Is solar worth it in Washington?
A 7.0 kW rooftop system near Seattle produces about 7,615 kWh a year. Priced against the 38 residential tariffs currently on file in Washington, payback runs from 13 years on the best of them to 77 on the worst.
Why the tariff matters more than the panels
Two households in Washington with identical roofs and identical systems can see paybacks 13 and 77 years apart, purely because they are on different tariffs. Solar produces at midday; households consume in the evening. Only 63% of what these panels make is used as it is made — the rest is exported, and what an exported kWh earns is set by the tariff and by state net metering rules, not by the hardware.
That is why the figures here are computed hour by hour against each real tariff rather than by taking a bill and assuming solar removes a share of it. How this is modeled →
Payback by tariff in Washington
7.0 kW system at $3.00/W, household using 1000 kWh a month, no incentives. A range means the export credit is not filed with the tariff and the outcome depends on net metering rules — 38 of 38 tariffs here belong to a utility that reports residential net metering.
| Utility | Tariff | Structure | Annual saving | Payback |
|---|---|---|---|---|
| Puget Sound Energy Inc | 327 (Residential Time of Use 3-tier Pilot) - Three Phase | Time-of-use | $895–$1,617 | 13–23y |
| Puget Sound Energy Inc | 7 (Residential Service - Single Phase) | Tiered | $1,003–$1,554 | 14–21y |
| Puget Sound Energy Inc | 7 (Residential Service - Three Phase) | Tiered | $1,003–$1,554 | 14–21y |
| Puget Sound Energy Inc | 307 (Residential Time of Use Pilot) - Single Phase | Time-of-use | $699–$1,479 | 14–30y |
| Puget Sound Energy Inc | 307 (Residential Time of Use Pilot) - Three Phase | Time-of-use | $699–$1,479 | 14–30y |
| Puget Sound Energy Inc | 327 (Residential Time of Use 3-tier Pilot) - Single Phase | Time-of-use | $719–$1,441 | 15–29y |
| Puget Sound Energy Inc | 8 (Residential & Farm General Service - Three Phase) | Time-of-use | $898–$1,433 | 15–23y |
| Puget Sound Energy Inc | 8 (Residential & Farm General Service - Single Phase) | Time-of-use | $898–$1,433 | 15–23y |
| Puget Sound Energy Inc | 317 (Residential Time of Use with Peak Time Rebate Pilot) - Three Phase CLOSED RATE | Time-of-use | $690–$1,207 | 17–30y |
| City of Seattle, Washington (Utility Company) | Schedule RSL-Residential: Lake Forest Park | Flat | $728–$1,160 | 18–29y |
| City of Seattle, Washington (Utility Company) | Schedule RSE-Residential: SeaTac | Flat | $728–$1,160 | 18–29y |
| City of Seattle, Washington (Utility Company) | Schedule RSB-Residential: Burien | Flat | $728–$1,160 | 18–29y |
| City of Seattle, Washington (Utility Company) | Schedule RSH-Residential: Shoreline | Flat | $728–$1,160 | 18–29y |
| City of Seattle, Washington (Utility Company) | Schedule RSB-Residential: King County | Flat | $728–$1,160 | 18–29y |
| City of Seattle, Washington (Utility Company) | Schedule RST-Residential: Tukwila | Flat | $723–$1,151 | 18–29y |
Price it for your own usage and system size →
What would change this
Your roof. Production is modeled for Seattle on a south-facing array at 20° tilt. Shading, orientation and pitch all move it, and solar resource varies within Washington itself.
Your usage pattern. A household at home during the day self-consumes more and exports less, which shortens payback wherever export credit is poor.
Rising rates. These figures hold today's prices flat. Electricity prices have been rising, and every rise shortens payback — so treat these as a conservative bound.
State and local incentives. Not included here, and in some states they are worth more than the federal credit was. Check your state energy office before deciding.