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The time has finally come for geothermal energy

newyorker.com

71–80 of 282 posts

Re: The time has finally come for geothermal energy

#71

Baseload generation is useless in 2025. It's in the name; it's called "base load", not "base generation". Base generation was a cost optimization. Planners noticed that load never dropped below a specific level, and that cheapest power was from a plant designed to run 100% of the time rather than one designed to turn on and off frequently. So they could reduce cost by building a mix of base and peaker generation plan…

Modern geothermal is dispatchable. It's a really good compliment to wind and solar https://climateinstitute.ca/safe-bets-wild-cards/advanced-ge...

Re: The time has finally come for geothermal energy

#72

It's nuclear fission. It's always been nuclear fission (well, at least since the '50s) and it will continue to be until we commercialize fusion reactors. Everything else is nice to have but it's like NIH syndrome.

It could be but the US and EU have so far been unable to build commercial fission reactors without going 2x+ over budget in time and money. China is having success but even they are not projected to have nuclear account for more than single digit percentages of their generation. Maybe SMR's, thorium, 4th gen, etc will work out, but maybe not.

The US Navy consistently builds reactors on-time and in-budget

Re: The time has finally come for geothermal energy

#73
post #28
post #24

Earlier quoted context omitted.

> We can't even declare total victory with LED bulbs over incandescent. The LED bulbs I have access to (whatever's in the aisles at Home Depot, Costco, etc.) fail much more frequently than the incandescent bulbs I used to buy, and produce an uglier light that is less warm even on the softest/warmest color settings. My suspicion is that incandescents were at the "end" of their product lifecycle (high quality available…

Maybe buy your bulbs somewhere else? I'm yet to replace any of the LED bulbs I've bought over the past 15 years and honestly can't even remember the last time a bulb failed.

Mine fail all the time. Cheap Amazon Basics, expensive Phillips.

Do they fail more than incandescents? idk maybe not, but they fail much more often than their advertising would suggest.

Re: The time has finally come for geothermal energy

#74
post #71

Baseload generation is useless in 2025. It's in the name; it's called "base load", not "base generation". Base generation was a cost optimization. Planners noticed that load never dropped below a specific level, and that cheapest power was from a plant designed to run 100% of the time rather than one designed to turn on and off frequently. So they could reduce cost by building a mix of base and peaker generation plan…

Modern geothermal is dispatchable. It's a really good compliment to wind and solar https://climateinstitute.ca/safe-bets-wild-cards/advanced-ge...

But is it usefully dispatchable? Nuclear can be made dispatchable but it's not usefully dispatchable because the costs are fairly similar whether the plant is on or off.

Like nuclear, I believe geothermal has high capital cost and low running costs, suggesting that it isn't usefully dispatchable.

But that's too simplistic. A big limitation of geothermal is that rock has poor thermal conductivity. So once you remove heat it takes a while for it to warm up again. If you're running it 100% then you need a large area to compensate. OTOH, if you're running it at a lower duty cycle you likely need less area.

So if you know the duty cycle in advance, then you can likely significantly reduce costs. Yay!

But that also means that you likely can't run a plant built for low duty cycles continuously for 2 weeks during a dankelflaute. It's likely great for smoothing out daily cycles, but not as good for smoothing out annual cycles. That means it's competing against batteries, which are also great for smoothing out daily cycles, and are very inexpensive.

Re: The time has finally come for geothermal energy

#75

I've always been curious why a cost-effective widespread implementation of geothermal energy has never been considered a holy grail of energy production, at least not in the public debate. Much of the discussion is so focussed on nuclear fusion, which seems so much harder and less likely to be reliable.

> a holy grail of energy production

Since you're comparing it to nuclear, I'm assuming you mean electricity production here, not energy production?

It's always worth remembering that electricity only accounts for ~20% of global energy consumption (in the US it's closer to 33%).

I suspect people confuse these two because in a residential context electricity plays a huge part of our energy usage, but as a whole it's a smaller part of total energy usage than most people imagine.

But any serious discussion of renewable energy should be careful not to make this very significant error.

The Lawrence Livermore National Laboratory publishes a great diagram of US energy use: https://flowcharts.llnl.gov/sites/flowcharts/files/2024-12/e...

Re: The time has finally come for geothermal energy

#76
post #59
post #10

Earlier quoted context omitted.

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. Focusing on fusion .. I think that's a legacy of 60s SF, when the fission revolution was still promising "energy too ch…

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 producti…

I fully understand that waste management of fission reactors is a Very Big Deal. But I still stand behind the argument that opposing nuclear power in the 70s and onward is possibly the biggest own goal the environmental movement has ever achieved.

At worst, nuclear waste contaminates a discrete section of the Earth. Climate change affects literally everywhere. The correct answer would have been to aggressively roll out fission power 40-50 years ago and then pursue renewables. You can argue that other solutions would make fission power obsolete, but we would have been in a much better spot if it'd at least been a stepping stone off fossil fuels. Instead, we have 40-50 years of shrieking and FUD from environmentalists over an issue that can be kept under control with proper regulation. The US Navy has operated reactors for over 60 years without incident, proving it can be done with proper oversight.

TL;DR nuclear has issues, but I'd take it over coal every day and twice on Sundays, at least until something better can scale.

Re: The time has finally come for geothermal energy

#77
post #30

I've always been curious why a cost-effective widespread implementation of geothermal energy has never been considered a holy grail of energy production, at least not in the public debate. Much of the discussion is so focussed on nuclear fusion, which seems so much harder and less likely to be reliable.

Why not is explained in David McKay's book Sustainable Energy - without the hot air https://www.withouthotair.com/c16/page_96.shtml The problems are that rock isn't a good conductor of heat, so once you've cooled a bit down, you have to wait for it to warm up. Warming only happens very slowly at the rate of < 50mW / m² which limits the amount of power you can get out.

Couldn't you frac the rock like they do with oil and gas drilling or have a branching borehole?

Re: The time has finally come for geothermal energy

#78
post #9

Earlier quoted context omitted.

Not really how that works. Also earths core is being heated from nuclear decay and tidal effects. It’s getting 10’s or TW worth of heat until the sun expands and eats the earth. https://en.wikipedia.org/wiki/Earth's_internal_heat_budget

The world's total energy consumption (most of which is fossil fuels) is currently estimated at 620 exajoules, or 17TWh / year. Assuming zero growth in energy consumption (hello AI), extracting even half of that seems like it would be consequential.

I believe this is off by 5 or 6 orders of magnitude.

Looks like it's more like 200,000Twh / Yr

https://ourworldindata.org/energy-production-consumption

Re: The time has finally come for geothermal energy

#79

Baseload generation is useless in 2025. It's in the name; it's called "base load", not "base generation". Base generation was a cost optimization. Planners noticed that load never dropped below a specific level, and that cheapest power was from a plant designed to run 100% of the time rather than one designed to turn on and off frequently. So they could reduce cost by building a mix of base and peaker generation plan…

In 2025 the power consumption of my state (NSW, Australia) on any given day will be greater then 5 GW. https://www.aemo.com.au/energy-systems/electricity/national-...

This "there is no base load" idea is a ridiculous myth trivially disproven: every grid on the planet has continuous demands on it and they're quite significant (5 GW is about 50% the day time peaks).

It doesn't matter what the cost is, because later this evening or tomorrow morning I can guarantee you the same thing: my state will need at least 5GW of power to literally keep the lights on.

Re: The time has finally come for geothermal energy

#80

Drill baby drill! Seriously this would be such a dream! Turns out that the best battery is literally 10 feet away* - and you don't even need to charge it! *if you want to make steam its a few thousand, but for heating and cooling its literally just 10 feet!

Well, heat pumps are awesome, but ground-source is overkill for many places where the air temps don't fall too low (and it's a lot harder to drill holes behind your house).
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