Nordic data-center operator Digiplex and Stockholm Exergi, the Swedish capital's leading energy supplier, are going to be using excess heat from servers to warm the equivalent of 10,000 households.
The two companies say their large-scale heat reuse agreement is the world's first where an operational data center with indirect evaporative air-to-air heat exchangers is being retrofitted to transfer excess heat to a city's district heating grid.
Digiplex says that a progressive data center needs to explore every avenue to reduce its carbon footprint, with the world's data centers responsible for two percent of the world's annual CO2 emissions, and three percent of the world's power consumption.
"Every time we browse the internet, stream a TV series or use the cloud, a process starts in a data center," said Digiplex CEO Gisle Eckhoff in a statement.
"If that data center is a power-hungry fossil fuel-fired one that releases excess heat into the atmosphere, we as individuals are contributing to climate change."
He added that digitalization needs to support improved sustainability, and using excess heat from Digiplex's Stockholm data center to heat thousands of households is an example of what can be achieved.
"This partnership with Stockholm Exergi is a big leap forward, one that could enable residents' digital activity to contribute to heating their own homes."
Close to 90 percent of all buildings in Stockholm are connected to the district heating network, making the Swedish capital one of only a few cities in the world where large-scale heat reuse from data centers is feasible.
The agreement also plays well into the city of Stockholm's ambitious plans for green operations, based on smarter use of technology.
Stockholm mayor Karin Wanngård said digitalization must go hand in hand with the development of environmental technology.
"Utilizing smart technological solutions to make the most of synergies between recovered data-center heat and the city's heating needs is a part of the environmental objective to become fossil fuel-free by 2040," Wanngård said.
"I'm determined to make Stockholm a major hub for sustainable data centers."