Last updated: June 1, 2026

Solar Panel Calculator

Estimate the solar panel system size needed to offset your electric bill, plus installation cost and payback period.

Monthly Electric Bill ($)

Electricity Rate ($/kWh)

Peak Sun Hours/Day

US average: 4-6 hours

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It depends on your electricity usage and sun exposure. A typical home needs 15-25 panels (400W each).

Most residential solar systems pay for themselves in 6-12 years through electricity savings.