Solar panels in Barcelona

Modelled output of a 6 kWp system at 35° facing south (towards the equator), from PVGIS climate data (PVGIS-SARAH3, 2005 to 2023).

• Best month: July (942 kWh). Weakest: November (558 kWh), a 1.7x difference.
• May, June, July produce 30.5% of the year; January, November, December produce 19.2%.
• Year-to-year variation: about 252 kWh (2.8%, one standard deviation).
• Sunlight reaching the panels: 1,974 kWh per m² a year.

Rules set by the city or its region, on top of the national scheme. Each one was checked against the official source on the date shown.

• City of Barcelona

  IBI rebate for solar panels

  Barcelona's property tax (IBI) ordinance gives a 50% rebate for residential and tertiary buildings (30% for industrial) with solar systems, for up to three tax years after the self-consumption registration (RAC) request. The request must be filed within 12 months of that registration request (three years if within 6 months, two years if later), and the total rebate cannot exceed the installation cost.

  Source: Ajuntament de Barcelona, Institut Municipal d'Hisenda, Ordenança fiscal núm. 1.1 reguladora de l'impost sobre béns immobles (BOPB 23-12-2024) (checked 2026-09-25)

• City of Barcelona

  ICIO construction tax rebate for solar

  Barcelona's construction tax (ICIO) ordinance published in February 2026 gives a 95% rebate for works that add solar thermal or PV systems, provided the installation is not legally mandatory. The rebate must be requested before works start.

  Source: Ajuntament de Barcelona, Institut Municipal d'Hisenda, Ordenança fiscal 2.1 de l'impost sobre construccions, instal·lacions i obres (BOPB 2-2-2026) (checked 2026-09-25)

Barcelona ranks 4 of 4 for yield among the cities we model in Spain, and 9 of 41 across every country on Solar Figures. Within one country the prices are the same, so a payback gap between these cities comes from sunshine alone.

Closest yield abroad: Sydney (1,502 kWh per kWp), Brisbane (1,469 kWh per kWp), Delhi (1,552 kWh per kWp).

Power you use yourself is worth the retail price (€0.21 per kWh); power you export earns €0.06. So the share you use at home, by running appliances in daylight or adding a battery, changes the payback. The system cost stays the same in every row (a battery would add to it).

• Net system cost after incentives: €6,480 for 6 kWp.
• Incentive modelled: €720 (IRPF energy-efficiency deduction, modelled at a conservative 10% (the 40% band, base max 7,500 EUR, applies only with an A/B energy rating or >=30% non-renewable primary-energy cut)).
• 25-year net savings at our default: €23,462.

At latitude 41.39°N, PVGIS finds the fixed tilt and direction that maximise yearly output. Our figures use a common 35° roof; the table shows what the optimum adds.

The optimum adds 0.1% a year over the standard roof in Barcelona. Most of a roof's value comes from its direction: a roof facing away from the equator loses far more than a few degrees of tilt.