Infomaniak Network SA from Les Acacias (GE) has won the Green Business Award in the SME / Corporates category with its D4 data centre. The fully underground data centre in Geneva uses all the heat generated by its servers and feeds it into the city’s district heating network. This can heat up to 6,000 homes in winter. D4 operates without conventional air conditioning or an external water supply.
This year, the Green Business Award is being presented in two categories for the first time. For business to become part of the solution, disruptive new technologies from scale-ups alone are not enough. SMEs and corporates must also transform their existing business models to create impact at scale. The Green Business Award recognises companies that are pioneering this transformation and helping to reshape entire industries. This year’s winner in the SME / Corporates category demonstrates what this can look like in practice by using the heat generated by its servers to supply heat to the local community.
From Energy Consumer to Energy Supplier
Servers continuously generate heat during operation. In conventional data centres, cooling systems are required to remove it. D4 instead uses this heat as an energy source for the surrounding area. Electricity first powers the servers, and the resulting heat is then fed into the district heating network. “With D4, digital infrastructure becomes part of the local energy supply. The heat is generated during operation anyway – Infomaniak makes it useful for the local population. It is a very tangible example of how an ecological challenge can be transformed into economic and societal value,” says Cédric Habermacher, Director of Green Business Switzerland.
D4 operates with three closed air and water circuits and therefore requires no external water supply
for cooling. Infomaniak feeds the heat into the district heating network and sells it at cost price for
20 years. According to calculations by the Enterprise for Society Center (E4S), when operating at full
capacity, D4 can avoid 3,600 tonnes of CO₂ equivalents per year compared with natural gas heating
and 5,500 tonnes compared with wood pellet heating.
The data centre’s complete documentation is available as open source at d4project.org. This enables
other companies and operators to access the concept and apply its technical approaches to
additional data centres.
“D4 addresses a central challenge of digital infrastructure in a compelling way: the heat generated during operation is fully recovered and fed into a public energy network. At the same time, Infomaniak makes the concept freely accessible. This combination of ecological impact, economic benefit and transferability convinced the jury,” says Doris Leuthard, former Federal Councillor and Chair of the Green Business Award jury.
Infomaniak Wins the Final
On 3 September, Infomaniak presented the D4 data centre to the main jury chaired by Doris Leuthard. The company prevailed over BELIMO Automation AG with its data-based optimisation solution RetroFIT+ and Vögeli AG Marketingproduktion & Druck with its circular printing and packaging solutions. The award was subsequently presented at the Maillot Vert Summer Party in Lucerne.
“This award sends a signal that, in the face of the environmental crisis and the AI boom, we need the courage to take new approaches. It confirms that data centres must not merely consume energy –they must serve society. D4’s real value lies in its replicability, and this award helps us achieve exactly that. We have made all the plans publicly available so that others can follow, and we thank everyone who believed in this necessary transformation,” says Boris Siegenthaler, founder and Chief Strategy Officer of Infomaniak Network SA.
AgroSustain, OceanSafe and Meteomatics are finalists in the Scale-up category. The winner will be
announced on 12 February 2027 at the Impact Circle Event in Gstaad.
Source : Green Business Award’s Press Release