With an average of 40.8 kWp per system, the Canton of Zug has the largest solar systems in the whole of Switzerland – well above the Swiss average of 26.1 kWp. In total, around 124.7 megawatts are installed across 3,056 systems. New systems are reported to the municipality as a building notification, with a 20-day notice period from the submission of complete documents. (As of: SFOE register data August 2026, Swissolar annual figures 2025)
Key points in brief
- Average system size 40.8 kWp – the highest value of all 26 cantons.
- 124.7 MW installed capacity across around 3,056 systems; per capita around 924 watts (rank 18 out of 26).
- In-roof proportion 7.3%, below the Swiss average of 12.7%.
- Notification procedure: building notification to the municipal building department, 20 days from complete documents.
Why does Zug have the largest solar systems in Switzerland?
With an average of 40.8 kWp per system, the Canton of Zug tops the SFOE installation register for all 26 cantons – well ahead of the Swiss average of 26.1 kWp. The register itself provides no reason for this, but an obvious explanation is the economic structure of the canton: a high proportion of commercial and corporate headquarters with large, continuous roof areas can significantly raise the statistical average compared to purely residential cantons.
| Metric | Value (Canton of Zug) | Switzerland overall (comparison) |
|---|---|---|
| Installed capacity | 124.7 MW | 8,635 MW (register) / 9,498.6 MW (Swissolar) |
| Number of systems | 3’056 | 331,271 (register) / 338,270 (Swissolar) |
| Per-capita capacity | 924 W/inhabitant | 946 W/resident (Swiss average) |
| Per-capita density rank | 18 out of 26 | — |
| Average system size | 40.8 kWp (highest value in Switzerland) | 26.1 kWp |
| Roof-integrated share | 7,3 % | 12,7 % |
Source: SFOE plant register (register status August 2026); national comparison values from Swissolar's «Solar energy statistics 2025».
What are the procedural rules in the Canton of Zug?
In the Canton of Zug, a solar system is reported to the municipal building department as a building notification (§ 44a PBG), with a notice period of 20 days from the submission of complete documents. An important note for facade projects: The official cantonal leaflet on the notification procedure dates from May 2024 and still treats facade systems under old law – since 1 January 2026, the simplified notification procedure also applies to facades under federal law. For facade projects, it is therefore worth taking a look at the current federal regulations as well, rather than just the older municipal leaflet.
The high average system size in the Canton of Zug is consistent with our experience from larger commercial projects in the region: where a business has a large, continuous roof, it is often fully utilised in Zug, rather than just occupying a part.
Frequently asked questions
Why are solar systems in the Canton of Zug so much larger on average than elsewhere?
The statistics only show the result (40.8 kWp on average, the highest value in Switzerland), not an officially confirmed cause. A plausible factor is the high density of commercial and corporate locations with large roof areas.
Does the Zug notification procedure leaflet also apply to facade systems?
The municipal leaflet (as of May 2024) is outdated for facades. Since 1 January 2026, the simplified notification procedure also applies to facades under federal law – this newer regulation is decisive.
Is Zug a progressive canton when it comes to photovoltaics?
In terms of per capita density, Zug is in the middle (rank 18 out of 26). In terms of average system size, however, it is clearly at the top in Switzerland.
How current are these figures?
Structural data as of August 2026 (SFOE register), national comparison values from Swissolar's 2025 annual statistics.
Large commercial roof in the Canton of Zug?
We plan solar systems for commercial and corporate locations in the Canton of Zug – from the feasibility study to commissioning.
Sources: SFOE installation register (register status August 2026), Swissolar «Statistik Sonnenenergie 2025», cantonal leaflet Zug (as of May 2024).
Last updated: 18 September 2026 · Contact for questions on methodology: ecoEn editorial team
