What a 15 kW solar system costs
About 38 panels, roughly 836 square feet of roof, and $56,250 at the national median of $3.75 a watt. There is no federal credit to subtract from that any more.
The numbers
The same system bought before 31 December 2025 would have cost $39,375 after the 30% federal credit. That credit no longer exists, so this system is $16,875 more expensive than an identical one installed a year earlier. What changed.
A 15 kW system in the states we have local prices for
| State | Per watt | Price | Makes | Saves, year one | Payback |
|---|---|---|---|---|---|
| Massachusetts | $3.74 | $56,100 | 18,945 kWh | $5,776 | 9.0 years |
| New York | $3.98 | $59,700 | 18,825 kWh | $5,629 | 9.7 years |
| Rhode Island | $3.75 | $56,250 | 18,870 kWh | $5,338 | 9.7 years |
| California | $4.36 | $65,400 | 24,030 kWh | $5,654 | 10.5 years |
| Connecticut | $3.75 | $56,250 | 19,170 kWh | $4,631 | 11.0 years |
| Delaware | $3.18 | $47,700 | 19,125 kWh | $3,534 | 12.1 years |
| Arizona | $3.62 | $54,300 | 25,320 kWh | $3,894 | 12.4 years |
| Wisconsin | $3.73 | $55,950 | 18,840 kWh | $3,591 | 13.7 years |
| Texas | $3.46 | $51,900 | 20,835 kWh | $3,309 | 13.8 years |
| Florida | $4.08 | $61,200 | 21,390 kWh | $3,215 | 16.3 years |
| Oregon | $3.90 | $58,500 | 16,170 kWh | $2,582 | 18.9 years |
Three competing quotes beat any amount of comparing panel brands
Sales cost and margin are over a third of an installed price, and they are the part that competition removes. A single quote from whoever reached you first is how people end up in the top quarter of what their neighbours paid.
Plain outbound links. We take no phone numbers and sell no leads: you give your details to the company that will actually call you, not to us.
Prices and rules change. We will tell you when they do
Berkeley Lab publishes installed prices once a year, the EIA updates electricity rates every month, and Congress changed the tax treatment of all of this in 2025. One email when something on this site actually changes, and nothing else.
Email address only. No phone field, no passing you to installers, unsubscribe in one click.