How we estimate
System size (kW) = monthly use ÷ (peak sun hours × 30 × 0.8 efficiency). Most of the US gets 4 to 6 peak sun hours. Installed residential cost is often $2.50 to $3.50 per watt.
The 30% federal residential clean energy credit ended for systems installed after December 31, 2025. State and utility incentives may still apply.
Example
1,000 kWh a month at $0.17: about a 9.3 kW system costing about $26,900, saving about $1,836 in year one, with payback in about 12.6 years.
Frequently asked questions
Do I need batteries?
No. Grid-tied systems send extra power to the grid, often for bill credits.
See also
Results are estimates for information only and are not financial, legal or medical advice. Rates, taxes and fees vary — confirm with a professional or your lender.