.

[0] https://www.gov.uk/government/publications/electricity-gener... [1] https://assets.publishing.service.gov.uk/media/6967b0c806fab...

Heating from gas is quite peaky (morning and evening heating cycles), whereas heat pumps are best when run low-and-steady.

Assuming 2/3 of residential heat demand transitions to heat pumps, and assuming an optimistic COP of 3 in the worst weather (highest flow temperatures, lowest air temperatures ... perhaps more like 2.5), then the power required to heat this fraction of houses is 2/3 / 3 = 2/9 of the mean gas demand. [0] linked report figure 1 shows a (smoothed by eyeball) demand of around 140GW "local gas demand" during the Beast from the East. This implies heat pumps would take over 31GW to power, which is more like 60% of the current UK electricity supply.

[0] https://ukerc.ac.uk/publications/local-gas-demand-vs-electri...