All states / Arizona
Solar in Arizona
At 15.18¢ per kWh and 1755 kWh of production per kW each year, a household paying $200 a month needs a 8.47 kW system. Paid in cash, it returns its $17,715 cost in 12.1 yr.
What we don't know yet
Two prices, two answers
Payback 12.1 yr — at competitive quoted prices ($2.21/W, EnergySage 2026): net cost $17,715, 25-year net $27,237.
Payback 19.7 yr — at typical reported prices ($4.00/W, LBNL 2023): net cost $32,873, 25-year net $12,079.
The gap is methodology, not staleness: the first what you get if you shop around for competitive quotes; the second what the average buyer actually paid, as recorded in permit and incentive data. Every table below uses quoted prices. Why we show both.
By monthly bill
| Your bill | Use / yr | System | Panels | Net cost | Payback | 25-yr net (cash) | Lease, year 1 |
|---|---|---|---|---|---|---|---|
| $100/mo | 6,957 kWh | 3.96 kW | 10 | $7,760 | 13.8 yr | $10,329 | $0 |
| $150/mo | 10,909 kWh | 6.22 kW | 16 | $12,737 | 12.6 yr | $18,781 | $0 |
| $200/mo | 14,862 kWh | 8.47 kW | 22 | $17,715 | 12.1 yr | $27,237 | $0 |
| $300/mo | 22,767 kWh | 12.97 kW | 33 | $27,669 | 11 yr | $44,145 | $0 |
Cash, loan or lease — at $200 a month
| How you pay | 25-year net | Upfront | Year 1 | Payback / cash flow | Federal credit to you |
|---|---|---|---|---|---|
| Cash | $27,237 | $17,715 | $1,429 | 12.1 yr | $0 |
| Loan $137/mo · 6.99% APR · 20 yr | $12,015 | $0 | −$218 | positive from year 19 | $0 |
| Lease / PPA | −$2,647 | $0 | $0 | never | $0 |
The 30% federal credit goes to the system owner, not to you. It is reflected in the rate you are offered. The owner claims it at 30% under IRC 48E.
The inputs, and where they came from
| Input | Value | Source |
|---|---|---|
| Residential electricity rate | 15.18¢/kWh | U.S. EIA API v2, electricity/retail-sales, residential sector, 2026-06 |
| Specific yield | 1755 kWh/kW/yr | NLR (formerly NREL) PVWatts v8 API, 1 kW reference system (city:phoenix-az) |
| Installed cost | $2.21/W | EnergySage Marketplace real-quote average, as of Sep 2026; page updated 2026-08-28 · LBNL Tracking the Sun 2023 median: $4/W, reference only |
| Export compensation | net billing, export credited below retail · 50% | export rate set below retail — not yet verified against the tariff |
| Federal credit, purchase | 0% | IRC 25D (expired) |
| Federal credit, third-party owner | 30% | IRC 48E (Clean Electricity Investment Credit) |
| State incentives | $1,000 | Residential Solar Energy Device Credit (Form 310, A.R.S. 43-1083) (25%, up to $1,000) |
City-level production on file for: Phoenix. The figures above use Phoenix.