State solar profile · #50 of 51
Solar in Washington: cost, payback & incentives
What a typical home should expect from solar in Washington - sunshine, electricity rates, modeled payback, and the 3 incentive programs that change the math, built from NREL, EIA, and DSIRE data.
- 3.5
- kWh/m²/day irradiance
- 10.5¢
- avg electricity rate
- 26.6 yr
- payback (#51)
- 3
- incentive programs
The verdict
Washington scores 14/100 for solar - #50 of 51 - with a modeled 26.6-year payback and roughly a $1,000 shortfall over 25 years on a typical 6 kW system before any incentives.
- 14/100
- solar score (#50)
- 26.6 yr
- modeled payback (#51)
- $644
- modeled annual savings
- full
- net-metering policy
All figures are modeled from public NREL/EIA/DSIRE data for a typical 6 kW system; your result depends on roof, shading, utility tariff, and installer pricing.
Washington at a glance
3.5
irradiance (kWh/m²/day)
10.5¢
electricity rate (per kWh)
$17,100
6 kW system cost
26.6 yr
est. payback (#51)
6,132
kWh/year (6 kW)
$644
annual savings
25-year ROI for a 6 kW system
$17,100
system cost
$644/yr
modeled savings
26.6 yr
break-even
-$1,000
25-year net
Estimates from state averages; actual results vary by system size, roof orientation, shading, utility rate, and installer pricing. Run a personalized estimate →
Installed solar capacity in Washington, 2007–2024
Total solar nameplate capacity in Washington reported to the EIA, utility-scale and reported distributed systems.
Where Washington sits nationally
Every state by sunshine (left-to-right) and payback speed (faster toward the bottom). Washington is highlighted, its position shows whether sun or electricity rates drive its return.
Washington (highlighted): 3.5 kWh/m²/day, 26.6-yr modeled payback - slower than the national average.
What the data says about solar in Washington
Washington ranks #50 of 51 with a composite solar score of 14/100 (Marginal). The score blends inputs from NREL and EIA: average irradiance of 3.5 kWh/m²/day, residential electricity at 10.5¢/kWh, a turnkey 6 kW installed cost of $17,100 ($2.85/W), and 3 tracked state and utility incentive programs.
On those inputs, a 6 kW array here is modeled to generate roughly 6,132 kWh/year and offset about $644 in annual utility spending at the state's average rate, an estimated 26.6-year simple payback (#51 of 51 for speed to break-even) and a projected -$1,000 net position over a 25-year horizon before utility-rate escalation.
Policy matters as much as physics. Washington's net-metering framework is classified as full, which governs how exported generation is credited, and its renewable portfolio standard is: Mandatory (100% by 2045). The 3 active programs tracked in DSIRE include tax exemption and net metering types, each can stack to compress payback. Notable programs include Bonneville Power Admin Incentive, PSE Solar. Note that the 30% federal residential solar tax credit (§25D) ended for systems placed in service after December 31, 2025, so state and utility incentives now carry more of the economics, confirm current federal rules with the IRS and your tax advisor.
Solar & grid details
- Net-metering policy
- full
- Renewable portfolio standard
- Mandatory (100% by 2045)
- Installed cost / watt
- $2.85/W
- Annual production (6 kW)
- 6,132 kWh
- Installed capacity (EIA 2024)
- 268 MW
- Notable programs
- Bonneville Power Admin Incentive, PSE Solar
Top incentive programs
3 programs available for Washington residents
All Washington solar incentives (3)
WA Solar Property Tax Exemption
Property tax exemption
Washington provides a property tax exemption for qualifying solar energy systems.
Tax exemptionWA Solar Sales Tax Exemption
Sales tax exemption
Washington exempts solar energy systems from retail sales and use taxes.
Net meteringWA Net Metering
Retail rate credit
Washington utilities offer net metering for systems up to 100 kW.
Your next step
How to act on Washington's numbers.
- Run the savings calculator with your real electricity bill, the figures above use state averages, not your usage. Calculate for Washington
- Check net-metering and SREC value before signing, in a "full" state, export compensation often decides the return. Net-metering guide
- Stack Washington's 3 incentive programs, each lowers net cost or raises annual return. See all programs
Modeled estimates from public data, not financial advice; a binding figure requires a site-specific assessment from a licensed installer.
Solar resource from NREL; electricity rates and installed capacity from the U.S. EIA; incentive programs from DSIRE. See our methodology.