Selling solar surplus to the grid in Portugal (2026)
Resposta rápida
Self-consumption vs selling surplus
There are two ways to use what you produce: use it on the spot (self-consumption) or export it to the grid and get it credited on your bill (surplus sale). The value gap is huge:
- Self-consumption: each kWh is worth what you'd otherwise pay — about €0.22/kWh.
- Exported surplus: each kWh is typically worth €0.04 to €0.10/kWh.
So the goal of good sizing is to maximise self-consumption — and only sell what genuinely is left over.
What an exported kWh is worth
In most contracts, the surplus price is indexed to the wholesale market (OMIE), so it varies through the year. Some suppliers offer a fixed value, others indexed. Always compare both the buy and sell tariff when choosing.
What you need to sell
- A smart meter (E-Redes installs or updates yours).
- UPAC (self-consumption unit) registration with the DGEG.
- A surplus purchase contract with a supplier.
We handle the process
So, is it worth selling?
It's worth using the surplus (better to be paid for it than waste it), but not worth oversizing the system just to sell — the return is in self-consumption. If you have a lot of surplus, consider a battery to use that energy at night instead.
Not sure what size is right for you? Run the simulator to find the power that maximises self-consumption.
Frequently asked questions
Can I sell the solar energy I don't use?
Yes. The energy you produce but don't consume can be exported to the grid and sold to your electricity supplier through a surplus sale contract. You need a smart meter and a self-consumption (UPAC) registration with the DGEG.
How much do you get per kWh sold to the grid?
It's typically low and indexed to the wholesale market (OMIE) — around €0.04 to €0.10/kWh depending on the supplier and month, well below the ~€0.22/kWh you pay to buy. So it almost always pays more to self-consume than to sell.
What do I need to sell surplus?
A smart meter (E-Redes installs/updates it), the self-consumption unit (UPAC) registration with the DGEG, and a surplus purchase contract with a supplier. Bave Energy handles the technical side and the registration.
Is it better to sell or self-consume?
Self-consume. Each kWh you use directly is worth what you'd pay the grid (~€0.22), while exported energy is worth much less. The ideal is to size the system to maximise self-consumption and only sell the leftover surplus.