Switzerland Introduces Winter Solar Bonus to Boost Photovoltaic Output

Switzerland has approved a winter solar bonus to expand photovoltaic capacity, particularly at alpine sites, and to support national renewable electricity targets. The measure aims to strengthen winter electricity production and accelerate the country’s solar energy expansion.

New Incentive for Winter Electricity Production

The Swiss government has introduced a winter solar bonus for photovoltaic installations. At the same time, it established new interim renewable electricity targets for 2030. Renewable sources excluding hydropower are expected to generate 35 TWh by 2035 and 45 TWh by 2050. Under the energy ordinance, the 2030 milestone is set at 23 TWh, with photovoltaics contributing 18.7 TWh and wind power 2.3 TWh, while the remainder will come from biomass, waste-to-energy, wood-fired plants, and geothermal sources where available.

Winter Solar Bonus for Large PV Installations

The incentive applies to new photovoltaic systems of 100 kW or more commissioned from 1 January 2026 onward. The bonus replaces an earlier elevation-based support mechanism and is intended to improve winter electricity production, especially at alpine sites with favorable seasonal yield patterns. A forthcoming ordinance will detail how the bonus integrates into existing support mechanisms such as market premiums, auctions, and one-off payments.

Photovoltaic Output Must More Than Double by 2030

Current forecasts suggest that reaching the 2030 photovoltaic target of 18.7 TWh will require more than doubling the expected 2025 output of just over 8 TWh. This will necessitate a significant expansion of annual installation capacity—up to around 2.7 GW over the next five years. After a record installation year in 2024, a market slowdown to around 1.6 GW is projected for 2025.

Industry Assessments and Market Potential

Analysts maintain that the sector can manage the required average annual growth of 11%, noting past growth rates far exceeded this threshold. Most expansion will continue to occur on rooftops, where only a small portion of the potential has been tapped so far. Installations on façades, infrastructure, agricultural land, and alpine terrain are also growing steadily, and suitable surface area is not considered a limiting factor.

Winter Targets and Grid Reliability

By 2030, approximately 5 TWh of solar output is expected during the winter period, roughly matching the country’s maximum allowable electricity imports. This equals about 15% of winter consumption. For comparison, priority hydropower projects aim to supply up to 2 TWh of additional winter electricity by 2040.

The winter solar bonus is expected to increase the seasonal contribution of new PV installations, and the absence of a cap on support for alpine systems has been viewed positively by industry observers.