Solar panels in Île-de-France
The calculator opens on Paris. In Île-de-France sunshine varies little from one town to the next: it is the type of home that shapes the project.
Île-de-France produces a median of 1,147 kWh per kWp a year, slightly below the national median of 1,185, by our calculation on the European Commission’s PVGIS data. It is the region where output varies least: from 1,123 to 1,192 kWh from one commune to the next, a spread of about 6 %. Essonne leads with 1,160 kWh, thanks to the southern plains bordering the Beauce; Seine-Saint-Denis comes last at 1,137. Paris produces 1,140 kWh per kWp, about 27 % less than Marseille. For a household using 4,500 kWh a year with 3 kWp, payback is 18.0 years in Paris and 17.9 years in Évry. The real difference between two projects in the Paris region therefore comes from the home: a house with its own roof, a co-owned building where the roof is shared, or just a balcony.
Pays for itself in · 3 kWp in Paris
18.0 years
Net result over 20 years: +€665
| Output per year | 3,395 kWh |
| Used on site (47 %) | 1,605 kWh |
| Bill saving, year 1 | €321 |
| Surplus sold (1,790 kWh) | €20 |
| Standing-charge surcharge (export) | −€12 |
| Gain in year 1 | €329 |
| Share of your bill covered | 36 % |
| Price used (estimate) | €6,000 |
| Best-value size (estimated prices) | 2 kWc |
Month-by-month output in Paris (3 kWp)
December: 127 kWh; July: 403 kWh. PVGIS average 2005-2023.
Checked by Radif Partners · Editorial policy · Method and sources
The eight départements
| Département | Median kWh/kWp | Communes: from… to… | 3 kWp pays back in |
|---|---|---|---|
| Essonne (91) | 1,160 | 1,145 – 1,192 | 17.9 years |
| Seine-et-Marne (77) | 1,154 | 1,129 – 1,190 | 18.0 years |
| Hauts-de-Seine (92) | 1,145 | 1,140 – 1,149 | 18.0 years |
| Yvelines (78) | 1,141 | 1,123 – 1,187 | 18.0 years |
| Paris (75) | 1,140 | 1,140 – 1,140 | 18.0 years |
| Val-de-Marne (94) | 1,140 | 1,136 – 1,147 | 18.0 years |
| Val-d'Oise (95) | 1,139 | 1,123 – 1,145 | 18.0 years |
| Seine-Saint-Denis (93) | 1,137 | 1,136 – 1,140 | 18.0 years |
Paris and the inner suburbs form an almost uniform block, around 1,145 kWh per kWp. Differences appear in the outer ring: communes in the south of Essonne and Seine-et-Marne are the most productive, those in the Fontainebleau forest and the west of the Yvelines the least. In Versailles, output is 1,148 kWh per kWp.
The outer-suburb house
For a 4,500 kWh house at the Seine-et-Marne median, 3 kWp pays back in 18.0 years. For an 8,000 kWh household in Paris, the best 20-year size is 3 kWp; in Évry, 3 kWp. With surplus paid 1.1 c€/kWh, there is no point covering the whole roof. The mini-calculator below compares self-install kits.
Does a plug-in solar kit pay off where you live?
Pays for itself in
3.3 years
| Output per year, due south | 648 kWh |
| Saving per year | €129 |
| Average kit price found | €424 |
Household using 4,500 kWh a year, surplus not sold. Average prices found in January 2026, excluding mount and delivery.
Flats: the options
Without a roof of your own, the simplest route is a plug-in kit on a well-exposed balcony or terrace. For a house, start from a 3 kWp system and first check the town hall formalities, especially in protected areas.