In Vienna's Floridsdorf district stands Austria's largest data centre, and it heats a hospital. Heat pumps operated by Wien Energie, the city's utility, extract energy from the roughly 26-degree cooling water of Digital Realty's server halls and raise it to as much as 82 degrees – enough to supply the Klinik Floridsdorf hospital with district heating. It is a flagship project, and it captures both sides of a development that is currently accelerating dramatically: data centres are becoming major consumers within the electricity system, and at the same time an energy source that almost nobody has tapped until now.
June demonstrated just how fast that acceleration is running. On 16 June 2026, SpaceX announced it would acquire the AI company Anysphere, the firm behind the coding tool Cursor, for 60 billion dollars – four days after its own record stock market debut, entirely in shares, the largest acquisition of a start-up ever recorded. The deal is a symptom: the five biggest hyperscalers – Amazon, Microsoft, Alphabet, Meta and Oracle – have announced combined investments of 660 to 725 billion dollars for 2026, much of it earmarked for AI infrastructure. And every one of those dollars ultimately ends up where artificial intelligence physically exists – in data centres that need electricity. A great deal of electricity.
What the IEA expects by 2030
The International Energy Agency (IEA) has put a figure on the scale in its report "Energy and AI": global electricity consumption by data centres is set to roughly double from around 485 terawatt hours in 2025 to about 950 terawatt hours in 2030. That would amount to some three per cent of global electricity demand – and more than Japan consumes in total today. The share attributable to AI applications is growing fastest of all: according to the IEA, it is expected to triple over the same period. As early as 2025, electricity consumption by AI data centres rose by 50 per cent according to IEA figures, and by 17 per cent across all data centres.
Europe will not be spared either, albeit on a smaller scale: the IEA anticipates growth of more than 45 terawatt hours at European data centres by 2030, an increase of around 70 per cent. In its report "Electricity 2026", published in February, the agency also projects that global electricity demand will rise by an average of 3.6 per cent per year through 2030 – one and a half times as fast as in the preceding decade. Data centres are among the main drivers, alongside air conditioning, electric cars and heat pumps. For the EU, the IEA expects demand growth of around two per cent per year to 2030.
For perspective: the whole of Austria consumed 66.75 terawatt hours of electricity in 2025, according to the energy regulator E-Control. The growth in European data centres alone through 2030 thus equates to more than two thirds of Austria's total consumption.
Ireland and the Netherlands: two warnings
Where unchecked growth can lead is on display in Ireland. There, according to the grid operator EirGrid, data centres were already consuming around 22 per cent of the country's entire electricity in 2024; in the Greater Dublin area, home to almost all of Ireland's data centres, their share amounts to roughly half of regional demand. The consequence was a de facto connection freeze: since 2021, new data centres around Dublin have received practically no grid access. Only in December 2025 did the regulator CRU lift the moratorium – under strict conditions. Anyone wanting to connect to the grid in future must bring their own generation or battery storage matching their connection capacity, and must feed power back into the grid during shortages.
In the Netherlands, the problem is broader: across large parts of the country, the electricity grid is simply full. According to reports in the Dutch media, more than 14,000 companies were waiting for a grid connection or an upgrade from the transmission operator TenneT and the distribution networks in October 2025, and the wait for large consumers can stretch to ten years. For large parts of the province of Noord-Holland, TenneT has announced that there will be no additional capacity for major consumers – explicitly including data centres – until well into the 2030s.
Ireland shows what happens when data centres grow faster than the grid. Austria still has the choice to do things differently.
Both countries were early movers and spent years actively courting the data centre industry. Today they are struggling to reconcile that growth with climate targets and grid stability. For countries only now becoming a destination, it is a blueprint of what to avoid.
Austria is becoming a data centre country
And Austria is becoming a destination right now. The trade magazine report.at currently counts around 50 data centres in the country with a combined consumption of roughly 1.4 terawatt hours, nearly half of them in and around Vienna. That is a good two per cent of national electricity consumption – for now. Because the project list has grown long.
The biggest scheme is in Upper Austria: in Kronstorf near Enns, Google broke ground on 23 April 2026 for a data centre on a site of some 500,000 square metres. At full build-out, the facility is expected to consume up to 3.5 terawatt hours per year, according to media reports – as much as around 900,000 households, and more than double all of Austria's existing data centres combined. The transmission operator APG is building a dedicated new 220-kilovolt supply ring for the project and expanding two substations. In Lower Austria, Microsoft has operated three sites around Vienna since 2025, together forming the "Cloud Region Austria"; the Wiener Netze grid company had to build a dedicated switching station to serve them.
Just how big the appetite really is emerges from the data centre strategy that the province of Lower Austria presented in April 2026: it currently holds enquiries for projects with a connection capacity of around 3,400 megawatts – on paper, twice as much as the entire province consumes in electricity today. Not all of it will be built; much of it consists of duplicate enquiries from project developers. But the figure shows the pressure that can build on the grids if siting goes unmanaged. Add to that Vienna's bid for one of Europe's AI gigafactories, submitted in June 2025; if successful, construction could begin in 2028. And for anyone wondering why this matters to everyone: grid expansion is financed through network charges, which are already under strain, as a look at electricity prices in Austria in 2026 shows.
Vienna-Floridsdorf: where the waste heat isn't wasted
Back to Floridsdorf, because that is where you can see how it can be done better. Digital Realty, operator of the country's largest data centre campus since its takeover of Interxion, is expanding the site massively: the new VIE13 building is set to deliver around 40 megawatts of additional IT capacity on a 22,000-square-metre plot, according to the company, and is billed as Austria's first "AI-ready" data centre. Around 250 million euros are going into the first construction phase, due to come online at the end of 2026, and more than 400 million into the full build-out.
The decisive point, however, lies in the cooling concept. Data centres convert practically their entire electricity consumption into heat, which is usually released into the air via cooling towers – a double loss. In Floridsdorf, it is put to use instead: since the 2023/24 heating season, the waste heat has warmed the neighbouring Klinik Floridsdorf via three one-megawatt heat pumps operated by Wien Energie, and the new campus is to feed its waste heat into Vienna's district heating network. report.at describes the scheme as Austria's largest waste-heat project. Lower Austria's data centre strategy likewise makes waste-heat recovery and proximity to substations central siting criteria – an approach that Ireland and the Netherlands introduced only after the fact, and painfully.
Whether that will be enough hinges on a question nobody can seriously answer: how long will the AI investment boom last? The 60 billion dollars for Cursor amount to a multiple of the company's annual revenue, and Elon Musk's conglomerate of rockets, satellites and AI has, beyond the balance sheet, a considerable environmental bill outstanding. If the bubble bursts, half-built halls and oversized grid connections will remain. If the boom holds, the industry's electricity demand will double within a few years. For Austria, that means the question is no longer whether AI data centres are coming. They are already here. The question is whether their electricity is clean, their locations wisely chosen – and whether their heat warms more than just the atmosphere.