Solar payback calculator for Portugal

Last updated 29 October 2026

Enter your own numbers. The defaults reflect typical 2026 values for a 3.5 kWp system in central Portugal. The single most important input is the share you use yourself — read why self-consumption is everything.

Estimated production: – kWh/year

Estimated yearly benefit: –

Simple payback: –

–

Assumptions

  • Yearly yield per kWp by region is a rough average for a well-oriented, unshaded roof; your installer's simulation is more precise.
  • 3% system losses; 0.5% panel degradation per year; prices held flat.
  • No subsidies (none are open as of October 2026) and 23% VAT included in the price you enter.
  • Battery systems: raise the self-consumption share and the price accordingly.