Solar by State

Is solar worth it in Seattle in 2026?

A roof in Seattle produces about 1,120 kWh a year per kW of panels. For a home with a $150 monthly bill, a 11.2 kW system costs about $33,482 at Washington's median price and pays for itself in roughly 18.6 years, with no federal tax credit.

Data checked 2026-10-21 · Estimates, not a quote

Solar output in Seattle

1,120kWh per kW a year

Source: PVGIS, NSRDB data

Washington residential electricity price

14.4¢per kWh

Source: EIA, 2026 year to date

Median installed cost in Washington, 2025

$3.00per watt

Source: Berkeley Lab

Calculator · 2026 data, no federal tax credit

How long would solar take to pay for itself?

Simple payback

18.6 years

System size
11.2 kW
Installed cost
$33,482
Savings, year one
$1,800
Net over 25 years
$8,919

Sized to cover your yearly use at today's price. Panels lose 0.5% a year; prices held flat. Method

How Seattle homes get paid for solar

Export rules are set at the state and utility level, not by the city. Seattle is under Washington's full net metering: Washington law (RCW 80.60) credits exports kWh-for-kWh against later use; as of Jan. 2026 neither Puget Sound Energy nor Seattle City Light has adopted a replacement rate. The full rules, incentives and sources are on theWashington page.

Seattle: your utility, incentives and permits

Main utility: Seattle City Light (city-owned). Checked 2026-10-21 against the sources below.

Seattle homes buy their power from Seattle City Light, the city’s own utility, which also serves Shoreline, Lake Forest Park, Burien, Renton, Tukwila, SeaTac, Normandy Park and parts of unincorporated King County.

What City Light gives you for exported power

City Light net meters systems up to 100 kW AC. Every kWh you send to the grid becomes a kWh credit on your bill, and credits you do not use roll over to the next bill. The catch is the yearly reset: under state law, any credits still unused on March 31 go to the utility with no payment to you. Size the system to the power you use in a year, not more. You pay the same customer charges as other homes in your rate class.

Two limits to know:

  • Downtown network. Net metering is not available in City Light’s network areas: most of Downtown and parts of First Hill, South Lake Union and the University District.
  • The state threshold. Washington law makes utilities offer retail-rate net metering until June 30, 2029, or until net-metered systems reach 4% of the utility’s 1996 peak demand, whichever comes first. The WSU Energy Program put City Light at 92.57% of that threshold with data to January 31, 2026. City Light says it has begun planning the next phase of net metering and will give at least six months’ notice before changes take effect.

Incentives in 2026

  • No sales tax on the system. Washington exempts 100% of state and local sales tax on solar systems of 1 kW to 100 kW AC, if installation is completed by December 31, 2029.
  • State production payments are closed. The Renewable Energy System Incentive Program is fully subscribed and is on track to end in winter 2027.
  • Solar for All is paused. The state has paused its no-cost solar program for income-qualified homes until further notice.
  • No federal credit. City Light’s own page notes that projects had to be installed by December 31, 2025; see what ended with the federal credit.

Permits and connection

Every solar electric system needs an electrical permit from the Seattle Department of Construction and Inspections (SDCI), applied for online. Below 12 kW it is an over-the-counter permit: you upload a one-line electrical diagram and the equipment specifications. Above 12 kW it goes to plan review. The 2026 fee for a system below 12 kW is $438, plus a $55.48 administrative fee. A typical single-family rooftop system may not need a building permit if it meets the criteria in SDCI’s Tip 420, which the installer confirms. Owner-occupants may do the electrical work on their own home.

To connect, you file City Light’s online Application for Electric Service and sign its interconnection and net metering agreement. The system cannot be switched on until City Light sends Permission to Operate after the final inspection. The wider Washington rules are on the state page.

Sources

  1. Seattle City Light: about us, service area
  2. Seattle City Light: solar power and net metering
  3. Seattle City Light: solar installation questions, including network areas
  4. Seattle City Light: Level 1 and 2 interconnection and net metering agreement (PDF, revised 2026-08-20)
  5. RCW 80.60.030, net metering credits and the March 31 reset
  6. Washington Department of Commerce: net metering
  7. WSU Energy Program: net metering threshold by utility (data to January 31, 2026)
  8. RCW 82.08.962, sales tax exemption for solar systems
  9. Washington Department of Revenue: solar energy system sales tax exemption
  10. WSU Energy Program: Renewable Energy System Incentive Program
  11. Washington Department of Commerce: Solar for All
  12. Seattle SDCI Tip 420, solar energy systems (updated July 14, 2025)
  13. Seattle SDCI: electrical permit
  14. Seattle SDCI 2026 fee subtitle, table D-15

Why the city matters

Two things change from one city to another in the same state: the sun, which sets how many panels you need, and the utility, which sets what exported power is worth. Seattle gets 1,120 kWh per kW a year on a south-facing roof at a 20° tilt, so covering a year of use for a $150 bill at 14.4¢ takes about 11.2 kW, roughly 28 panels of 400 W. Electricity prices in the calculator are the Washington residential average; your utility's rate can be higher or lower, so put your own bill in.

Other Washington cities: Spokane.

Method: how we calculate payback. Compare all states in theranking or size a system with the panel calculator.