La Sosta Retirement Home – AEM

Municipal Retirement Home
Fondazione La Sosta is a municipal retirement home located in the city of Massagno in the southern part of Switzerland. Constructed in the 1970s, the building consists of 30 one- and two-room apartments arranged on 6 floors, a public space, a community centre, and an industrial kitchen. The building hosts approximately 30 elderly citizens offering assisted living services.


La Sosta has an existing all-electric infrastructure that provides space heating and domestic hot water to the entire building. In 2021, the building underwent some renovations, including the renewal of the roof insulation, the installation of a photovoltaic system and the replacement of the heating system.

In order to realise the goal of decarbonising heat production, while at the same time guaranteeing the current temperature standards in the building even during the coldest periods, the following devices were installed:

  • two air-water heat pumps on the roof of the building with a total output of 150 kWth and a water-to-water auxiliary HP (with an output of 150 kWth) located in the basement
  • a photovoltaic system built on the roof of the building with a capacity of 30 kWp, to partially power the thermal system.

The entire building can be classified as a vertical energy community, where each householder is recognized as a member, taking advantage of the local renewable energy production. Although further innovations seem necessary to further improve the building’s rating, no such activities are planned in the immediate future. As part of the EU co-funded research project ACCEPT, the installation of a wide range of sensors is planned for the year 2023.

AEM operates as the DSO of the area electricity network and as an ESCO as the owner of the PV plant on the rooftop and the heat pump system. It also acts as the energy community manager to which La Sosta belongs.


All residents are retired and receiving social services allowances. Most live alone and face health issues, so they are highly sensitive to the ambient conditions and environmental quality of their residence. The tenants are encouraged to maintain their autonomy and independence, while at the same time, the promoted lifestyle encourages strong social relations within this small community.