Solar panel payback calculator for Poland
A 5 kWp system for PLN 28,000 in a house that uses 4,000 kWh of electricity a year saves about PLN 2,405 a year and pays back in about 11.6 years, or about 10.2 years with the 12% thermal modernisation relief. Enter your use, system size and quoted price to see the payback under net billing and a 25-year balance, with or without a home battery.
Example: 5 kWp, the house uses 4,000 kWh a year
Simple payback: about 11.6 years
saves about PLN 2,405 a yearabout PLN 200 a monthcost after relief and grants about PLN 28,000
- Used straight away: 1,370 kWh, 27%
- Exported: 3,630 kWh, 73%
Power you do not buy: about PLN {avoided}. The deposit for exported energy covers about PLN {deposit} of your bills.
Cumulative balance over 25 years
After 25 years: about PLN 24,393
With degradation and upkeep the balance turns positive for good after about 14.2 years.
Electricity price from 11 October 2026, estimate
| Year | Output | Saving | Costs | Balance |
|---|---|---|---|---|
| Year 1 | 5,000 kWh | 2,405 PLN | 0 PLN | −25,595 PLN |
| Year 5 | 4,901 kWh | 2,375 PLN | 0 PLN | −16,049 PLN |
| Year 10 | 4,779 kWh | 2,338 PLN | 0 PLN | −4,284 PLN |
| Year 12 | 4,732 kWh | 2,323 PLN | 5,500 PLN | −5,130 PLN |
| Year 15 | 4,661 kWh | 2,301 PLN | 0 PLN | 1,795 PLN |
| Year 20 | 4,546 kWh | 2,264 PLN | 0 PLN | 13,187 PLN |
| Year 25 | 4,433 kWh | 2,226 PLN | 0 PLN | 24,393 PLN |
Assumptions and formulaElectricity price from 11 October 2026
output = 5 kWp × 1,000 kWh = 5,000 kWh used on site = 1,370 kWh, exported = 3,630 kWh, bought = 2,630 kWh saving = 1,370 kWh × PLN 1.04 + deposit PLN 980 = PLN 2,405 a year payback = PLN 28,000 ÷ PLN 2,405 = 11.6 years
- Yield per kWp
- 1,000 kWh/kWpPVGIS 5.3 (JRC): Warsaw, south roof at 35°, about 1050 kWh per kWp, 1000 to be safe
- Price per kWp
- 5,600 PLN/kWpKB.pl, solar prices 2026: PLN 5200-6300 gross per kWp
- Electricity price
- 1.04 PLN/kWhURE G11 tariffs 2026 (PGE, Tauron, Enea, Energa), average with distribution
- Value of 1 kWh exported
- 0.27 PLN/kWhPSE RCEm for April-July 2026 weighted by PV output, times 1.23
- Part of the bill the deposit covers (G11 energy)
- 0.62 PLN/kWhG11 energy prices of default suppliers, URE Masz Wybór comparison
- Deposit: multiplier and refund of unused money
- × 1.23, refund up to 30%
- House without heat pump
- 27 %KosztyDomu.pl hourly simulation on PVGIS 2020-2023 data, Warsaw, 1000 kWh/kWp
- Panel degradation
- 0.5 %/yrNREL, Photovoltaic Degradation Rates: median 0.5% a year
- Inverter replacement
- 5,500 PLNSystemy-fotowoltaika.pl: 5 kW inverter replacement with fitting PLN 5000-6000
- Thermal modernisation relief
- No relief
An estimate. Self-consumption comes from a simulation of a typical house near Warsaw, with net billing settled over a year. Fixed charges, changes in the law and battery replacement are not included. Compare at least three offers before you buy.
How electricity, gas, pellet and coal prices have changed, month by month. Price history
Ready-made calculations
How to use the calculator
- Enter your yearly electricity use from the last 12 months of bills. If you plan a heat pump or an electric car, add their use.
- Enter the system size and the price from your quote, per kWp or in total. Below the size you will see the upper limit of a sensible size for your use.
- Choose whether the house has a heat pump. The calculator then estimates self-consumption from our hourly simulation. If you know yours, set it on the slider.
- Check the electricity price and the value of exported energy, pick your thermal modernisation relief rate and add a home battery if you want one.
- Click Calculate payback. The result keeps updating as you change inputs, and you can copy a link to it.
How we calculate the saving and the payback
Every kWh from your panels either stays in the house or goes to the grid. Used straight away, it saves the full price on your bill, on average PLN 1.04/kWh in 2026 G11 tariffs. Exported, it goes into your prosumer deposit: we value it at about PLN 0.27, the April-July 2026 RCEm weighted by solar output and multiplied by 1.23.
Example for 5 kWp and 4,000 kWh of use: the house uses about 1,370 kWh straight away, worth about PLN 1,425, and gets about PLN 980 in the deposit for the 3,630 kWh it exports. That is about PLN 2,405 a year. A PLN 28,000 system pays back in about 11.6 years, in about 10.2 years with the 12% relief and in about 7.9 years with the 32% relief.
The deposit only pays for the energy part of your bill, about PLN 0.62 per kWh bought, not for distribution. When a system is large compared with your use, the calculator applies that limit and the refund of up to 30% of the exported energy value, and shows the rest as money you lose.
Where self-consumption comes from
We simulated hour by hour how much output is used straight away, on PVGIS data for Warsaw from 2020-2023, for a house that uses 30% of its electricity between 9:00 and 17:00. With 4,000 kWh of use, a 3 kWp system reaches 40% self-consumption and pays back in about 9.7 years, 5 kWp reaches 27%, and 8 kWp only 19%, with payback in about 13.5 years.
That is why the calculator suggests an upper size limit: yearly use divided by the yield per kWp. Every kWh you move from exporting to using yourself is worth about PLN 0.77. If you run the washing machine, dishwasher and water heating in daytime or have a battery, set your own self-consumption on the slider.
The 25-year balance and what the calculator leaves out
Simple payback divides the cost by the first-year saving. The 25-year balance adds panel degradation of 0.5% a year (the NREL median from field measurements) and an inverter replacement in year 12 for PLN 5,500. In the 5 kWp example the balance turns positive for good after about 14.2 years and reaches about PLN 24,393 after 25 years at 2026 electricity prices.
The calculator does not include fixed charges on your bill, changes in the law after 2026 or replacing a home battery, whose warranty usually lasts 10 years. It does not know how shaded your roof is either. Use the result to compare options under stated assumptions, and get at least three quotes before you buy.
Frequently asked questions
How long does a 5 kWp solar system take to pay back in Poland?
In a house that uses 4,000 kWh a year, a 5 kWp system for PLN 28,000 saves about PLN 2,405 a year and pays back in about 11.6 years. With the 12% thermal modernisation relief it takes about 10.2 years, with the 32% relief about 7.9 years.
What system size should I choose for 4,000 kWh of use?
At most about 4 kWp, which is yearly use divided by about 1,000 kWh per kWp. In our simulation 3 kWp pays back in about 9.7 years, 4 kWp in about 10.8 years and 5 kWp in about 11.6 years. A larger system saves more money a year, but each extra kWp pays back more slowly.
Is a home battery worth it with solar panels?
It saves more a year but pays back more slowly. A 5 kWp system with a 10 kWh battery for PLN 25,000 saves about PLN 3,574 instead of about PLN 2,405 a year. With the Home Energy Storage grant and the 12% relief the set pays back in about 11.2 years, the panels alone in about 10.2 years. Without any support: about 14.8 years against about 11.6 years.
What is 1 kWh exported to the grid worth under net billing?
The calculator uses about PLN 0.27: the April-July 2026 RCEm weighted by solar output, times 1.23. The money goes into your deposit and only covers the energy part of your bill, about PLN 0.62 per kWh bought. If you know your own settlement, enter a different value.
Does the calculator include grants?
We found no national grant for panels alone in 2026, so the other grant field defaults to PLN 0. For a battery the calculator adds the Home Energy Storage programme: 30% of the cost, at most PLN 800 per kWh and PLN 16,000, if the battery has at least 10 kWh and twice the system size. Applications open on 20 October 2026.