Poland Raises the Battery-to-Solar Ratio for Residential Prosumers

Poland is rewriting the rules for home energy storage, with legislation passed by the Sejm set to take effect on December 1, 2026. Under the new framework, a residential battery’s installed power no longer counts against the microinstallation capacity limit — so long as its power rating does not exceed the paired solar array’s output by more than a factor of 2.2.

The change significantly widens what was previously a tight ceiling. Until now, a battery could be excluded from the aggregate limit only if its power matched or fell below the solar plant’s capacity. The law governs electrical power in kilowatts rather than energy volume in kilowatt-hours, which in practice means a 10 kW rooftop system may now be combined with a battery rated as high as 22 kW while still qualifying for simplified prosumer status.

Two requirements apply: the battery-to-solar ratio must stay at or below 2.2, and any electricity fed into the grid must not exceed the system’s total generation capacity — enforced through export-control mechanisms.

To accelerate uptake, Poland’s Ministry of Climate and Environment is committing one billion zlotys to a home-storage subsidy programme, covering up to 30% of installation costs for systems with at least 10 kWh of capacity.

The government forecasts that if 20% of incoming prosumers take advantage of the expanded ratio, aggregate private storage across the country could reach roughly 3.7 GW by the close of 2029. That trajectory appears well-supported by existing demand: battery systems represented 60% of applications in the most recent Mój Prąd programme cycle.

Source: ESS News (pv magazine)