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by njarboe 663 days ago
We started to access nuclear power as a new source, but then stopped for quite a while. It looks like things are starting up again. We'll see.
1 comments

the issue with nuclear power is that the humans don't yet have the technology to exploit it economically; at their current primitive level it's uncompetitive with other sources of energy. like printing 1000 years ago or heron's aeolipile
> humans don't yet have the technology to exploit it economically

$2,500/kW of capacity isn't too expensive, given the alternatives.

https://www.latitudemedia.com/news/catalyst-the-cost-of-nucl...

The recent batch of 11 reactors authorised by China are perhaps 2.8B USD each for 1.1GW plant (plus a high temperature gas reactor).

but 1.1 gigawatts of mainstream solar panels is 0.14 billion usd. $130 per kilowatt of capacity. even at the dismal 10% solar capacity factor achieved in very northerly countries like germany, the reactor is twice the price per average watt, and it needs to be installed far from the point of use—you can't buy a 440-watt nuclear reactor, so you need transmission, distribution, and transformers, all of which incur energy losses, capital investment, and safety hazards you can avoid with photovoltaic

that large grid also needs regulation, billing, and political stability. (a reactor is an appealing target for both russian glide bombs and enron-style scams.) and the reactor is not dispatchable over timescales of less than a day, while you can short out a solar panel in microseconds

fundamentally the reactor can't compete economically because it's shackled to a pricey steam engine. the reactor itself is a triviality, just a pile of fuel larger than the critical mass. some of them formed naturally at oklo billions of years ago. what's hard is integrating that energy release mechanism into a machine, and that's because the humans are still terrible at making machines

> but 1.1 gigawatts of mainstream solar panels is 0.14 billion usd

A solar farm is more than just solar panels. This 3.5GW solar farm cost 2.13B USD, so by your estimates the panels make up just 1/5 of the cost of the farm. I'd expect the load factor of the nuclear power station to offset the solar farm's nameplate capacity advantage, and lead to steadier prices/fewer storage requirements etc etc.

https://www.pv-magazine.com/2024/06/06/worlds-largest-solar-...

> and it needs to be installed far from the point of use

Note that this is a problem for solar farms in China; they are installed where land is not valuable. Hence all the HVDC transmission records being broken in China. Plus nuclear power stations can be close to populations. For instance https://en.wikipedia.org/wiki/Daya_Bay_Nuclear_Power_Plant is 50km from Hong Kong.

> the reactor is not dispatchable over timescales of less than a day

Modern reactors have load following capabilities, e.g. the AP1000 can ramp up 5% a minute within the 15%-100% band.

Pure PV farms have minimal operational costs, nuclear has huge ongoing costs. For a more realistic comparison the operating costs of nuclear offset the cost of batteries for solar.

So capital costs vs capital costs on a per Wh basis isn’t in favor of Solar it favors nuclear which has less flexibility. IE: 24 GWh per day of battery backed solar can dump half that power over 2 hours @ 6GW. 24GWh of nuclear IE a 1GWh reactor caps out at 1GW. If you want to ramp to 6GW of output nuclear needs several nuclear reactors and all of their associated costs.

> Modern reactors have load following capabilities

Load following isn’t free for nuclear, any time you’re not operating at 100% you’re losing money. Batteries are inherently way more flexible.

It also costs more to build a load following reactor and they have more experience maintenance issue due to thermal stress. Nuclear inherently favors steady state operations due to the Xe pit (https://en.wikipedia.org/wiki/Iodine_pit) but it also requires being taken offline for long periods for maintaining, refurbishing, and or refueling.

> Pure PV farms have minimal operational costs, nuclear has huge ongoing costs.

https://www.iea.org/reports/projected-costs-of-generating-el... page 59 table 3.13a puts O&M for nuclear in the USA at about 12 USD/MWh plus just over 9 USD/MWh for fuel, and table 3.14 puts O&M for utility scale solar at around 6 USD/MWh or so.

As for batteries, I think a few hundred USD/kWh is a reasonable guesstimate of cost (raw LiFePO4 cells are now sub-100 USD/kWh). Backing up each hour of production of a 1GW power station would cost a few hundred million USD, plus the cost of the solar farm to charge the battery up.

> 24 GWh per day of battery backed solar can dump half that power over 2 hours @ 6GW

At which point the transmission becomes the limitation; the grid operator probably wants a fairly stable flow of electricity through the wires to maximise utilisation so the 6GW is not realistic, nor would moving the electricity during the day to load-adjacent storage be efficient.

> Load following isn’t free for nuclear, any time you’re not operating at 100% you’re losing money.

I was responding to the point that solar panels are inherently more flexible because you can turn them off (because ...????). The same reasoning you've made about nuclear load following being uneconomical can be made about pure solar too.

> Nuclear inherently favors steady state operations due to the Xe pit

Operators change the boron concentration to offset the negative change in reactivity due to Xe-135 levels. For PWRs this is not a big problem, you just have to know it is there and do the calculation for I/Xe concentrations given the power levels.

i agree that the difference in capacity factor is very important, and i should have made that clearer in my comment. nuclear is typically around 85%, solar typically around 20%. solar farms in the california desert are 29%, so this desert plant might have a similarly high capacity factor, but last time i checked, the prc average was more like 10%, and i don't understand why. possibly factors like transmission congestion are to blame and will be at play here too

especially if it's cheaper to put up more solar panels somewhere more overcast than to build hvdc transmission lines from urumqi to shanghai

it turns out that, if you use solar panels the same way you'd use nuclear reactors, by centralizing them hundreds or thousands of kilometers away from where the energy is used (as in this case), or by concreting over prime beachfront property (which nuclear power plants need) to build giant solar farms on, they can cost almost as much as nuclear reactors do, or even more

this is analogous to how factories first used electric motors: they installed a giant electric motor in the factory's powerhouse to drive the line shafts, replacing the steam-engine the powerhouse was built for. consequently electrification famously didn't increase factory productivity for decades

when i said that nuclear power plants 'need to be installed far from the point of use', i didn't mean that they couldn't be tens of kilometers, or even single-digit kilometers, from the point of use. i meant that they can't be single-digit meters from the point of use. solar panels can, and that dramatically drops costs

i appreciate the correction about the ap1000! naval nuclear reactors have been able to rapidly ramp up and down since forever, so it's good to see that capability making it into commercial nuclear power

> i meant that they can't be single-digit meters from the point of use. solar panels can, and that dramatically drops costs

Transmission costs, yes. Plus if the solar is behind-the-meter you might avoid some of the taxes and levies applied to grid electricity.

(Note that I realise the focus of my comment from here on down has changed from China to the UK, but then again I've not helped install a solar installation over there!)

However with UK rooftop solar home-owners do not have much negotiating power as the market supply is restricted by the MCS scheme (Microgeneration Certification Scheme). This may be changing in the future (Flexi-Orb scheme), but until a greater pool of competent installers are in the market the prices will not decrease.

A relative had 6.4kW solar (and 5kW hybrid inverter) installed last summer for around £7,000. I added in some batteries for another few thousand. The panels generated around 5,100 kWh last year, for a capacity factor of around 9%.

One larger cost you might think of with solar is land - but even in the U.K. where land isn’t exactly cheap leasing prices are about £1k an acre per year, and an acre will generate about 350MWh a year, so that’s well under 1 cent per kWh, so it’s lost in the noise.

https://www.fwi.co.uk/business/alternative-land-uses-leasing...

where land cost comes in is that it forces you to put solar generation far away from energy consumption, which incurs transmission and distribution costs which can be several times larger than the cost of the generation itself, as documented elsewhere in this thread for urumqi

as an example, a 100-megawatt electric arc furnace might occupy 1000 square meters, and it's amenable to solar's intermittent energy supply in a way that blast furnaces aren't, but even at the ideal kilowatt per square meter, it needs 100 000 square meters of solar panels to power it, about ten city blocks. more plausibly it needs several times that. you can't physically fit those panels closer than hundreds of meters from the arc furnace, and land costs mean you probably have to put them out in the countryside, likely tens of kilometers away

Yea and that 0.3c/kWh land cost is in the UK which is a terrible fit for nuclear.
Ops, make that “fit for solar