All new buildings with large roofs must have solar panels installed. The law will apply to all new builds with a roof space of more than 300 m2.
But parliament has rejected a campaign to also include renovations and is still discussing solar panels for parking spaces.
The move comes after voters in canton Valais rejected building solar farms in the Alps.
Commentators suggested the people wanted buildings to be prioritized for solar panels before installing them in the mountains.
Montreux rock legend honoured
Montreux turned into a giant Freddie Mercury tribute this weekend, as the town marked what would have been the Queen singer's 80th birthday last Friday
Station preview in Lausanne
Hundreds of Lausanne residents got a rare look inside the giant rebuild of the city's main station this weekend
New historic attraction in Geneva
Geneva has opened a new underground archaeological site displaying nearly 2,000 years of the city's history
Summer weather only getting hotter
Roughly one summer in two will be hotter than 2026, according to an ETH Zurich climatologist
New global accord close to being finalised
After a decade of talks, 128 countries have reached the first global accord on autonomous weapons in Geneva
Neutrality debate heats up
Switzerland's 27 September vote on tightening neutrality is splitting the political left three weeks out from polling day
