On its websites www.sonnendach.ch and www.sonnenfassade.ch, the Swiss Federal Office of Energy SFOE shows which types of building surfaces are suitable for generating solar energy. This is the result: Switzerland’s roofs and facades have an annual solar power production potential of 67 terawatt-hours (TWh) (Press release SFOE 15.4.2019, in German, French, and Italian). This exceeds Switzerland’s current power consumption by over 10 percent!
An in-depth analysis including photovoltaics’ potential on roads, highway embankments and open alpine spaces can be found here: The Swiss PV potential based on individual buildings. Meteotest/Swissolar 2019 (PDF, in German)
Some of the available rooftop and facade surfaces can also be used for solar collectors to produce heat. In an earlier study (2017), Meteotest stated that this potential amounts to 11 TWh, which is about 10% of Switzerland’s current heating requirements. If the demand were reduced by implementing adequate isolation, solar thermal could even cover 20% of our needs.
The federal energy scenarios do not yet take fully into account all the potentials and the rapid decrease of solar energy costs. According to the 2013 Federal Council Dispatch (in German), photovoltaics will produce only 11.1 TWh of electricity per year by 2050. This is in sharp contradiction to the elimination of fossil and nuclear energies that will be required by then. Calculations made by Roger Nordmann, President of Swissolar and National Councillor, have revealed that we need to install 50 GW of photovoltaic power until 2050, producing 45 TWh every year, in order to compensate the dismantled nuclear power and to cover the additional demand of electromobility and heat pumps. This is assuming that Switzerland’s power supply will remain independent of electricity imports in the annual balance. We have enough buildings to install this PV power without needing any additional surfaces.
Roger Nordmanns’ book «Sonne für den Klimaschutz» («Solar for climate protection») is available in French and in German and can be ordered via our webshop.