Balcony solar: how much power it gives and what to notify
Two panels on a balcony rail are a small system, but still a micro-installation in law. Work out what yours would give.
Yearly saving on your bills
PLN 834
840 kWh produced · 87 % used on site
| Used directly and from the battery | 730 kWh |
| Exported to the grid | 110 kWh |
| Deposit (×1.23) | PLN 35 |
| Deposit spent on energy | PLN 35 |
| Overpayment refunded | PLN 0 |
| Bill before / after | PLN 2,733 / PLN 1,900 |
| Pays back in 10 years up to | PLN 8,338 |
Hourly model of an average day in each month; surplus priced at the last 12 months of RCEm (PSE) plus the gain from negative RCE counted as zero. An estimate, not an offer; fixed charges excluded.
Balcony solar usually means two panels of about 0.8 kWp in total, fixed vertically to the balcony rail or on a frame, with a micro-inverter connected to the flat’s wiring. According to PVGIS, two 400 W panels hung vertically on a south-facing balcony give about 604 kWh a year on average in Poland, and the same panels on a 35° frame about 848 kWh. A vertical panel loses out in summer, but in winter, with the sun low, it gives more than a tilted one. In a flat using 2,500 kWh a year you use most of this output straight away on the fridge, router and devices on standby, which at 2026 G11 prices saves about PLN 659 a year. Polish Energy Law has no separate procedure for balcony systems: every micro-installation connected to the grid is notified to the distribution system operator, which has 30 days to connect it and fits a two-way meter at its own cost.
Checked by Radif Partners · Editorial policy · Method
What 0.8 kWp gives on a balcony: four ways to mount it
The table compares two 400 W panels in a flat using 2,500 kWh a year. Output is the average municipal PVGIS 5.3 yield adjusted by factors for each angle and direction, computed in PVGIS for Warsaw. The saving covers self-consumption at the 2026 G11 price and the deposit from energy exported at RCE.
| Mounting | Per year | In December | Used at once | Yearly saving |
|---|---|---|---|---|
| vertical, south | 604 kWh | 22.9 kWh | 100 % | PLN 659 |
| vertical, south-east | 571 kWh | 17.4 kWh | 100 % | PLN 624 |
| vertical, east | 427 kWh | 6.6 kWh | 100 % | PLN 466 |
| 35° frame, south | 848 kWh | 19.8 kWh | 87 % | PLN 839 |
A frame gives more over the year, but a vertical panel gives more in December. With two panels almost all the output stays in the flat, so the saving grows with output and little goes to the grid. Every type of mounting needs a firm fixing to the rail, designed for wind load.
How much power will a balcony panel give?
Yearly output
604 kWh
| System size | 0.80 kWp |
| Used at once at home (2,500 kWh/yr) | 100 % |
| Yearly saving, once notified to the DSO | PLN 659 |
Average municipal yield from PVGIS 5.3, 90° factors from PVGIS (Warsaw), G11 2026, RCE.
Notifying a micro-installation step by step
A balcony system plugged into a socket or wired into the flat’s circuit is a micro-installation if it feeds power to the grid through the flat’s wiring. The notification under Art. 7(8d4) of the Energy Law is filed with the distribution system operator in your region. It contains your details, the type and power of the system, information on meeting the technical requirements and the location, plus a declaration of legal title to the property. The operator confirms the date of notification and has 30 days to connect, and bears the cost of the meter and protection itself.
Once connected you are settled like any prosumer: energy used at once is free, and the surplus goes into the deposit under net-billing. You can check the power entered in the notification in the calculator at the top of the page, and the exact output for your balcony, with a 90° angle and shade, in the PVGIS tool listed in the sources.