ExerGo provides the the world’s first CO₂-based energy network. Harnessing renewable resources and waste heat, the company uses CO₂ as a heat transfer fluid in a closed loop instead of water as in incumbent networks. Using CO₂ and its phase change between liquid and vapor, the network is up to nine times denser, allowing the use of smaller, flexible pipes. At its pilot plant in Sion, Switzerland, ExerGo sources clean energy from underground water. Through existing heat pumps and exchangers, it delivers 1200 MWh heating and cooling per year, all-year round, since March 2022. Allowing heat and cold to flow bidirectionally, the network leverages surplus heat, which optimises heating and cooling needs between users of the three multi-storey buildings of the Energypolis Campus of HES-SO University of Applied sciences.