The first energy renovation project of its kind in Switzerland

  • Switzerland’s largest Minergie-P® renovation project
  • Work completed = 98% of Minergie-P® surface areas under renovation in the Canton of Geneva
  • Pilot project subsidised by the Federal Office of Energy (OFEN)
  • 80% of heat generation through renewable energy
  • Energy reference surface area: 19,000 m²
  • Approximately 70% reduction in energy requirements after renovation
  • 1700m² of unglazed solar thermal panels
  • Innovative heating concept combining heat pump, ice accumulator and solar thermal roofing



Project summary

Created in 1952, ‘La Cigale’ is a housing cooperative comprising 273 apartments in two buildings located in Geneva, on the corner of the Rue de Vermont and the Rue du Vidollet. 57 years after the buildings’ construction and with the aim of preserving their asset, the members of the cooperative took the decision to renovate their two buildings.

In this context, Brolliet, which is responsible for managing the cooperative, and its partners, put forward a renovation solution which was both entirely innovative and exemplary in terms of energy savings. The objective was both clear and ambitious: to achieve a 70% reduction in the buildings’ heating requirements thanks to improved energy performance and less dependency on fossil fuels, with the aim of obtaining Minergie-P® certification. This solution comprised a highly efficient building envelope coupled with an innovative heating system combining heat pump, ice accumulator and solar thermal roofing.

Having quickly received unanimous validation from the members of La Cigale, this unique sustainable renovation project began in early 2013 and was completed the following year. Renovating two buildings dating back to the 50s, with the objective of obtaining Minergie-P® certification, proved to be a considerable challenge, one which was met with a great success, thanks to the commitment of all partners involved. In addition, the scale of the volumes handled in the context of this project makes it the largest Minergie-P® certified sustainable renovation project ever undertaken in Switzerland. It should also be noted that all the social, ecological and financial solutions that were implemented make it a pioneering experience, supported by the Federal Office of Energy, and fully reproducible.

Finally, in recognition of the innovation, commitment and sustainable solutions put in place, the La Cigale project received two prestigious awards:

  • The 2014 Canton of Geneva Award for Sustainable Development
  • The 2014 Swiss Solar Award