Why batteries make sense here
Surplus solar is paid at roughly €0.04 to €0.06 per kWh, while the electricity you buy costs around €0.22. Every kWh you store and use yourself instead of exporting is worth four or five times more. In a home with evening cooking, air-conditioning at night in summer and a pool pump, a 10 kWh battery typically stores what a 5 to 6 kWp system has left over by mid-afternoon.
Batteries also give backup. Most hybrid inverters can keep a few circuits running through a cut, which matters on rural lines and in storms.
New system or retrofit
- New system: a hybrid inverter runs panels and battery together. Cleanest and cheapest.
- Adding to an existing system: either an AC-coupled battery that works alongside your current inverter, or a swap to a hybrid inverter. Budget €800 to €1,500 extra for the inverter route.
The FACTOR grant
The Balearic FACTOR 2026-27 programme pays households 45% of the battery cost, measured against a reference of €910 per kWh for systems up to 10 kWh (so a 10 kWh battery can bring back around €4,000). It opened on 9 July 2026 and closes on 28 February 2027, or earlier if the €4.1 million budget is used up. It's first-come, first-served, and you must be domiciled in the Balearics. Lead-acid batteries and systems without a 5-year manufacturer warranty don't qualify. The same programme pays 70% on a home EV charger (capped at €2,500). See the subsidies page.
Prices
Installed lithium batteries run about €480 to €700 per kWh: roughly €3,200 to €4,500 for 5 kWh, €5,000 to €7,000 for 10 kWh and €6,800 to €9,500 for 15 kWh. Prices have fallen for three years in a row.
Typical prices
| Job | Typical installed price | Notes |
|---|---|---|
| 5 kWh lithium battery | €3,200 to €4,500 | Flat or frugal home |
| 10 kWh lithium battery | €5,000 to €7,000 | Family home or villa; FACTOR pays 45% to residents |
| 15 kWh lithium battery | €6,800 to €9,500 | Villa with air-conditioning at night |
| Adding a battery to an existing system | + €800 to €1,500 | Hybrid inverter swap or AC-coupled unit |
incl. 21% IVA. Budget ranges from quotes across the island; real prices depend on a site visit.
What a good installer includes
- Usable capacity in kWh (not just nominal) and the warranty in cycles or years
- Backup capability and which circuits it covers
- Hybrid or AC-coupled design explained
- FACTOR application handled, with the installer's registration details
- Battery placed in a cool, ventilated spot away from living rooms
Watch out for
- A battery sized bigger than your evening use
- No 5-year manufacturer warranty (disqualifies the grant)
- Lead-acid at a lithium price
- Grant 'guaranteed' before the application is filed
Common questions
How big a battery do I need?
Roughly your evening and night consumption: 5 kWh for a frugal flat, 10 kWh for a family home, 15 kWh or more for a villa with air-conditioning at night.
Can I add a battery to my existing system?
Yes, either AC-coupled alongside your current inverter or by swapping to a hybrid inverter. Budget €800 to €1,500 more for the inverter route.
Does the battery grant cover non-residents?
No. FACTOR requires a Balearic domicile. Non-residents still benefit from the lower bills and the municipal IBI rebate.