Does solar work during a power cut?

A grid-tied system without a battery switches off when the grid fails. A hybrid inverter with a battery and a separate backup board keeps the selected circuits running.

Can a battery be added to existing solar?

Usually yes, either through a hybrid inverter replacement or an AC-coupled battery inverter. We check the existing inverter and wiring first.

What do you need to give a quote?

Twelve months of bills, the site address for a roof check, and the list of circuits that must stay on during an outage.

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Solar and battery storage in Kosova: sizing and grid connection

7 min readLast reviewed: October 2026

Short answer

A solar and battery system is sized from measured consumption, not from roof area. Start with twelve months of electricity bills or a logged load profile, size the PV array in kWp to cover daytime use, size the battery in usable kWh to cover the evening and the circuits that must stay on during an outage, then pick a hybrid inverter that can carry the largest load that runs at the same time. For commercial sites, 0.8 to 1.5 kWh of usable storage per kWp of PV is a typical starting range. EXBATT designs, installs and commissions these systems in Kosova and Albania and prepares the technical documents for the grid connection.

Most solar quotes start from the roof. We start from the meter. This guide covers the four numbers that decide a solar and battery system, and the order in which a grid-connected installation is approved and commissioned.

1. Measured consumption

Annual kWh tells you how much energy the PV array should produce. The daily profile tells you when it is used. A house that uses most of its energy after sunset needs more battery and less PV than an office that runs from 8:00 to 17:00. Where a load logger is not available, twelve months of bills plus a list of large appliances, heat pumps and motors is the minimum we ask for.

2. PV array in kWp

The array is sized to the energy the site can use or store, not to the largest roof it fits on. Orientation, tilt, shading and the structural capacity of the roof are checked on site before the layout is fixed.

3. Battery in usable kWh

Two questions decide the battery: how much of the evening load should come from stored solar, and which circuits must stay on during an outage and for how long. For a house, 10 to 15 kWh usable usually covers essential loads; carrying a heat pump through an outage needs 20 to 30 kWh with a 10 to 15 kW hybrid inverter. For commercial sites with daily cycling we use lithium iron phosphate (LFP).

4. Hybrid inverter rating

The inverter must carry the largest combination of loads that run at the same time, including the starting current of motors and compressors. If the backup circuits are not separated on their own board, the inverter tries to carry the whole building during an outage and trips.

Grid connection and commissioning

A grid-connected system needs approval from the distribution operator before it exports energy. The rules and limits for self-producers are set by the regulator and change over time, so we check the current conditions for each project. EXBATT prepares the single-line diagram and technical documents for the application, installs the system, and commissions it with written test records handed over to the owner.

Frequently asked

Does solar work during a power cut?: A grid-tied system without a battery switches off when the grid fails. A hybrid inverter with a battery and a separate backup board keeps the selected circuits running.
Can a battery be added to existing solar?: Usually yes, either through a hybrid inverter replacement or an AC-coupled battery inverter. We check the existing inverter and wiring first.
What do you need to give a quote?: Twelve months of bills, the site address for a roof check, and the list of circuits that must stay on during an outage.