Large-scale photovoltaic systems
There were only a few large ground-mounted photovoltaic systems in Switzerland as of 2023. Installations have thus far been built almost exclusively on or attached to existing buildings. SFOE studies show that in Switzerland, free-standing plants hold the greatest potential.
On 30 September 2022, Parliament adopted urgent measures to ensure a secure electricity supply in winter in the short term, which created the framework for a time- and volume-limited expansion of large-scale photovoltaic systems outside building zones (see Infobox 2). The plants must generate a significant proportion of winter electricity if they are to benefit from the simplified authorisation process and preferential support.
Legislative framework
On 30 September 2022, Parliament introduced the framework for a streamlined authorisation process for large-scale photovoltaic systems with Article 71a of the Energy Act. The following criteria must be met:
- Minimum size (annual production of at least 10 GWh)
- Minimum electricity production during the winter half-year (at least 500 kWh/kW)
- The planning application must be made available for public inspection by 31 December 2025
If these criteria are met, the plants are deemed to be site-specific and of national interest, and their realisation generally takes precedence over other interests. Furthermore, there is no planning requirement for such facilities, meaning that neither a structure plan nor a land-use plan needs to be established. However, an environmental impact assessment is still required, and the facilities must be completely dismantled following decommissioning.
This provision shall apply until the cumulative expected annual output of plants with final authorisation reaches 2 TWh.
Depending on their location and orientation, high-altitude photovoltaic systems can generate more electricity per kilowatt of installed capacity in winter than comparable systems on the Swiss Plateau. This is because the radiation conditions are better (thinner atmosphere, less fog) and because the sunlight is reflected by the snow (known as the albedo effect). Test plant measurements and yield simulations indicate that annual production will be around 50% higher, and the specific winter yield 2 to 3 times higher, than for plants on the Swiss Plateau.
However, to date there has been almost no experience with large-scale photovoltaic systems in high mountain regions. Increased snow and wind loads place particular demands on anchoring systems and substructures, accessing the site for construction and grid connection can be challenging, and conflicts may arise with nature conservation and landscape protection. For these reasons, alpine photovoltaic systems are often significantly more expensive than large-scale plants on the Swiss Plateau.
Comparison of photovoltaic systems' monthly energy yield
Where are large-scale photovoltaic systems located in Switzerland?
This interactive map shows where in Switzerland large-scale photovoltaic systems under Article 71a of the Energy Act are planned or have already been built, their capacity and how much electricity they are expected to produce or actually produce. The map is updated regularly.
Click here for the interactive map