Small German town starts testing geothermal power utilizing new techniques | Hacker News Reader

Small German town starts testing geothermal power utilizing new techniques

apnews.com

93 pointsPaulHoule21 comments

Geretsried (the town) apparently sits in an ideal location for geothermal power and heat plants, in the same basin as Munich and other surrounding municipalities who have been leveraging geothermal energy to great effect.

https://geothermie-allianz.de/en/geothermal-in-bavaria/

I'm surprised we don't see more such projects.

Where it's feasible it might be cost. Perhaps it's still cheaper to pollute than to implement projects like this.

> I'm surprised we don't see more such projects.

The main reason why geothermal drilling has a difficult stand in Germany is the case of Staufen: https://en.wikipedia.org/wiki/Staufen_im_Breisgau#Geothermal...

> The cause for this geological change has been identified as a drilling operation conducted in the summer and autumn of 2007 to provide geothermal heating to the city hall.

That project was about transferring heat. Perhaps for geothermal electricity production which can happen away from population centres this is less of an issue?

There is a huge difference between "Geothermal Energy" technologies.

The project in Staufen seems to be about a heat pump, which is a really simple technology that can be used pretty much everywhere. The problem seems to be that the drilling hole hit a gypsum layer that started swelling. But this should be pretty easy to know if it is in an area at risk.

Lots of houses here in Sweden has this technology, my house has, and it is a 2 day project to drill a 150m hole for a standalone house and install the heat pump, maybe $20-30k investment.

Wikipedia claims Sweden is #2 in the world for geothermal energy, but it is because of these simple heat pumps.

https://en.wikipedia.org/wiki/Geothermal_heating#Application...

Heat pumps do not rely on hot water springs, it mainly just recycles old heat from the sun that has been stored in the ground over the season(s).

The project in the article talks about hot spring geothermal energy, which is more complex because it requires drilling holes several kilometers deep.

Why would I ever do a geothermal heat pump for $20-30k when you can get a proper central air heat pump and air handler for less than half? The split unit heat pumps a good portion of the world like would be even cheaper. Not sure how much those would cost.

Geothermal heat pumps are more efficient. They also ignore air temp so they keep working efficiently when cold outside.

The downside is that geothermal is expensive and hard to retrofit. They make the most sense in new construction in cold climates or adding to large properties.

Geothermal heat pumps can work great in retrofitting old system with a water heater. My family house is over 100 year old and the original water heater used coal in 1920, then it was changed to electrical around 1980s, and is now fitted with geothermal heat pumps. Geothermal was installed as a cost saving measure and cut down the heating bill by more than half. All the old cast iron radiators are still the original ones.

Yeah, best deal if you already have water based central heating and radiators. Which is pretty common here in Sweden since don't really have air/gas heating systems, so our houses are not built with air ducts.

Better efficiency (you use maybe 30% of the electricity), connects to the central heating so it supports the entire house.

I installed mine for $15k but that was 20 years ago and included subsidies.

There is no "away from population centres" in central europe

What? Look how much white there is: https://luminocity3d.org/WorldPopDen/#6/48.966/12.898

For more details what already exists, there is a map of deep geothermal power plants in the "Energie-Atlas Bayern" (in German) published by the government of Bavaria:

https://www.karten.energieatlas.bayern.de/start/?c=677751,54...

The "Energie-Atlas Bayern" includes also maps of other kinds of geothermal installations.

- A map of downhole heat exchangers:

https://www.karten.energieatlas.bayern.de/start/?c=677751,54...

- A map of groundwater heat pumps:

https://www.karten.energieatlas.bayern.de/start/?c=677751,54...

If you like small german towns, new power plants, and time travel you should watch Dark

https://en.wikipedia.org/wiki/Dark_%28TV_series%29

As well as long, boring, pseudo-scientific dialogues

Some extra information on cost:

"According to Robert Winsloe, Eavor’s executive vice-president of origination, the company expects its AGS technology to achieve an LCOE of $75/MWh by 2029–2030"

https://www.eavor.com/blog/eavors-innovation-promises-signif...

Map of Europe indicating where geothermal district heating resources are available: https://map.hugeo.hu/geo_DH/

Manual: https://web.archive.org/web/20240619080217/http://geodh.eu/w...

> instead, it’ll rise naturally to the surface

Well it isn’t rising to the surface thankfully because that would create an unbelievable amount of toxic pollution. it would also have to traverse through impermeable rock layers… otherwise we’d just have oil shooting through ground everywhere.

> through an outlet well

I see more. Pressurizing formations is pretty common in the oil and gas world. However, you can only do this with certain geologies. Most of the time it’s going to require fracking to get any kind of significant flow in most sedimentary rock geologies, because they’re simply is not enough flow through the formations.

The final note here is injecting fluids like this is that something that can be done everywhere. in some areas, this can actually cause miniature earthquakes because it’s lubricating slip planes.

Given Germany’s disastrous move away from nuclear power and the coal-lification of their power grid, Happy to see it them generate some actual clean power/heat, Is there one of the dirtiest producers in the EU.

*cough* Staufen im Breisgau *cough*

https://en.m.wikipedia.org/wiki/Staufen_im_Breisgau

They're fine, now. Tentative few years there though.

To add, there's now a weekly extraction of ground water to maintain the pressure.

It is an interesting test, but I wish they could provide a bit more details. Doing some searches it seems that this is a €350 million project, for which €100 millions is direct grants given by the government, and the remaining are special loans given out by different green investment initiatives. It is planned to generate 8.2 MW of electrical output (in practice they intend to divert some for heating, which mean less total electrical output but with higher amount of usable energy).

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