From homes to offices, gyms and swimming pools, datacentre operators of all sizes are making positive use of the surplus heat their equipment emits
Running a data centre can be a lossy business in many ways. Power and heat exit from all angles from the moment they are generated and emitted: servers, storage, network gear are all culprits. Cooling itself can account for half of a datacentre’s power consumption and if that cooling is not functioning properly then the heat can be hits-you-as-you-walk-in-the-room intense.
With so much attention on datacentre power consumption, and so much money riding on the topic, matters have improved in recent years, however. Modern datacentres are largely unrecognisable from those of the last generation, from the sustainable ways they are powered to today’s skinny hardware and the levels of automation and tooling meaning that they are largely bereft of people.
And there is another positive too. What happens to the spare heat that is emitted in the datacentre. Over the past 20 years or so, a sizeable industry has arisen in capture, storing, and distributing waste heat. There is plenty of capacity for run-off heat to be more than just a neat way for companies to show off their ESG badges of honour and some companies are thinking very big indeed.
The giants have landed
Let us start with something on a vast scale. Microsoft announced last year plans to build a datacentre ‘region’, or group of tightly linked datacentres, in southern Finland, between the city of Nokia’s hometown Espoo and, a few miles away, the small town of Kauniainen. The datacentre region will feature Azure Availability Zones (ringfenced areas to protect against overall failure across a region) and is designed to provide local Finns with very low latency, data sovereignty and all the usual benefits of a state-of-the-art facility such as excellent cooling, security and regulatory compliance support.
Such is its potential that analyst IDC estimates the Microsoft datacentre region will generate more than €17.2 million in new revenue and provide 11,000 jobs. But here is the kicker: it will also provide the datacentre waste heat to warm the water supplies, buildings and homes of the local area via a network of insulated pipes.
The move even won a public plaudit from Finland prime Minister Sanna Marin, who hailed the plan as a win-win that could serve as a template for other countries seeking the double transformation of climate neutrality and digital competitiveness. Microsoft worked with Nordics clean energy supplier Fortum to heat the homes, businesses and public buildings of Espoo, Kauniainen and the municipality of Kirkkonummi to save what Fortum CEO Markus Rauramo says will be 400,000 tons of CO2 emissions per year. Microsoft reckons the project is the biggest of its kind in the world and it certainly appears to be a good fit for an area that see sub-zero Celsius temperatures for three months of the year.
A new leaf
In some ways Microsoft was taking a leaf from the datacentre playbook of Meta, which uses its Odense Denmark datacentre’s spare heat to warm about 6,9000 of the city’s homes. It even has its own Facebook page with nearly 4,000 followers. But lots of companies in the datacentre space follow the same principles from Yandex and Academica in Finland to similar projects all over the world.
Other datacentre leaders are also getting creative and not necessarily just in cold-climate countries. An IBM datacentre warms a community pool in Switzerland, Telecity uses its Concordet datacentre to heats its Climate Change Arboretum display in Paris, where scientists figure out which flora will survive changing weather models. While a UK university surely delighted students by heating its hydroponics studio.
These are all creative ideas and great PR, judging by the headlines such stories generate. Speaking of which, a special mention for Canadian communications company Quebecor for taking pity on the media by warming a local newspaper’s editorial office.
Not just for the behemoths
Smaller companies can do something similar though. “It is not limited to larger companies and cloud platforms,” Jakob Jul Jensen, head of business development for the datacentre vertical at Danfoss, which makes software, heat recovery units, heat pumps and energy transfer stations needed for full heating re-use solutions, says. “It is an even more obvious way forward for the likes of edge data centres and installations, which are more often located in close proximity to the heat off takers.
“Our own containerised datacentre, which will be sized for a 1MW IT load when it’s built out, is a great example. Here, the heat our own IT equipment is producing can be reused in our own factories and offices for space heating and hot water.”
In truth, most of this is not new but what is remarkable is the sheer scale and chutzpah of the biggest offerings and the increasingly turnkey in-a-box nature of solutions for smaller companies.
Jensen says there is a mindset change going on, rather than merely a technology wave in favour of recycled heat. “The shift is not driven by technology developments,” he adds. “We have for years been saying many of these opportunities in the green transition we are observing now rely on technologies which are readily available. The same is true for heat reuse. What is becoming clear for most is that excess heat is the world’s largest untapped source of energy.
“In Europe alone, excess heat amounts to 2,860 TWh/y, corresponding almost to the EU’s total energy demand for heat and hot water in residential and service sector buildings such as schools, hospitals, hotels, restaurants, offices and shopping centres. This is huge!”
Others in the sector are similarly bullish.
“We estimate 30 per cent of industrial commercial heat could be provided by this technology. Think distilleries, bakeries laundrettes and [residential blocks] with centralised boilers,” said a spokesman for Deep Green, a UK startup which recently won torrents of coverage for heating pools and leisure centres using its datacentre heat recycling tech. The company’s punch mission: to replaces all datacentres without heat recapture by 2035.
The future of datacentre heat recapture appears bright and a boon for sustainability with advocates suggesting more applications form clothes drying to food production. It’s a contribution to a world fighting rising utility prices… and even and even lobster breeding according to Danfoss’s Jensen who references a useful by-product of a Norwegian undersea datacentre. In a world struggling to cope with Net zero targets and to keep its people safe and warm, the heat if very much on. But in modern datacentres, an alternative is being showcased.
