HACKER Q&A
📣 kuczmama

Is it possible to dig deeper than the kola superdeep borehole?


Hello Hacker news, I’ve been chewing on this problem for the last few days, and wanted to get your thoughts on this.

So here’s the idea, we dig two super deep holes and connect them underground. The holes would be deep enough that the ground would be very hot maybe ~10 miles down or so. Then from one hole we pump water down it, warm it up, and then steam will come up the other side. That steam spins a generator and generates power. Then you cool the steam in a cooling tower and pump it back down and repeat the process.

We could use this process to renew all old coal plants. As opposed to burning coal, we could re-use the turbines and cooling towers that already exists in old coal plants. This would give old coal plants a new life, and could in theory get the world off coal.

What am I missing here? Does anyone have experience doing something similar? Do you think in 2022 we have the technology to dig a hole that deep?

Here’s a diagram I made of how the process could look: https://imgur.com/a/NTQPh15


  👤 WheelsAtLarge Accepted Answer ✓
Probably not, the deeper you drill the more expensive it gets - exponentially. It's probably many times less expensive to use other power sources. It's not trivial so every additional hole would take great effort.

Here's an article about a company that is trying to do that.

https://www.extremetech.com/extreme/332693-digging-the-world...

I hope they can do it. It would be a great achievement.


👤 riskpeep
Pretty much exactly what these people want to do...

https://techxplore.com/news/2022-02-quaise-energy-power-geot...


👤 ggm
Shallow geothermal is cheaper to exploit but it's still harder to engineer than people think. Nothing about deep boreholes is cheap.

The mohole and kola were science experiments. Not energy projects.


👤 Grimburger
> What am I missing here?

How absurdly expensive it is to dig even small width holes to that depth compared with other energy sources.