Declaring a plug in solar kit in France and Belgium
In France every kit is declared to Enedis, even without feed in. In Belgium the inverter must be on the Synergrid list and each region has its own rule.
Last checked on 8 November 2026
France: the CACSI with Enedis
In France every self consumption installation must be declared to Enedis, whatever its power and even if it never feeds electricity into the grid. Since 15 September 2025 this is done with the CACSI agreement, free of charge, through Enedis Connect. We have found no official power limit for plug in kits. The market uses 800 W, and the 3 kW often quoted comes from a threshold in the Energy Code for tolerated free surplus, not from a rule for plug in kits.
The self consumption premium and the reduced VAT rate apply to professionally installed systems with a surplus contract, not to kits you install yourself.
Note what the CACSI means: by signing it you commit not to feed electricity into the grid. A kit on a socket can still push out a small surplus at midday, so size it to your daytime use. If you want to sell surplus, a different connection procedure applies.
Belgium: the Synergrid list and the regions
Plug and play sets have been legal in Belgium since 17 April 2025, after a change to Synergrid's C10/11 rules. Only the inverter must appear on the C10/26 list, which is updated weekly. The limit is 800 W per household, batteries included. Notification differs by region: in Wallonia you notify the distribution operator with form UP10, in Brussels you notify Sibelga, and in Flanders no notification is required below 800 W. Check the current rule with your operator, because these details change.
Before you buy
In Belgium, look up the exact inverter or battery model on the Synergrid list before you order. In France, prepare the data sheet of the inverter for the Enedis form. In both countries, keep the total power within 800 W, and read your home insurance conditions for anything about self installed electrical equipment.
What 800 W produces in Paris, Lyon and Brussels
The same calculation as our calculator, with PVGIS data, for an 800 Wp system in three cities: south at 35 degrees, south vertical on a railing and west vertical. In France nothing is paid for surplus fed to the grid under the self consumption agreement, so the own use column is what counts.
| City | Panels | South, 35° | South, vertical | West, vertical | Own use and savings (south, vertical) |
|---|---|---|---|---|---|
| Paris | 800 Wp | 887 kWh | 633 kWh | 436 kWh | 407 kWh, €101.65 |
| Lyon | 800 Wp | 988 kWh | 685 kWh | 480 kWh | 420 kWh, €104.95 |
| Brussels | 800 Wp | 807 kWh | 583 kWh | 404 kWh | 393 kWh, €129.53 |