When your panels produce more than you are using at that moment, the extra goes out to the grid. That is your surplus (excedentes), and in Spain it can be taken off your electricity bill.
How simplified compensation works
It is the scheme almost all homes with solar use, regulated by Royal Decree 244/2019:
- Your meter records, hour by hour, the energy you take from the grid and the energy you export.
- Each month your supplier values your surplus and deducts that amount from the energy part of your bill.
- It applies to renewable systems of up to 100 kW with a compensation agreement with your supplier.
How much you get per kWh
It depends on your tariff:
- On the regulated tariff (PVPC), surplus is valued at the wholesale market price for each hour. Around midday on sunny days that price is often low.
- On a free-market tariff, the compensation price is set in your contract. Some offers are designed for solar owners, with higher compensation prices or a virtual battery.
Either way, an exported kWh is worth much less than a kWh you buy. That is why using your own energy as it is produced always saves more than exporting it.
The limit: your bill never goes below zero
Compensation has two important caps:
- It is only deducted from the energy charge. Contracted power, meter rental and taxes are still paid.
- If one month you produce far more than you use, the uncompensated surplus is lost, unless your supplier offers a virtual battery.
So oversizing a system without a battery rarely pays off.
Can I actually sell electricity for cash?
Not under simplified compensation: you get a discount on your bill, not money. Selling energy for cash means registering as a producer, with extra paperwork and tax obligations. For a home it is rarely worth it.
How to get more out of it
- Shift loads to sunny hours: washing machine, dishwasher, water heater, pool pump, car charging.
- Choose your tariff carefully: compare the compensation price as well as the price of electricity.
- Consider a battery if your surplus is very large. See is a solar battery worth it in Spain?.
Is there any paperwork?
Yes. The system has to be legalised and registered as self-consumption with surplus under compensation. The installer usually handles the registration with the Junta de Andalucía, and the distribution company passes the data to your supplier. Until that is done, your surplus is not credited, so it is worth not delaying it. More in solar panels and Spanish law.
Want to know how much surplus you would have? Send us your bill through the bill check. We reply in English.