Solar panels in Spain
A 6 kWp system on a typical roof in Spain generates 9,414 kWh a year, worth €979 in the first year against €6,480 spent up front. Everything below shows how that is worked out, on real climate data and this year's actual tariffs.
Where the money comes from
9,320 kWh in year oneEvery kilowatt-hour your roof makes is worth one of two very different amounts. Power you use as it is generated replaces power you would have bought, so it is worth the full retail price. Power you do not use goes to the grid at the export rate, which is far lower. The balance between those two is what actually decides whether solar pays here.
- Used in the house
- 2,796 kWh (30% of output) at 0.210 EUR/kWh, the retail price you avoid paying.
- Sold to the grid
- 6,524 kWh (70% of output) at 0.060 EUR/kWh, the export rate your supplier pays.
Averaged out, each kilowatt-hour is worth 0.105 EUR/kWh. That blended figure, not the headline retail price, is what drives every number on this page. Using more of your own power (an EV, a heat pump, a battery, or simply running appliances by day) shifts output from the lavender side to the mint side and raises it.
A year on the roof
1,569 kWh per kWp · PVGIS-SARAH3Output is not spread evenly. July is the strongest month at 972 kWh, 1.7× what December manages at 580 kWh. Annual totals hide that swing, which is why a system sized purely on your yearly bill tends to overshoot in summer and undershoot in winter.
The 25-year picture
- Everything the system saves and earns
- €24,524
- What you pay up front
- − €6,480
- Left over
- €18,044
25 years of avoided bills plus export payments, after maintenance and one inverter replacement.
Install cost after €720 of grant.
Straight subtraction, ignoring the fact that money arriving 25 years from now is worth less than money today.
Same result, in today's money
€8,541€18,044 spread over 25 years is not worth €18,044 today, because you could have done something else with the money in the meantime. Discounting future savings at 4% a year gives €8,541, the net present value. It is the honest number to compare against another investment, and the equivalent annual return is 13.9%.
On the same discounted basis the system pays for itself after 8.3 years.
When you break even
Your position starts at minus €6,480 on install day and climbs as the system earns. The line crossing zero is the payback point.
Cumulative cash position
Break-even in year 7Net position after each year (−net capex up front, then cumulative savings). Crossing the dashed line is payback.
How that figure is built
No step here is a rule of thumb. Every one of them is the same code path the calculator runs on your own address.
Start with the weather, not a brochure
PVGIS-SARAH3 holds satellite-measured irradiance for this location. For a 6 kWp array at 35° facing south it works out to 1,569 kWh per kWp per year. That is the number a brochure would round up.
Scale it to the system
6 kWp × 1,569 kWh/kWp = 9,414 kWh a year. Panels lose about 1% in year one and 0.4% a year after, so year one is modelled at 9,320 kWh.
Price each kilowatt-hour twice
30% is used in the house at 0.210 EUR/kWh, the rest exported at 0.060 EUR/kWh. Together: €979 in year one.
Subtract what you actually hand over
A 6 kWp install in Spain runs about €7,200, less €720 of grant, so €6,480 out of pocket.
Run it for 25 years, honestly
Electricity prices rise 2% a year, panels keep degrading, maintenance costs about 1% of the system price annually, and the inverter gets replaced once. Total savings come to €24,524, clearing the upfront cost after 7.0 years.
What we assumed for Spain
Change any of these and the answer changes. They are published so you can check them against your own bill and your own quote.
| System size modelled | 6 kWp at 35° facing south |
| Install cost before any grant | €7,200 |
| Grant or incentive | 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) |
| Net cost to you | €6,480 |
| Electricity price you avoid paying | 0.210 EUR/kWh |
| Export rate paid to you | 0.060 EUR/kWh |
| Share used in the house | 30% of output |
| Electricity price inflation | 2% a year |
| Panel degradation | 1% in year one, then 0.4% a year |
| Maintenance | 1% of system cost a year, plus one inverter replacement |
| Discount rate for present value | 4% a year, real |
| CO₂ avoided | 2,664 kg a year · 62,868 kg over 25 years |
Estimate only, not a quote. Tariffs and grants change; figures use the rates on file for 2026 and an installer's survey will produce the exact number.
Questions people ask about solar in Spain
- Is solar worth it in Spain?
- A 6 kWp system in Spain pays for itself in about 7.0 years and returns €24,524 of savings over 25 years against €6,480 spent up front. Your roof, orientation and shading move the result, which is what the calculator works out for your exact address.
- How much do solar panels cost in Spain?
- About €7,200 for a 6 kWp install, less €720 of grant, so €6,480 out of pocket. Installers quote against your specific roof, so treat this as the middle of the range.
- What do you get paid for exporting solar power in Spain?
- Exports are modelled at 0.060 EUR/kWh against a retail import price of 0.210 EUR/kWh. Because exporting is worth much less than using the power yourself, how much you consume during daylight matters more than the size of the array.
Your roof is not the average roof
Orientation, pitch, shading and how much power you use by day move these numbers more than anything on this page. The calculator runs the same model on your actual address.
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Solar by city in Spain
Same model, run on each city's own climate data.
For the incentives, tariffs and the 2026 rule changes in detail, read our Spain solar guide.