Engineered Geothermal Systems in Ireland

minnow

Hi,

there was an interesting article in The Economist a few weeks ago about the use of geothermal power to generate electricity through Engineered Geothermal Systems (EGS) http://www.economist.com/node/16909897?story_id=16909897 .

Wells are drilled to 4000-5000m (where it is 120-150C) and water circulated (down one well, back up another), and the resulting hot water is used to power a turbine via a heat exchanger. There is a vast amount of energy which can be tapped in this way, if it can be done economically (predictions of up to 80GW by 2050).

At the moment there are a few pilot plants in France and Germany, but there are plans to install commercial plants in Australia (where $2bn is being invested and more than 50 companies working on it) and the USA.

Current electricity production costs are high at an estimated $0.19 / kwh and most of the costs are upfront, as opposed to a fossil fuel power plant where the day to day fuel makes up a large percentage of the cost.

It looks as though some preliminary surveys and reports have been carried out some years ago by the SEAI:
http://www.seai.ie/Grants/Renewable_Energy_RD_D/Projects_funded_to_date/Geothermal_Energy/
and promising results found in Northern Ireland:
http://news.bbc.co.uk/1/hi/northern_ireland/7048686.stm

I find the concept very interesting and was wondering if anyone has heard of something similar being considered in Ireland, or if any companies are working on this here.


Minnow

*********************
Some more info on EGS
http://en.wikipedia.org/wiki/Enhanced_geothermal_system

FesterBeatty

You know this has been used on countless domestic projects throughout the country. Drill down to the required depth (usually around 200m in Dublin) and you've got free boiling hot water for life. Good idea if you've got the initial dough!

minnow

Yes, but I am more interested in the large-scale commercial power generation version.

enda1

FesterBeatty wrote: »

You know this has been used on countless domestic projects throughout the country. Drill down to the required depth (usually around 200m in Dublin) and you've got free boiling hot water for life. Good idea if you've got the initial dough!

200m in Dublin?

Really? Something doesn't add up about this.

Timmaay

I was involved in a project a few years ago to drill a 2k deep geothermal borehole in UCD to supply heat to the district heating system in UCD. At approx 2k deep the temperature is about 80degrees, and by the time you have pumped it up to the surface you have lost maybe 20degrees, so the biggest hurdle we faced was it was basically low grade heat, and would have been too difficult to supply to the district heating system.

Of course we could have used a heat pump, but the COP including pumping from 2k deep made it not worth while. Our estimated breakeven point at the time was at least 16years to recoup the capital cost, and that was when the price of gas was at its peak.

I don't know what killed the project in the end, but it would have been a massive capital investment and a very long payback time.

FesterBeatty

...oops - left out a zero!! 2000m...

minnow

By coincedence, this article appeared today on RTE.ie: Plans for Ireland's first geothermal generator, http://www.rte.ie/news/2010/0923/electricity.html

The company involved is GT Energy with assistance from ESBI on the generation side.
http://www.gtenergy.net/index.html
http://www.irishtimes.com/newspaper/finance/2010/0531/1224271503796.html

Interesting to see that something is going on in this field in Ireland.