Equinix's Data Centres are Heating Milan's Duomo & Palazzo

When people think about powering a city's heating system, data centres are unlikely to come to mind.

Yet in Milan, heat produced by thousands of servers is being recovered and converted into usable energy for the city's district heating network, creating a new low-carbon heat source for homes and public buildings including the Duomo and Palazzo Reale.

The initiative highlights how digital infrastructure can also play a growing role in supporting urban energy systems.

Equinix's ML5 data centre at the company's Settimo Milanese campus will provide the recovered heat, which will be transferred to a new A2A Energy Center before entering Milan's district heating network.

Once fully operational, the development is expected to rank among Europe's largest data centre heat recovery schemes outside the Nordic region.

“Equinix has a long and proud history of aligning the needs of our business with the needs of the communities we call home," says Adaire Fox-Martin, CEO and President of Equinix.

“Our collaboration with A2A is a clear example of how essential digital infrastructure and local sustainability goals can work in service of each other.

“By putting thermal energy from our operations to use for local homes and residents, we're eliminating waste and moving Milan toward a low-carbon future.”

Making heat a circular economy

At the centre of the project is the capture of thermal energy generated by servers operating within Equinix's facilities, turning what would otherwise be wasted heat into a reliable source of energy for Milan's heating network.

Equinix will oversee the design and operation of the infrastructure required to export heat from its campus, working alongside customers whose IT equipment generates the recoverable thermal energy.

Nearby, A2A is developing a dedicated Energy Center that will receive the exported heat.

From there, four industrial-scale heat pumps with a combined capacity of 72MW will raise the temperature of the recovered heat before feeding it into the district heating system.

The site will also house two thermal storage systems with a combined capacity of 6,000 cubic metres, together with the infrastructure needed to distribute the energy across the city.

When the project reaches full capacity, it is expected to recover as much as 225GWh of thermal energy every year.

According to Equinix and A2A, this will increase the heat delivered through Milan's district heating network by around 20%, providing sufficient energy to warm more than 21,000 homes.

Emanuela Grandi, Managing Director of Equinix Italy, says: “We are very proud of the efforts and achievements Equinix has done in blazing a trail for data centre heat export in Europe and we’re applying learnings from our successes to our efforts in Italy, helping create a market for data centre heat that can greatly contribute to the decarbonisation targets of the overall country.

“By scale, this initiative in Italy is expected to become among the largest data centre heat export project in Europe outside the Nordics.”

The ancient and the futuristic, side by side

Recovering waste heat is becoming an increasingly important part of the energy transition as operators seek new ways to improve efficiency while reducing dependence on conventional heating fuels.

Noah Nkonge, Heat Export Lead at Equinix, explains: “In a few words, we will create a process to capture and convert residual heat into a form suitable for other uses within the community.

“Heat export, rather than letting that heat go to waste, is a method for collecting and reusing it in communities near data centres, with the support of energy operators.

“By capturing and distributing heat generated in data centres, we will be creating a circular economy – reusing materials and products as much as possible to reduce waste and make the most efficient use of valuable resources, like electricity and heat," he adds.

Alongside the heat recovery infrastructure, the project extends A2A's district heating network, allowing low-carbon thermal energy to reach neighbourhoods across Milan, from the historic centre to surrounding districts.

Buildings already connected to the network include landmarks such as the Duomo and Palazzo Reale.

Italy's energy transition

Equinix and A2A estimate the project will prevent more than 345,000 tonnes of CO2 emissions while reducing the city's reliance on more conventional heating sources.

The companies also calculate that the emissions savings are comparable to the annual carbon absorption of approximately 220,000 trees.

“Data centres are strategic infrastructure for the competitiveness of the Country and for supporting the digital transformation of the economy," says Renato Mazzoncini, CEO of A2A.

“Their growth requires models capable of combining technological innovation, energy efficiency and environmental sustainability," he adds.

“From this perspective, heat recovery is a key lever for maximising the value of digital hubs and accelerating the decarbonisation of cities.

“The collaboration with Equinix is fully aligned with our strategy to develop an integrated ecosystem where energy, infrastructure and innovation operate synergistically.

“Through the investments outlined in the 2035 Plan and thanks to the Group’s industrial expertise, we intend to contribute to a strategic sector for Italy, while simultaneously generating economic, environmental and social value for local communities.”