Solar Installation Cost
The total installed cost of a residential solar system, typically $2.50–$4.00 per watt before incentives — highly variable by system size, location, and installer.
Residential solar system costs have fallen 90% since 2010. In 2024, the U.S. average installed cost is approximately $2.80–$3.20 per watt before incentives, yielding $25,000–$32,000 for a typical 9–10 kW system. After the 30% federal tax credit, net costs are $17,500–$22,400.
Cost components: panels (25–30% of total), inverters (10–15%), mounting/racking (10–15%), electrical work and wiring (10%), labor (20–30%), permitting and inspection (5–10%), and installer overhead/profit (10–20%). Premium brands (SunPower, REC) cost more per watt but may reduce long-term replacement costs.
Geographic variation is substantial: California, Hawaii, and Massachusetts installations typically cost $0.50–$1.00/watt more due to higher labor costs and complex permitting. Installer competition also drives prices: getting 3–5 quotes from independent installers (not just national brands) routinely saves $3,000–$8,000. System size has a strong economy of scale — the cost per watt for a 5 kW system is typically $0.50–$0.75/watt higher than a 12 kW system.
Real-World Example
Three quotes for an identical 10 kW system with Enphase microinverters ranged from $28,500 to $41,000 — the highest bidder was a national brand using direct sales staff; the mid-range $32,000 quote from a local 50-employee installer won after reference checks confirmed quality.