Solar energy: The solar potential of all roofs in Switzerland – a climate-related service

The interactive application sonnendach.ch shows users anywhere in Switzerland how well suited their building is for producing energy. sonnendach.ch was set up as part of the Swiss government’s Energy Strategy 2050, as a joint project between the Federal Office of Energy, the Federal Office of Meteorology and Climatology (MeteoSwiss) and the Federal Office of Topography (swisstopo). For the purposes of the project, the company Meteotest collated all of the baseline data from the three Federal Offices and worked out the solar potential from these to provide a free climate-related service.

The solar potential of house roofs in Locarno (red: high potential; yellow/orange: medium potential; blue: low potential). Geodata © BFE, swisstopo, MeteoSwiss

After existing solar potential analyses were tested for their usefulness, the project  developed a new user friendly approach from scratch. sonnendach.ch enables interested members of the public to estimate their solar potential with one or two mouse clicks. Even those living in smaller communities will thus be able to get an estimate of the solar potential of their roof or facade.

The MeteoSwiss contribution

MeteoSwiss is participating in the project through its climate services in the context of the National Centre for Climate Services (NCCS). Our spatial data on incoming solar radiation differ according to the position of the sun, cloud cover and region. To estimate the local solar radiation, satellite measurements are used from the “METEOSAT Second Generation” geostationary earth-observation satellite. Satellite data are ideal for supplementing the ground-based measurements, as they supply information that fills the gaps in the ground-based data have gaps (see figure 2). The calculation method was developed and tested over several years in a collaborative research project in the context of the EUMETSAT Satellite Application Facility on Climate Monitoring (CM SAF) with a focus on the complex topography of the Alps.

Annual deviation of global radiation from the long term mean for 2017 in W/m2, derived from satellite measurements. Central Switzerland and Ticino enjoyed above-average solar radiation in 2017. The circles represent the measurements taken by the monitoring stations.

The Swiss government’s Energy Strategy 2050 stipulates that there should be a greater use of renewable forms of energy. The use of such energy is heavily dependent on weather and climate. MeteoSwiss therefore plays an important part in the efficient implementation of the energy strategy, thanks to its meteorological and climatological data and Expertise.

Links

• Solar energy potential of all roofs in Switzerland
• Solar energy at MeteoSwiss
• 3D data of roof area by the Swiss Federal Office of Topography swisstopo
• Solar cadastre of Switzerland by Meteotest

Last modification 18.07.2022