Solar panel payback calculator: when does it pay off?
This solar panel payback calculator shows whether a solar system is worth it for you: enter system size, installed cost, yearly yield, self-consumption and your electricity and export prices. You get the payback year, the profit after the period and the cost per kWh you generate.
Source: Wikipedia – Photovoltaic system. Updated: .
How it is calculated
A solar system pays for itself once its benefit from saved grid power and export income exceeds its cost. The calculator shows that point and the profit after it.
How it is calculated
- Yield: system size × yearly yield per kW, reduced each year by the output loss.
- Benefit: self-consumption × electricity price plus the rest × export price; the electricity price rises by the percentage you set.
- Cost: installed cost minus incentive plus the running costs for each year.
- Cost of generation: total cost divided by total yield – the price at which you produce a kWh yourself.
What drives the result
- Self-consumption: power you use yourself saves the full grid price, exported power only earns the export rate. A battery or shifted usage raises the share.
- Location and direction: they set the yearly yield.
- Installed cost per kW: larger systems are usually cheaper per kW.
All values are your assumptions, not a forecast; export rates, prices and incentives change. Use the figures from your quote and your electricity bill. Your entries stay in your browser.
Frequently asked questions
How long does it take for solar panels to pay for themselves?
Until the savings plus export income add up to more than the system cost. The higher your self-consumption and electricity price, the sooner; the calculator shows the year.
What is the yearly yield per kW?
It depends on location, roof pitch and direction. Typical values run from about 900 to 1,500 kWh per kW per year. Your installer can give you a figure for your roof.
Why does self-consumption matter?
Each kWh you use yourself replaces grid power at the full price, while exported power earns only the export rate. A battery raises the share but costs extra.
Which export price should I enter?
The rate that applies to your system. It comes from your utility or program, is adjusted from time to time and differs between regions.
What is the cost of generation?
The total cost of the system divided by all kWh it produces. If it is below your grid price, self-generated power is cheaper.
Are my entries private?
Yes. Everything is calculated in your browser; nothing is uploaded.
Sources and legal basis
As of: · Editorial policy
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