6 kW solar system: what it yields in your municipality
A 6 kWp system is the size most often fitted to Polish family homes today. Pick your municipality and enter the use shown on your bill.
Yearly saving on your bills
PLN 3,482
6,300 kWh produced · 28 % used on site
| Used directly and from the battery | 1,776 kWh |
| Exported to the grid | 4,524 kWh |
| Deposit (×1.23) | PLN 1,540 |
| Deposit spent on energy | PLN 1,482 |
| Overpayment refunded | PLN 58 |
| Bill before / after | PLN 4,592 / PLN 1,168 |
| Pays back in 10 years up to | PLN 34,818 |
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.
A 6 kWp solar system takes about 14 panels of 430–450 W, or 25–30 m² of roof. According to PVGIS it produces about 6,300 kWh a year in Warsaw, and between 5,550 and 6,684 kWh depending on the municipality. With 4,000 kWh of yearly use spread over the whole day, the house uses about 27 % of the output straight away. The rest, about 4,603 kWh, goes to the grid and becomes a prosumer deposit worth PLN 1,569. The total saving on bills is then about PLN 3,425 a year, at 2026 G11 tariff prices and RCEm prices over the last 12 months. The system pays back within 10 years if it costs no more than PLN 34,253 without a grant. The calculator above reworks the same figures for your municipality, use, roof and battery.
Checked by Radif Partners · Editorial policy · Method
Saving from 6 kWp at different levels of use
The same system brings a different benefit to different homes. The higher the use, the more output goes straight to the sockets and the less to the grid at the wholesale price. The table is for Warsaw, a roof at 35° facing south and settlement at RCE.
| Yearly use | Used on site | Saving | With 10 kWh battery | 10-year payback up to |
|---|---|---|---|---|
| 2,500 kWh | 17 % | PLN 2,495 | PLN 2,970 | PLN 24,954 |
| 3,500 kWh | 24 % | PLN 3,264 | PLN 3,880 | PLN 32,637 |
| 4,500 kWh | 30 % | PLN 3,565 | PLN 4,764 | PLN 35,653 |
| 6,000 kWh | 39 % | PLN 3,959 | PLN 5,571 | PLN 39,595 |
The last column is not a market price. It shows how much the system may cost for the saving to repay it within 10 years. If you have an installer’s quote, enter it in the calculator’s “Quoted price” field to see the number of years.
When 6 kWp is too much, and when too little
Too much when the house uses under 3,000 kWh a year: over half the output then goes to the grid, and the deposit has nothing to pay for, since it covers only the energy part of the bill. A surplus above your needs is refunded in cash up to 30% of the value of exported energy at most; the rest is forfeited after 12 months. Such a house is better served by a 4 kW system.
Too little when the house has a heat pump, an electric car or air conditioning running in the daytime. Then compare 8 kW and 10 kW, bearing in mind that a micro-installation’s grid capacity may not exceed the connection capacity of the building.