Grangegorman Demonstration Site, Dublin

Group of people walking on campus path with low level heating centre to right, with two short chimneys
The Grangegorman campus will host the first deep (about 2 kilometres) geothermal drilling demonstration on the island of Ireland.

The deep exploration well will provide valuable data on the geothermal heat potential of the most common geology on the island – carbonate rock. Predicting how much water can flow through carbonate rock (flow rate) is difficult due to lack of data on these deep reservoirs. Data from this borehole will help GEMINI scientists and engineers to predict flow rates, which affect heat supply costs, for areas with similar geology.

This demonstration will also enable GEMINI to construct best practice guidelines on deep geothermal drilling in urban areas, including technical, operational and planning information. It will also provide a living lab for engineering and sustainability programmes that will produce a future geothermal workforce.

Technological University Dublin (TU Dublin) will host the drill test site, which is primarily funded through the GEMINI project. Working with Grangegorman Development Agency (GDA - the owner of the site), TU Dublin will explore investment to create a functioning geothermal sourced district heating system.

If this site successfully demonstrates that deep geothermal energy can be used for heating in this area, the data and information gained from its development could be used by GDA and Dublin City Council (DCC) to expand the network and supply heat to other users.

  • Interested in how deep geothermal energy systems work? Check our FAQs.

  • Read on for FAQs about this demonstration site.

GEMINI partners involved in onsite activities at Grangegorman are: Geological Survey Ireland (providing technical support and advice); TU Dublin and associated partners DCC and GDA; Dublin Institute for Advanced Studies (geophysical surveys and research); University College Dublin (geological research); Codema; RML; TASC (communications and engagement).
Grangegorman demonstration site

FAQs
Why is TU Dublin investing in geothermal energy?

TU Dublin has identified geothermal energy as the best renewable heat source for the campus to reduce fossil fuel use and contribute to their Sustainability Strategy. The campus was recently redeveloped with a district heat network which includes a mixed demand system of older and A-rated buildings and is within a Near-Zero Emissions planning zone. 
Why is Grangegorman Campus being used for this geothermal demonstration?

In 2021 an exploratory borehole was drilled by GSI to a depth of 1 km, where a temperature of 38.5°C was measured. As temperature increases with depth, it is estimated that at 2 km fluids will be hot enough to use effectively for heating buildings. 

In addition, the campus has a mixed demand district heating network, enabling straightforward connection of a geothermal heat source to an efficient delivery system.
Where is the drilling site going to be located?

It is currently proposed to locate the borehole close to the existing Central Energy Centre (pictured above), west campus.
How big is the drilling rig going to be?

The exact drilling rig size will depend on availability when construction begins. However, a rig capable of drilling to 2,000 metres depth will have a mast height of about 30-55 metres – a lot lower than a tower crane. It will not be a permanent structure.

How long will the drilling last?

It is expected that the drilling will last two to three months.
Will the drilling be noisy?

Minimising any impact, including noise, is really important to us. The site design and choice of drilling rig will consider the potential noise level impact beyond the site and baffle systems will be used to ensure that any noise is kept within permitted levels. A noise monitoring system will be put in place.
Will there be vibrations during the drilling?

Like a construction project, some minor ground vibration is possible during the drilling. These will be very localised and carefully monitored. It is unlikely to be noticed outside the site boundary.

Can I visit the site?

Yes, there will be opportunities to visit the site and meet with members of the project. There will be a series of events for the local community to engage with the project.
What will there be to see when everything is complete?

Once the drilling is complete the only surface expression will be a small surface structure to contain the well head (a 20-25 cm diameter pipe with a series of control valves protruding 2-3 metres above ground). If this proceeds to a full geothermal heat installation, the pipe will become part of the TU Dublin Central Energy Centre.
Who do I contact if I have more questions?

You can email contact@geminigeothermal.com
Once there is more activity on site, there will be a dedicated contact person.

What happens next?

Keep an eye out on this web page for project developments. You can also follow us on social media for GEMINI updates.

Get involved!

Interest in geothermal energy is growing and we’re keen to connect with individuals and communities who would like to be part of the journey. Whether you’re a member of staff, a student, an onsite worker or local resident, there will be multiple ways to get involved as the project develops. Complete this form if you’d like to stay informed and find out about ways to contribute. 
Contact form