How it works
Fill in the 3 fields above and Solar Panel System Size Calculator calculates the result instantly, recalculating as you change any value. The math runs locally in your browser — nothing is sent to a server.
Examples
- Monthly usage 900 kWh, Peak sun hours 4.5 h/day, Panel wattage 400 W → System size: 8.33 kW
Frequently asked questions
How do I use the Solar Panel System Size Calculator?
Enter your values in the 3 input fields and the result is calculated automatically as you type. Change any value to see the numbers update instantly.
Is my data private?
Yes. The Solar Panel System Size Calculator runs entirely in your browser. Nothing you enter is uploaded, saved to a server, or shared — it never leaves your device.
Is the Solar Panel System Size Calculator free?
Yes, it is completely free with no sign-up, no limits and no watermarks. Like every tool on environment and the rest of the platform, you can use it as often as you like.
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