In Blanchardstown, another data centre looks to pipe hot water to heat nearby buildings

A Dublin-based company is working on a new project to use extra heat from data centres in the Blanchardstown area to heat water and pipe it to surrounding businesses – dialling back fossil-fuel use for that.

As part of a planning application to expand its operations out in Dublin 15, data-centre operators Pure DC said they plan to reduce carbon emissions in part by signing up to a district heating project being developed by HeatGrid Ireland.

"Pure DC are currently under an exclusivity agreement to work closely with Heat Grid Ireland ... to provide waste heat from the DUB01B project as key input to the development of a Heat Network in the area," the application says.

HeatGrid CEO David Connolly said by phone on 17 August that the company is "in the very early stage, the concept stage" with this project. But it's looking good so far, he said.

District heating projects involve a lot of upfront spending, in this case to build an energy centre to boost the temperature of the warm water coming out of the data centre to the level needed – and to install a network of pipes to deliver it to customers, among other expenses.

In terms of finances, HeatGrid is supported by Asper Investment Management, "a specialist investment management firm" focused on financing things like windfarms. It is also hoping to get some financing from the €50 million to €100 million the government last year set aside for district heating infrastructure, Connolly said.

Although district heating – warming a network of buildings with a common heat source – is common in some European countries, it is still nascent in Ireland. There's a pilot project in Tallaght up and running, using waste heat from a data centre to warm surrounding buildings, and some other projects in early stages.

Dublin City Council is slowly moving forward with a large project to use waste heat from the Poolbeg waste-to-energy incinerator to warm buildings. And Fingal County Council has been looking at a €58 million project to use waste heat from data centres in Dublin 15 to warm buildings around there too.

On the west coast, HeatGrid on 10 August got planning permission for a large district heating scheme in Galway.

When the government begins allocating grants to help support projects, "that's when schemes will begin to crystallise", said Connolly, who is also chair of the Irish District Energy Association.

Along with its push to decarbonise the electrical grid, by adding more wind, solar and batteries, and its push to decarbonise transport by increasing active travel and getting more electric vehicles on the road, the government has been working to reduce the use of fossil fuels for heating buildings by supporting district heating.

It's all, of course, an attempt to reduce greenhouse gas emissions, to try to blunt the pace of climate change, and so reduce its impacts on everything from biodiversity loss, to sea level rise, to extreme weather.

District heating in Dublin 15

Pure DC has a data centre campus in Ballycoolin, near Blanchardstown.

The company designs, builds and operates data centres in Europe, the Middle East and Asia.

And it's backed by Oaktree Capital Management, a Los Angeles-based investment firm. Which in turn is owned by the much larger New York-based Brookfield Asset Management, which says it has "over $1 trillion of assets under management across infrastructure, energy, private equity, real estate and credit".

This planning application to Fingal County Council out in Dublin 15 is part of the global buildout of data centres to host everything from the cloud-based document-collaboration software this was written on, to backups of our photos, to Elon Musk's Grok AI as it gives snarky answers on X and undresses women and children in photos on demand.

In Ireland, these data centres are using more electricity than all homes in the country's urban areas.

As part of its planning application, Pure DC included a "sustainability statement", written for it by Ethos Engineering.

"The proposed development amalgamates [data centres] DC2 and DC3 into a single refined DUB01B scheme, leveraging recent technological advances to enhance operational performance with increased on-site renewables, new grid connection for stability support, future district heating integration, and 100% renewable energy commitment," the document says.

The design includes measures to make the project ready for a future district heating scheme, should it be built, the document says, including buried pipework.

"District heating pipework is not included in the current scope of works but remains future-ready to accommodate expansion when demand and network availability align," it says. But "any ongoing or adjacent construction activities will account for this heat recovery potential, ensuring space and access for pipework, fittings, and accessories as required".

Pure DC has signed an exclusivity agreement with HeatGrid to export about 10MW of waste heat to its proposed adjacent district heating system, it says.

Is the HeatGrid district heating system in Ballycoolin a real project, or just something for Pure DC and other data centres trying to get planning permissions to put in their sustainability statements to make them look "greener"?

It's very much a real project, in early stages, which HeatGrid is trying to develop, Connolly said, pointing to the company's success in getting planning permission for the scheme in Galway as evidence of its seriousness.

Competition?

HeatGrid's proposed district heating project in Dublin 15 isn't competing for the same customers as Fingal County Council's one, Connolly said.

They're near each other, but with separate proposed sources of heat, and customers for that heat.

Fingal's plan has been to get waste heat from data centres – it mentioned an Amazon one – and, in phase one, pipe it to TU Dublin's Blanchardstown campus, Connolly Hospital, the National Sports Campus and other customers. Phase two would connect it to pharmaceutical plants, the IDA business park, and social housing in the area.

HeatGrid's plan, meanwhile, is to take waste heat from the data centres in Ballycoolin, and sell it to customers in that same industrial estate, Connolly said.

The reason these projects rely on waste heat from data centres, is that getting the heat as cheap as possible helps make the projects economically viable, and keep costs down for their customers, Connolly said.

The bills for customers of the Tallaght district heating project show they are currently paying a bit more monthly than they would if they were heating their homes with gas – although it reduces big-picture, global and societal costs in the long-term.

If district heating is the future for Dublin, how much will it cost customers?

The shift to a lower-carbon heating system would reduce big-picture costs, like, global costs, societal costs. But how would it affect customers’ bills?

Dublin InQuirerLois Kapila

A trash incinerator like the one at Poolbeg would deliver water at a relatively low cost and high heat, Connolly said.

A data centre can deliver water at relatively low cost and a lower heat – meaning the district heating system operator has to spend money to make that water hotter (probably with electric heat pumps) before delivering it to customers.

Engineers have mapped where there's potential to drill down into the earth under Dublin to find geothermal energy, which is constant (unlike wind and solar), and basically carbon-emissions-free (unlike gas). And TU Dublin's been drilling for it on its Grangegorman campus in Dublin city.

But geothermal energy would cost more to get than waste heat from incinerators and data centres, and come out of the ground at a lower temperature, requiring more money to raise it before selling it on to customers, Connolly said.

There's also more risk, he says. "Who's going to guarantee you that if you drill the hole you will get the temperature you think you're going to get?" he asks.

Connolly said HeatGrid is working on multiple district heating projects across the country, and expecting to apply for further planning permissions before too long.