Solar calculators
Panels, yield, and off-grid storage
- SolarOpen calculator
Solar Panel Size
Estimate minimum panel wattage from daily energy use and sun hours.
- SolarOpen calculator
Solar Daily Yield
Estimate daily energy output from panel wattage and sun hours.
- SolarOpen calculator
Solar Battery Bank Size
Size an off-grid battery bank from daily use and backup days.
- SolarOpen calculator
Solar Charge Controller Size Calculator
Estimate minimum charge controller amperage from panel watts and system voltage.
- SolarOpen calculator
Solar Inverter Efficiency Calculator
Calculate inverter efficiency from AC output and DC input power.
- SolarOpen calculator
Solar Array Current Calculator
Estimate array current from total panel watts and system voltage.
- SolarOpen calculator
Solar Panel Tilt Calculator
Recommended panel tilt angle based on your latitude (year-round estimate).
- SolarOpen calculator
Solar Panel Roof Space Calculator
Estimate how many panels fit on your roof and total system size in kW—updates live.
- SolarOpen calculator
Solar Payback Period (ROI) Calculator
Estimate payback time and 25-year savings from system cost, production, and electricity rates.
- SolarOpen calculator
Solar Panel Angle & Tilt Optimizer
Optimal tilt and azimuth from latitude and season—fixed, summer, or winter mounting.
- SolarOpen calculator
Grid-Tie Net Metering Calculator
Compare monthly bills with solar: self-use, export credits, and grid imports.
- SolarOpen calculator
Solar Panel Degradation Calculator
Estimate remaining annual output and capacity after years of panel degradation.