A physical battery stores electricity at the property. A virtual battery is a tariff mechanism that records the financial value of exported energy. They solve different problems.
Reviewed August 2026
QUICK ANSWER
Is a physical or virtual battery better for a Spanish property?
Choose according to the problem. A physical battery can move stored electricity into the evening and may support selected circuits with compatible backup equipment. A virtual battery stores value with an electricity supplier and can reduce later bills, but it does not power the home during an outage.
What a physical battery changes
A home battery receives compatible solar surplus and releases stored electricity when the property would otherwise import from the grid. Its useful capacity, power output and cycling pattern matter more than the headline size.
Backup is a separate capability. The inverter, switching equipment and supported circuits must be designed for an outage. A battery connected only for self-consumption does not automatically keep the home running when the grid fails.
What a virtual battery actually stores
A virtual battery does not retain electricity at the property. The supplier assigns a financial value to exported surplus under its tariff rules and carries that balance forward in the way described by the contract.
Terms can change between suppliers. Check export rates, monthly fees, balance expiry, whether credit can offset every part of the bill and whether more than one supply can use the balance.
Holiday homes need a different calculation
A lightly occupied property may export for long periods and have little evening demand to cycle a physical battery. A well-suited virtual arrangement can make that surplus more useful, subject to the supplier's terms.
A villa with security, refrigeration and regular evening occupation may still benefit from physical storage. If outage support matters, a virtual balance cannot provide it.
The two options can work together
A property can use a physical battery to cover part of its evening demand and still export energy once that battery is full. The remaining surplus may then be compensated under the supply contract.
The solar array should not be oversized on the assumption that every exported unit will retain the same value indefinitely. System design and tariff selection need reviewing together.
Does a virtual battery provide electricity at night?+
No. The home imports electricity from the grid as normal. The virtual balance may reduce the financial value of the bill under the supplier's rules.
Can a physical battery work during a blackout?+
Only with a compatible backup design and configured circuits. Storage alone does not guarantee outage operation.
Can I have both a physical and virtual battery?+
Potentially. Surplus remaining after the physical battery is charged may still be exported and handled under an eligible supplier tariff.
Which option suits a holiday home?+
It depends on empty periods, evening use, security loads, export volume and whether power-cut support matters. A virtual arrangement may suit high export with low local use.
Is simplified surplus compensation the same as a virtual battery?+
No. Simplified compensation values exported energy within the billing framework. A virtual battery is a supplier product that may carry financial credit forward under additional contractual terms.
APPLY IT TO YOUR PROPERTY
Use the guide to ask better questions, then discuss your project.