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Well that's it. One attempt failed. Scrap the entire idea.

Fervo engineers for thermal drawdown up front, it is well known that for EGS to maintain constant power output you need to periodically re-stimulate the field after a period of some number of years. What matters for the economics is the rate of eventual drawdown. The nameplate 100MW is also a bit misleading as it represents gross power output without taking into account the parasitic load of pumping which for an EGS plant is quite high. There was a ~60% parasitic load for their test facility and IIRC Fervo is eventually targeting 30-40% for the commercial power plant.

Would the deep-drilling approach enabled by Quaise alleviate this issue ?? I was super-interested when Quiase was first announced, but not sure if they are moving towards viability. Insights appreciated. Thx, NSC

Is there any reason to believe this is likely?

Enhanced geothermal are engineered geothermal systems in naturally hot dry rock where natural fluid convection and permeability are not found. The term comes from the fact that conventional geothermal power plants are often tapping into natural near surface convective systems with high water permeability. Bringing that heat to the near surface also heats the surrounding rock over hundreds of thousands of years so one way to "enhance" the output of traditional geothermal power plants was to theoretically engineer permeability into these surrounding rock formations. Fervo's facility is built next to an existing conventional geothermal power plant.

Yes! It's near where I live, very excited to see this come online.

I don't see why necessarily, they are in the same ballpark LCOE cost wise. The advantage of enhanced geothermal is that you can potentially build it relatively quickly but that is more a policy choice.

Does this support improved availability and economics of district heating?

Wiki page for that project: https://en.wikipedia.org/wiki/Frontier_Observatory_for_Resea...

Every project has risks, of course. EGS projects are basically two wells making a circulation loop: inject cold water down one well under pressure, circulate it through hot rocks using the fracked channels, and pull out hot water up the other well.

Theoretically, a leak into groundwater aquifers would make keeping the system pressurized harder or would dillute the amount of heat they're extracting, so seems like a stronger commercial incentive not to f up the groundwater.

In oil fracking they're just trying to pull the oily goo up from underground. And in theory you could do heat extraction using just water instead of shale goo solvents so any contamination would be less impactful?

I dunno, I'm just internet armchair quarterbacking this until a real geologist chimes in, but I can see how this is a somewhat different beast that shale fracking wells.

Huh, my first reaction was to say that Enhanced Geothermal is actually just a polite way of saying fracked geothermal but it turns out that's not quite accurate. Hydro-shearing (which EGS uses) doesn't intentionally create new cracks in the rock, which fracking does, but will cause existing cracks to grow. Potentially still negative local effects for sure but not as violently, hopefully.

Fervo was previously discussed on hn a couple months ago when they were hyping up this project: https://news.ycombinator.com/item?id=47903945

Some good info about what's different in there.

The new thing is using new-ish fracking drilling techniques to create a geothermal resource. Conventional geothermal relies on finding very specific geology which is why its so rare. Enhanced geothermal can (in theory) work in many more places since it can create the geology needed to produce electricity.

They’re using tech invented for fracking, so very conventional. The application for geothermal is what’s new.

> There are more than 50+ existing projects using EGS starting from the 1970s! What exactly is the "world's first" here?

First commercial operation with a grid connection. You'll notice that those 50+ are listed under the "research and development" section.

Does the build cost matter? After you've built the gas plant you still need to buy gas in perpetuity.

The marginal cost of the energy from the geothermal plant must be very much less.

This article also provides good analysis: https://powerstack.currence.ai/p/powerstack-post-ipo-fervo-c....

The tldr

> If we look at our Fastest MW analysis, the fastest way to get power to the grid right now is solar+BESS with existing interconnection agreements in ERCOT. This setup gives a 27-month or less time-to-COD, and can come in at $40/MWh PPAs, a price and speed Fervo can't catch. So, per the above, the right way to think about it is that Fervo competes for a different customer than the ones looking at solar+BESS. Are they required to procure geo? Are they in the West? Do they need fully baseload power? For sure, that’s a smaller niche. But if Fervo's anticipated 38GW resource base materializes even a little, the niche is huge.

Solar plus battery and some wind now beats everything else by such a wide margin it boggles my mind we’re even still talking about, or contemplating anything else.

By the time you finish reading this, solar panels got cheaper

> How come folks can’t conserve energy?

The whole economy runs on energy, and we have a lot of fossil fuels to replace.

No.