alt Hacker NewsDrilling is one of those things which used to be extremely expensive but has very gradually come down in price. Thanks, ironically, to the oil industry. It's unsexy because there's no "silver bullet" waiting in the wings.
It's also quite hard to find suitably hot rocks suitably close to the surface.
Focusing on fusion .. I think that's a legacy of 60s SF, when the fission revolution was still promising "energy too cheap to meter".
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> Drilling is one of those things which used to be extremely expensive but has very gradually come down in price. Thanks, ironically, to the oil industry. It's unsexy because there's no "silver bullet" waiting in the wings. It's also quite hard to find suitably hot rocks suitably close to the surface.
That's basically it. Most geothermal plants today are in locations where there are hot rocks, maybe geysers, close to the surface. "Deep geothermal" gets talked about, because temperatures high enough for steam are available almost everywhere if you can drill 3,000 meters down. There are very few wells in the world that deep, not counting horizontal drilling runs.
The economics are iffy. You drill one of the most expensive wells ever drilled, and you get a medium-pressure steam line. Average output is tens of megawatts.[1]
[1] https://pangea.stanford.edu/ERE/db/GeoConf/papers/SGW/2020/A...
Plasma drilling is a recent development that looks promising for unlocking deeper wells for geothermal.
Many others here have talked about the difficulties of geothermal, which doesn't really get to the heart of my question: why the lack of hype around breaking down those difficulties? I appreciate that you took the time to comment on why it isn't so sexy, the SF argument probably has a lot to do with it.
To be fair, that promise of fission made sense from a purely scientific and mathematical perspective, before running into the practical realities of how its externalities interact with real-world politics. Fission is expensive because in practice it turns out we care quite a lot about proper waste management, non-proliferation, and meltdown prevention.
In a world where anyone could just YOLO any reactor into production with minimal red tape, consequences be damned, fission energy would actually be extremely cheap. Hence the optimism around fusion. The promise of fusion is an actualization of last century's idealistic conception of fission. It can be a silver bullet for all intents and purposes, at least once it's established with a mature supply chain.