cannot absorb the recovered energy), the system switches to direct free cooling using filtered outside air— with no active cold production involved.
At the heart of the energy recovery system are two Trane RTWF heat pumps, which raise the temperature or recycled low-grade server-heat from 45 ° C to 67 ° C in summer and up to 85 ° C in winter. This temperature range is required to match the specifications of the local district heating operator( Geneva’ s Industrial Services- SIG).
Prior to installation at the site, the Trane heat pumps have been tested and performance-validated under rigorous laboratory conditions at Trane’ s state-of-the art laboratory in Charmes, France. This testing confirmed their ability to deliver consistent performance even in demanding operating environments.
Environmental Integration and Future-Ready Design The Infomaniak data centre facility not only showcases energy recovery and reuse but also encourages a shift in how data centre efficiency is measured. In addition to Power Usage Effectiveness( PUE), the company advocates for Energy Reuse Effectiveness( ERE) and Energy Reuse Factor( ERF), which account how much energy is reused outside the facility.
Infomaniak’ s founder and strategic director Boris Siegenthaler emphasizes:“ Today, PUE is no longer sufficient in the face of the climate emergency. We must also consider ERE and ERF, which provide a more
This project marks a key step in the regional energy transition, transforming a traditionally energyintensive facility into an active example of circular energy use.
complete picture of how effectively energy is reused, for example to supply heat to which evaluates the energy actually consumed compared to that reused, and ERF, which measures the share of the total energy of the data centre reused for other uses, such as district heating. Together, these three indicators provide a more complete picture of true energy efficiency of digital infrastructures.”
Recognition and Impact The Geneva facility is aligned with national and regional sustainability policies aimed at reducing reliance on fossil fuels and increasing renewable energy integration. The project has received multiple accoladed, including the Swiss Ethics Prize and the Cantonal Sustainable Development Prize, acknowledging its contribution to climate mitigation and responsible innovation.
Currently operating at 25 % capacity, the data centre is expected to reach full operational capacity by 2028 and continue its heat supply for at least two decades.
Trane’ s Role in Energy Transition Trane’ s high-temperature and highefficiency heat pump technology is a key enabler of this transformation. Its application in Geneva demonstrates how even energyintensive data centre facilities can become contributors to clean, circular energy systems.
Lauri Salmia, Applied Portfolio Manager at Trane summarises:“ With the exponential growth of cloud services, the volume of waste heat generated by data centres is increasing rapidly. This energy must be reused rather than lost. Leveraging existing technology, connecting these installations to district heating networks, and designing them with thermal recovery in mind, is essential. The Infomaniak site in Geneva demonstrates a model that can influence cloud infrastructure developments worldwide, proving that performance and sustainability can go hand in hand.”
Infomaniak Data Centre- Key figures
• Total area: 1,800 m2.
• Full server capacity: approx. 10,000 servers( 200 x 47U racks).
• Average thermal energy output: 14.9GWh( 1.7MW)
• Average PUE: 1.09( EU average: 1.6).
• ERE and ERF: see online
• Heat pump system: 2 x Trane XStream™ RTWF with a total capacity of 3.2 MW.
• Linked solar power plant capacity: 130 kWp( 364 modules).
Issue 76 PECM 31