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> as if no amount of solar and wind power generation capacity could be an adequate substitute for any amount of geothermal power, because you don't have solar power at night, for example. But actually that's just a question of how much it costs to store the energy until it's needed or transmit it from where it's still being produced.

I guess this depends on the region, at least to some extent. In Northern Europe we've had these periods during fall/winter in recent years where it's cold, essentially dark, and (worst) no wind. It's not really feasible to store ≈multiple days of consumption for tens of millions of people.

In three of the four Swedish price regions I think we are essentially in a situation now where wind power is "worthless" and can't be built out any more, at least not without major changes to consumption patterns. When the wind is blowing there is such high production that prices go almost to 0, and the operators earn ish nothing, and when prices go up there is no wind so no-one can produce.

Storing multiple days of consumption is feasible but definitely harder than the usual case of storing hours.

The pricing problem sounds like an artifact of how you've structured the market, not a fundamental obstacle to the profitability of intermittent power sources.

An alternative structure that would solve the problem would be for generation operators to buy put options for energy they expect to be able to produce, eliminating the risk of a price collapse. Consumers who want access to such intermittent energy would have to write those put options, which would be limited to particular times on particular days when they could use the energy. Having written the option, they would have to accept the generation operator's decision whether or not to exercise it. Utility-scale storage providers could write puts for low-demand times and buy puts for high-demand times, or they could write puts for low-demand times, write futures contracts for high-demand times, and make up the shortfall on the spot market. This might produce major changes in consumption patterns, but, more likely, would enable continued investment to minimize those changes.

I think this would show the true cost and unviability of the system. Which would be good.

I agree wholeheartedly, though I suspect we may have very different ideas about how much the true cost is and how much unviability there is.

A step forward would be to show for all those solar/wind + battery proposals the expected uptime and distributions given historical weather and how climate change might affect that.

For example this solution would be sufficient and have no blackouts/brownouts per year in 99% of historical data....

We can do a pretty good job of predicting solar and wind production; that's done routinely. What's harder is predicting how load will change when electric energy is nearly free in most daytimes and expensive on calm nights.

That does not matter. You can only postpone washing your clothes for so long and heating in northern winters is non optional. The problem are things like: https://en.wikipedia.org/wiki/Dunkelflaute

Extreme weather events are what is important and we do have the data.

Heating in particular is an especially easy problem to solve; various kinds of thermal energy storage (sensible-heat, phase-change, TCES) can store heat for later climate-control purposes several orders of magnitude more cheaply than batteries. Washing your clothes is a harder problem, although a stockpile of clean clothes is easily stored.

Predicting how willing Swedes will be 10 years from now to buy extra jeans and install phase-change energy storage in their houses, however, that's beyond anybody's ability.

You are right there is no getting around that relatively low grade heat in geothermal is a big barrier for scaling in terms of energy production. Binary /organic rankine cycle geothermal plants used for these low / medium temperature resources operate at ~10% efficiency. Dry / flash steam resources are higher but produce waste in terms of emitted GHG and / or crap in the geothermal brine.

Deep geothermal promises to provide what is usually considered high-grade heat (800+°), but what I'm trying to understand is how cheaply you can convert that high-grade heat into electricity, because the answer seems to be "far too expensively to be competitive with wind and solar".

Supercritical geothermal is similar to talking about the economics of fusion. There is a DOE enhanced geothermal test site near the Newberry Volcano in central Oregon which has temperatures close to this range at reachable depths. That is more of a demonstration site for drilling technology.

Yes, but if (as I am claiming) there's no way to economically turn heat into electricity, it's irrelevant whether supercritical geothermal steam costs trillions of dollars per borehole or is free; either way it's uneconomic as a source of electricity.

Cost is an artificial construct (see: oil subsidies, corn subsidies, EV subsidies, and so on). "It's too expensive!" is such an uncreative response to technology we desperately need to stop overheating the planet.

Cost describes tradeoffs. Environmentalists ignoring costs and generating a backlash that completely undoes their work shouldn’t be a lesson needing relearning twice a generation.

Thank you for saying this. I didn't have the patience, and it's a rather subtle issue with a lot of nuance.

Tradeoffs are indeed inherent in any human effort, but actual market prices are an imperfect reflection reflection of those inherent tradeoffs, and can indeed be distorted by subsidies, externalities, etc. And often tradeoffs cannot really be reduced to a single scalar the way costs do—not everything can be traded off against everything else.

Yet that observation does not mean there aren't any real tradeoffs, or real tradeoffs that can be reduced to a single number.

Also, while this god's-eye viewpoint of the options available for collective action by humanity as a whole is important, for most of us it isn't useful tactical or even strategic information about the possible courses of action we could undertake to affect the world, much less our own lives. It's most useful if you're a billionaire, a Central Committee member, or a Civ player. For the rest of us, even Bilderbergers and the like, those subsidy-distorted costs and the failures of collective action that produce them are merely facts about the world; we cannot make them evaporate in a puff of logic by pointing out their irrationality.