Guide · Switzerland
Is an east–west PV system worthwhile?
In the morning, sunlight reaches one side of the roof; in the afternoon, the other. An east–west system follows that pattern. It does not need to look like a south-facing system on a graph to work well for your home.
Short answerShort answer
Is an east–west PV system worthwhile?
East–west usually reduces the midday peak but generates earlier and later. On flat roofs, denser coverage can offset part of the lower yield per module.
The midday peak is only part of the story
A high midday output looks impressive on a generation chart. In everyday use, the hours over which electricity is available matter too. East and west distribute generation differently. Whether you use more of it yourself depends on when appliances run and whether the car is actually at home to charge.
Compare the whole roof
On a pitched roof, the two sides are already defined. On a flat roof, the layout can also change how much capacity fits. Ask to see the complete layout rather than just a panel’s yield. A lower annual figure per kWp does not, by itself, tell you which complete installation will deliver more useful electricity.
The key considerations
Compare not only kWh per kWp but also per usable square metre and when that energy is self-consumed. A broader curve may be more valuable for a heat pump, home working or EV charging.
Official and specialist sources
- SFOE: photovoltaic market – 2025 price study
- ElCom: electricity tariffs 2026
- Pronovo: one-off payment calculator
- SwissEnergy: home battery storage
- SwissEnergy: self-consumption
- European Commission: PVGIS
- WattBilanz: Pronovo, exports, guarantees of origin and tax
Sources and price assumptions last checked on 18 September 2026.
Continue with your own data
Enter east and west as separate roof sections, then compare complete layouts with the same household demand.