Datacenters Feeling The Heat To Turn Hot Air Into Cool Solutions

Datacenters generate lots of heat and myraid providers are trying to put this resource to use, but there are geographic and various practical limitations on re-purposing it.

A new report by Uptime Institute highlights the current state of so-called heat reuse projects and the challenges that datacenter operators and national and regional authorities face in making these schemes work.

While datacenters consume a lot of energy, most of this gets converted to heat, requiring the use of cooling systems to prevent overheating.

With an eye on sustainability and climate legislation, the industry continues to seek ways to make use of the resultant waste heat for other purposes, often for heating homes or other buildings. This is just as well as the current AI boom is driving a trend for ever more power-hungry infrastructure.

Uptime Institute notes that Northern Europe leads the way in this area, partly for climate reasons. It also notes that implementing a heat reuse project at a datacenter introduces new factors into the planning process, such as ensuring there are nearby users for the heat produced.

This adds complexity and calls for additional engineering and a sizeable upfront investment by the datacenter operator for equipment to transport the heat to users.

Uptime Institute reckons that selling waste heat to generate extra revenue is complicated by the heat output of the bit barn and the price of the energy delivered both being variable according to the season, which often leads to operators simply offering the waste heat for free.

The report finds that capturing the heat and making it available for reuse typically has a neutral or negative effect on energy efficiency, because the need to employ heat pumps in order to boost the temperature of the water involved may increase the total energy consumption.

However, when datacenters are considered as part of a larger system such as a city district, heat reuse schemes can have lower overall energy consumption and greenhouse gas emissions, Uptime Institute's report says.

Last month, the UK government claimed it was investing up £36 million ($41.4 million) to support a scheme in West London. This would see heat from datacenters used to provide heating and hot water for 10,000 new homes in what is styled as a "low carbon housing estate of the future."

• Hyperscale datacenter capacity set to triple because of AI demand
• UK throws millions at scheme to heat homes with waste energy from datacenters
• Plans for Dutch datacenter to warm thousands of homes
• Microsoft datacenter to heat homes in Finland

Nordic datacenter operator atNorth has also just disclosed plans to build a new facility at Kouvola, northeast of Helsinki, Finland, that will recycle excess heat from a datacenter for reuse within the local community.

Uptime Institute estimates there are currently about 60 datacenter heat reuse projects in Europe, with six in North America and a further 11 projects said to be in development or under construction.

New legislation aimed at limiting climate change may also make these projects more common. The EU's revised Energy Efficiency Directive (EED) says that datacenters with an IT capacity of 1 MW or greater should "take into account the best practices in the European code of conduct on datacenter energy efficiency," which in practice means implementing waste heat recovery or showing that it is unfeasible.

Meanwhile, a German upcoming law – the Act to Enhance Energy Efficiency, Improve Climate Protection and Implement EU Legislation (Energieeffizienzgesetz, EnEfG) – is putting pressure on DC operators as it sets out a legal framework for datacenters that contains references to mandatory reusing of excess heat. It all kicks off in 2025, when newly built DCs will have to reuse 10 percent of their excess heat.

The Register has covered a number of proposed schemes for using waste heat from datacenters over the past year or two. These include the London scheme mentioned above, one by Dutch outfit Bytesnet to supply heat to homes and businesses from a new datacenter in Groningen, and one by Microsoft and Finnish energy company Fortum to transfer heat to homes in Espoo, Kauniainen, and Kirkkonummi.

However, the most unusual scheme remains that of a datacenter in Hokkaido in Japan, which is using snow to cool its IT infrastructure then taking the resultant warm meltwater to cultivate eels for sale at market. ®