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0 pointsAnthonyMouse16d ago0 comments

"Decommissioning costs" are essentially bad math. Here's this again:

https://www.ourworldofenergy.com/images/electrical-power-gen...

Nuclear, inclusive of construction costs: ~$181/MWh, only better than natural gas because no CO2. Nuclear, cost of continuing to operate an existing reactor once it's already built: $31/MWh, basically the cheapest thing on the market, half the cost of continuing to operate an existing natural gas plant (because you need so much less fuel).

What this implies is that if you build a nuclear plant you're going to want to continue operating it for 80 years, and even then you probably want to just modernize it again instead of actually decommissioning it.

The long-term average returns from ordinary investments (e.g. S&P 500) are ~10%/year, implying that even if you require decommissioning to be prefunded (unlike any competing form of power generation), the amount of money you need is less than 0.05% of what the cost will be in 80 years. Adding $500 million in decommissioning costs isn't $500M in net present costs, it's only $250 thousand in net present costs, because you take the $250k and add 80 years worth of interest (1.10^80) which multiplies your starting capital by more than a factor of 2000.

It's really just the construction, and that's in significant part because you have to build more of them to get economies of scale for building them.

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pydry16d ago

>Decommissioning costs" are essentially bad math.

This is disingenuous. Bad math is focusing on the one part of nuclear power which is relatively cheap (fuel) and ignoring the rest where the majority of the cost is, which is what you did.

I wasnt comparing nuclear power to gas anyway I was comparing it to solar and wind which produce no CO2. FIVE times cheaper LCOE.

Nuclear power needs anyway to be paired with dispatchable energy source like batteries or gas just as solar and wind do.

It isnt a competitor with gas or batteries it is a complement to gas and batteries, just like solar and wind.

AnthonyMouseOP16d ago

> Bad math is focusing on the one part of nuclear power which is relatively cheap (fuel) and ignoring the rest where the majority of the cost is, which is what you did.

The majority of the cost is construction, which is expensive when you're trying to amortize the costs of a plant design over only one or two plants instead of a hundred, which is what I said.

> FIVE times cheaper LCOE.

Five times cheaper as long as you want the most output when the market price is the lowest and the least output when it's the highest. And "five times" is with existing subsidies.

> Nuclear power needs anyway to be paired with dispatchable energy source like batteries or gas just as solar and wind do.

Nuclear power is baseload. All three of those do different things.

Suppose you have 10 GW of minimum load (e.g. late evening to sunrise) and 20 GW of peak load (e.g. late afternoon to early evening). Then nuclear is good for the former and solar+storage is good for the difference between the former and the latter.

To begin with, solar output actually partially aligns with the latter. Load is higher during the day. It's also high just after sunset, but that's only for a couple hours, and then you don't need a lot of batteries to cover it, which you can charge with more solar. But you'd need a lot more batteries (or gas plants) to make it through the whole night. That kind of sucks if load looks like it currently does, and it really sucks if you want people to switch from fossil fuels to electric heat, because then the highest load is going to be in the hours of darkness on the days with the least sunlight.

Meanwhile it's not just a problem that there is no solar output when it's dark. Sometimes renewable output is low for an extended period of time. It could be at 20% of typical for a month. Having enough batteries to last a month rather than just overnight is prohibitively expensive. So instead you'd have to build five times as much generation, which is only the same cost as nuclear because of government subsidies (which would require a much larger government budget allocation if you tried to build that much of them), and only if you're using the recent high price of nuclear that comes from building very few plants instead the lower prices that would be possible by doing it at scale.

And even using the subsidized price for renewables against the current price for nuclear, if you actually tried to build five times the capacity in renewables, the "generates the most when the market price is the lowest" thing would destroy you. The price on most days would then be zero because of huge oversupply and you'd have to recover the same total cost as current nuclear from only the days when your output is lowest.

Meanwhile if you use nuclear for what it is, i.e. baseload, and build only as much of it as you have minimum load throughout the day, it not only doesn't require any storage, it avoids the need for solar to use storage to supply power at night. Then you use solar for the incremental load during the day, to charge the batteries to use for the incremental load in the early evening and for charging electric vehicles by putting chargers in workplaces.

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