Microsoft’s project in Espoo will generate slightly hotter water – 32.2 degrees Celsius – than Meta’s Danish system, partly because the Finnish data center will also have the capacity to power AI systems. Finnish energy company Fortum will then boost the heat to between 82.2 and 121.1 degrees Celsius before it enters people’s homes – which should happen sometime after 2025. The heat extracted from data centers that power AI tends to be hotter because they often have higher-density server rack setups, says Tom Glover, head of data center operations at real estate consultancy JLL. “You get higher quality heat, which can be better used within district heating networks,” he adds.
If Microsoft’s Espoo system is enabled, energy prices won’t necessarily be cheaper, said Teemu Nieminen, who leads the data center heat recovery project for Fortum. Neither company would reveal how much Microsoft is charging for the heat, but they did confirm it is part of a commercial agreement. It may not be cheaper, but prices should be more stable, Nieminen says, “compared to fossil fuels, where prices fluctuate very wildly.”
Microsoft also hopes that this stability will help make data centers at this scale more welcome in local communities, some of which are accept the issue with Big Tech sucking up vast amounts of renewable energy. “It will keep prices stable, and because people who live nearby know this… they are also more positive towards our data centers,” says Öhlund.
In Ireland, where data centers are labeled ‘energy vampires” by environmentalists and were responsible for 19 percent of the country’s total energy consumption last year, Amazon is giving away excess heat from its data center for free to the local university and local government offices, said John O’Shea, senior energy systems analyst at Codema, Dublin’s energy agency. Amazon’s donation is not an entirely selfless act. “We provide them with free cooling as a byproduct of absorbing their heat,” O’Shea adds.
So far the scheme is working. The project is expanding and the city is in the process of connecting the Amazon data center to more buildings and 135 apartments currently under construction. But O’Shea is wary of endorsing the data centers. Despite the heating project, there are still concerns in the County Dublin region, where there are between 65 and 70 data centers, about the amount of energy they use. “The development of data centers themselves is something that needs to be discussed,” says O’Shea. “But if they are developed, we think it makes sense to use this waste source, which would otherwise just be pumped into the air or waterways.”
A similar attitude exists in Denmark. Data centers will be responsible for 14 percent of the country’s total energy consumption by 2030, according to a forecast by the Danish Energy Agency. Big Tech data centers may get their energy from renewable sources, but a data center connected to local homes still requires the energy of more wind turbines than the homes would if they were heated directly by the turbines, says Henrik Lund, professor energy planning. at the Danish University of Aalborg. “The data centers themselves are putting pressure on the green transition,” he adds.