How this tool sizes your system

You list what you need to run — air conditioner, fridge, water pump, lighting — and how many hours of backup you want at night. The calculator adds the energy up in kilowatt-hours, then proposes a Deye battery that covers it, an inverter that survives your largest surge, and a solar array that puts the energy back in a single day of sun. The array is optional: you can size a battery-and-backup system with no panels at all.

Every figure it shows comes from the specifications printed on the proposed product’s own datasheet, which you can open and read. The result is a sizing estimate, not an electrical design: the final installation is signed off by a licensed installer in your country.