Geothermal Power is Finally a Reality

Started by RE, Jul 30, 2023, 03:04 AM

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RE

Here is a technology that could keep a technological society going, at least for a portion of the global population.  How big a portion I don't know, because I don't know how many locations are suitable for geothermal development or how much total power they could output.  To try and distribute this power, you also have the issue of being able to transmit it from where it can be sourced to where it is needed, aka wiring it into the grid.  On the upside, it is constant 24/7 power with zero carbon emissions and little waste I can think of.

According to the article, geothermal power is acccessed in 23 countries, though to what extent I do not know.  I know Iceland generates a lot this way.  The article claims this new plant is breakthrough tech, so perhaps we will be hearing more about it.

Geothermal Power is Finally a Reality After Next-Generation Breakthrough of Carbon-Free Energy in Nevada

https://www.goodnewsnetwork.org/fervo-energy-breakthrough-in-next-gen-geothermal-power-in-nevada/

RE

K-Dog

The article has no technical details.  How deep is the well?  How much power can be extracted for how long?  How long is it before energy returned exceeds energy invested.

Is the geothermal 'breakthrough' like a fusion 'breakthrough'?  Much fanfare about the fusion reaction at Laurence Livermore producing three times the energy pulsed lasers fired at a target in December.

And not much mention that the lasers need 100 times the energy they put out to fire in the first place.

This article is typical of geothermal articles intended for the general public.   Details? who needs them!

 

No worries.


K-Dog

#2
This gets me thinking.  Could a person create a backyard geothermal system akin to a home solar farm?

The best heat pump arrangements run heat transfer lines in the ground.  Hoses looped in buried back yard trenches transfer heat into to ground to cool in summer and heat is extracted from the ground to heat in winter.



Could lines carry water to a heat exchanger where heat is used to boil a refrigerant to generate power.  The refrigerant drives a motor generator.  In winter refrigerant is condensed by a fan blowing air through a radiator.  In summer the arrangement reverses.



Efficiency is low.  based on the Second Law of the Thermodynamics, the maximal effectivity of any heat engine is 1−TC/TH. TC and TH are the temperatures of the cold and warm heat tanks.

But we do not care about efficiency if enough power is generated to meet needs.  A working system which keeps a building at a comfortable temperature would work until a component fails.  Low efficiency would mean a lot of coils in the ground.  But that is out of sight out of mind.  Literally.  Low Efficiency pushes the break even point out a few years.  That is also out of sight.

Efficiencies would be 10% or less, and that explains why nobody has put much effort in this direction.  The wide availability of cheap fossil fuels keeps interest in geothermal solutions on the back burner.

Perhaps a competition can 'unearth' needed technical details like the a maze robot solving competition has done for maze solving robots.



Micromouse Rules  <--  Robot competition rules.

However, I doubt many nerds in inner city or (outer city) apartments have back yards with which to experiment with heat pump systems.

RE

Quote from: K-Dog on Jul 30, 2023, 08:51 AMThe article has no technical details.  How deep is the well?  How much power can be extracted for how long?  How long is it before energy returned exceeds energy invested.

Granted the article was thin on technical details, but there was this:

The 30-day well test, a standard for geothermal, achieved a flowrate of 63 liters per second at high temperature that enables 3.5 MW of electric production, setting new records for both flow and power output from an enhanced geothermal system.

3.5 Mw is pretty decent amount of power.  It could power about 2000 homes, a small town.

RE

K-Dog

Old faithful erupts about once an hour and squirts out about 20,000 gallons of boiling water each time.  There are 3600 seconds in an hour.  That is an average flow rate of about twenty liters a second.

But since the eruptions only last three to five minutes I could easily claim 250 liters a second.

The devil is in the details. 




RE

Quote from: K-Dog on Jul 30, 2023, 10:11 PMOld faithful erupts about once an hour and squirts out about 20,000 gallons of boiling water each time.  There are 3600 seconds in an hour.  That is an average flow rate of about twenty liters a second.

But since the eruptions only last three to five minutes I could easily claim 250 liters a second.


The technique being used here doesn't require erupting geisers of the Old Faithful kind, which are relatively rare. It just requires an underground heat source, present anywhere the earth's crust is relatively thin or where there are cracks which allow the magma from the earth's mantle to come up near enough to the surface to be within drilling range for the kind of horizontal drilling done to extract shale oil.  Range there is down to about 10,000 ft.  Hawaii around Mt Kilaueha is a good example, as is just about all of Iceland.  These type of volcanoes don't usually erupt explosively like My. St. Helens, most of the time they just push out magma to the surface where it cools and hardens.  Right under the surface though there are large pools of molten lava.

The trick here is to drill down to just above a large pool of molten rock and run pipe through which you pump cool water and the magma just below the pipe acts like a burner to heat this water to just below boiling temp at 190F.  This comes back up the pipe to the surface where it runs through a heat exchanger and boils a refrigerant that runs a turbine.

The only limitations on flow rate are how big and how many pipes you run and how much water you can run through before you start cooling down the magma pool.  Bigger the pool and faster it is getting heated up from magma lower down, the more water you can pump through it before you start cooling it too much.

According to the article, their pilot well pumps 63L/sec and they plan a larger one for their next project.  The only question here is how many places have a magma pool large enough and close enough to the surface to drill down to and run the pipe.  They don't even really need much water for it either, since it is a closed loop system.

RE

K-Dog

#6
Reaching lateral lengths of 3,250 feet, reaching a temperature of 191 °C.

That is something, but lengths implies more than one, so we are back to square one.

The article also mentions a 'breakthrough'.

A breakthrough implies something new.  Something Iceland has not done in 30 years?

Too bad the article won't says what it is.

Geothermal is not something that really needs an innovation.  Existing technology provides the tools and techniques needed.  What Geothermal needs is blood sweat and tears.

**********************

The reason the article exists is to show Google spending money to purchase 'green' technology.

It will take more than that to get Google off my shit list.

You do know that this blog can't be found with Google right?  I have seen three bots at a time viewing this site at once.  But only the Legacy Diner page shows up in a Google search.  Google does exactly what the censors in Homeland Security tell them to do.  I am sorry to bring my history as a suspected domestic terrorist with me, but I really don't have anything to do with it.

I added 'Doomstead Diner' to the metadata for the page.  Bots can't miss it.  They do.

Of course if we ever get serious traction here we will appear as normal as apple pie and show up in a search.

Think what the Weimar Republic could have done with the the Nazi party when it only had 12 members and a website.  That would have been a good thing. 

Ranting on street-corners would not attract Berlin crowds had there been an net then.  Hitler could have practiced in front of a mirror all day long and it would not have done his movement any good.

That would have been a good thing.

But our Weimar repubic of the Stars and Stripes stops not just crazies.  Everybody is stopped, except for the sanctioned few.  Change WILL NOT BE ALLOWED.

And doom is baked in the cake.

RE

Quote from: K-Dog on Jul 31, 2023, 11:14 AMReaching lateral lengths of 3,250 feet, reaching a temperature of 191 °C.

That is something, but lengths implies more than one, so we are back to square one.

The article also mentions a 'breakthrough'.

I think the "breakthrough" they are talking about is to apply the horizontal drilling technique the frackers use to setting up a geothermal collector. They could make better use of a source  by laying several pipes across a magma pool.  More surface area to heat the water.  Not a huge technological leap though.

[/quote]
QuoteAnd doom is baked in the cake.

This of course is true. "baked" is a good choice of verbs. It's too little too late and doesn't address the problems of overshoot, resource depletion and climate change.  Even if we stopped all carbon emissions now, the climate will continue warming another 40 years at least.  Think this summer is hot?  You ain't seen nuthin' yet.

RE