alt Hacker News> Solar panels are so cheap that you can massively overprovision for winter and still come out ahead of nuclear.
Only you don't. In latitudes that get winter, solar output is only about a quarter as much in the winter as in the summer. You often hear things like "twice as much in the warmer half of the year" to try and stuff October and March into the "colder half" and disguise how screwed you are in December and January. Worse, if you electrify heating then it's not just that solar supplies less in the winter, you also have more demand in the winter.
By this point you're not just overbuilding by a bit, you'd need five times as much or more in January as in July. "Five times as much" is already over what it costs to use nuclear. Then it gets worse, because you now have a price of zero during the summer and even the spring and fall because of the massive oversupply and lower demand, so you now have to recover the entire cost of the overbuild during the three months when you're generating the least amount of power.
Then it gets worse yet, because heating demand is higher at night and we haven't yet added the cost of storage.
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why are you ignoring wind power in this argument thread?
Okay, let’s say that we use solar + battery to cover everything but Nov, Dec, Jan, when the days are too short. Solar is cheaper than nuclear the rest of the time, so (due to the way energy markets work) we pay solar producers the cost of nuclear generation, creating strong incentive to build out more solar + battery.
So we end up using nuclear 1/4 of the time. But unfortunately, nuclear’s cost is in the capital expense, not the operating expense. We pay about the same amount for it regardless of whether we’re using it or not. So if we’re only using 1/4 the energy, the cost per watt of nuclear energy is effectively 4x larger.
This incentivizes further build-out of solar, catching those sweet winter profits (now 4x larger!), further squeezing nuclear’s usage, driving up its prices, and incentivizing even more solar.
Eventually nuclear gets squeezed out and solar’s profit margins go from “astronomical” (naturally, it’s power from the sun, nyuck nyuck) to “low margin.” But they’re still making money. Whoever built the nuclear plant is left with a very expensive stranded asset.
At least, that’s my understanding. I’m not a power company accountant. What I observe, though, is that power companies who do employ accountants aren’t building nuclear. They’re building shit-tons of solar. And I’m pretty sure it’s not because they’re hippies who hate nuclear.