Guest Commentary: Solar Power Misunderstood and Undermined by Subsidies?

Switzerland’s solar boom has reached a point where, during some hours, photovoltaic production already exceeds the country’s total electricity demand. Yet the national energy strategy still calls for solar capacity to quadruple. That contradiction is fueling doubts about how the strategy is being implemented.

Photovoltaic systems are now Switzerland’s fastest-growing electricity source, including during the winter half of the year. New rooftop installations built in 2024 alone are expected to generate around 400 gigawatt-hours of winter electricity. That is roughly equivalent to the energy volume ElCom defines, on average, as a winter hydropower reserve.

The additional solar power could help leave reservoirs with about 400 GWh more energy available in spring, whether a winter brings prolonged snowfall or periods of low wind and low solar output. Energy trading can produce different results in practice, the commentary notes, but over the year the sun remains Switzerland’s most reliable energy source.

Solar power now ranks third among the country’s main electricity sources, behind hydropower and nuclear power. With more than 10 GW of installed capacity, Switzerland’s photovoltaic systems already form the country’s most powerful generating facility when treated as a single, largely sun-driven system. Their combined capacity is about three times that of all Swiss nuclear plants.

The problem is that most of the roughly 400,000 installations feed electricity into the grid without output control. The resulting surges are not easy conditions for the planned expansion. Solar power, the commentary argues, can no longer remain an untouchable symbol of hope with priority access to the grid and exemption from requirements for network and system stability. Major distribution-grid operators and the Association of Swiss Electricity Companies reportedly say rooftop photovoltaics are making grid expansion a major issue. The policy sequence, from subsidies to mandatory installation and then possible charges for feeding power into the grid from 2027, has only sharpened the criticism.