Solar Panel Calculator

Calculate solar panel needs: daily kWh usage, sun hours, panel wattage, system losses. ROI estimate.

Monthly Electric Bill ($)

Electricity Rate ($/kWh)

-- OR -- Daily kWh Usage

Offset Target (%)

Peak Sun Hours/Day

Panel Wattage (W)

System Losses (%)

Cost per Watt (installed)

Tax Credit (%)

Annual Rate Increase (%)

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