Kalkulix

Solar Panel ROI Calculator – Poland 2026

Enter your solar system's parameters or use the simple wizard to find out the annual savings, payback period and electricity production in Poland.

Basic

Setup 1
Payback period6.94 years
Annual savingsPLN 3,858.75
Lifetime savingsPLN 117,457.12
Annual production6860 kWh
CO₂ saved3.79 t/year
Self-consumption35 %

This calculation is indicative and is based on the entered inputs and average values for Poland (specific yield, electricity prices, a simplified average feed-in price rather than an exact net-billing model). Actual production and savings depend on the specific roof, orientation, shading and installer. It does not replace a quote from a solar installer.

How solar panel ROI is calculated

Annual production is calculated as the installed capacity (kWp) multiplied by the specific yield (kWh produced per year per 1 kWp) for the given location in Poland. Part of the electricity produced is used directly by the household (self-consumption), while the rest is exported to the grid at the feed-in price.

Annual savings are the sum of two parts: money saved on electricity that would otherwise have been bought (self-consumption × electricity price), and income from surplus exported to the grid (remaining production × feed-in price). Poland has used a net-billing system with an hourly market price since 2022; the calculator uses a simplified average feed-in price instead.

The payback period is the year in which cumulative savings exceed the net investment (system and any battery price, minus the Mój Prąd subsidy). The calculator also accounts for the annual rise in electricity prices and the gradual degradation of panel output.

The calculator lets you compare 2–3 setups side by side, for example a system without a battery and one with a battery, and immediately see the difference in payback period and total savings.

Frequently asked questions

How is the annual solar production calculated?

Multiply the system size in kWp by the location's specific yield in kWh/kWp/year. In Poland, the typical figure is around 950–1050 kWh/kWp/year, slightly higher in the south.

What does self-consumption mean and why does it matter?

It's the share of produced electricity you use directly instead of exporting it to the grid. Higher self-consumption means a faster payback, because purchased electricity is more expensive than the feed-in price for surplus.

Is battery storage worth it?

A battery increases self-consumption and therefore savings, but also increases the investment. Compare the setup with and without a battery in the calculator – the higher the electricity price and daytime usage, the sooner a battery pays off.

How does the Mój Prąd subsidy affect the payback period?

It reduces the net investment by the subsidy amount, shortening the payback period. It doesn't affect the annual savings. Check the current conditions on the website of the Polish National Fund for Environmental Protection (NFOŚiGW).

Why does production decrease over time?

Solar panels gradually lose a small amount of output over time (degradation, typically around 0.5% per year). The calculator accounts for this in the production and savings estimate over the system's full lifetime.

How much CO₂ does a home solar system save?

It depends on annual production and the emissions factor of the Polish electricity grid, which is significantly higher than in Czechia or Slovakia due to the large share of coal generation. The calculator converts the electricity produced into tonnes of CO₂ saved per year based on the current energy mix.

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