Solar Panel Installation Cost in Seattle, WA

Seattle is served by Seattle City Light (within city limits) or Puget Sound Energy (PSE) in surrounding suburbs. The solar resource here is similar to Portland: about 3.8 to 4.2 peak sun hours per day as an annual average, with the same seasonal swing of great summers and dark winters.

What makes Seattle interesting for solar: • Seattle City Light has some of the lowest electricity rates in the country (about $0.10 to $0.12 per kWh), which hurts the solar payback calculation • PSE rates are higher ($0.11 to $0.14 per kWh) and rising, making suburban Seattle slightly better for solar economics • Washington state has a sales tax exemption for solar installations, saving 8 to 10% on the purchase • Net metering is available through both utilities • The federal 30% ITC expired December 2025 • No state solar rebate program currently active

The honest take: Seattle is not a top solar market. Payback periods are longer than most US cities because of moderate sunshine combined with relatively low electricity rates. But for homeowners motivated by environmental goals who also want to reduce their bills, the numbers are not terrible.

Seattle averages 3.8 to 4.2 peak sun hours per day (annual). Summer production is excellent, with June and July averaging 6+ peak sun hours per day. Winter months (November through February) are rough, with some days producing almost nothing behind solid cloud cover.

A typical 7 kW system in Seattle produces 7,500 to 9,000 kWh per year. That is roughly 15 to 20% less than the same system in Portland and 30 to 40% less than Phoenix or Dallas.

Why it still works for some: • Seattle's cool climate means panels run very efficiently when sunlight is available • The sales tax savings ($2,000+) partially offsets the lower production • If you are on PSE rather than Seattle City Light, rates are higher and approaching levels where the math works better • For homeowners who plan to add an EV, the additional electricity demand improves the solar ROI

Seattle area incentives:

Seattle City Light: • Net metering at retail rate for systems up to 100 kW • Retail rate is low (~$0.10 to $0.12 per kWh), which limits the value of net metering credits • SCL has periodically offered small solar incentive programs but none are currently active for new installs in 2026

Puget Sound Energy (King County suburbs): • Net metering at retail rate • PSE rates are somewhat higher than SCL, improving solar economics • PSE's Green Direct program is not a solar incentive but provides utility-scale renewable energy access

Washington state incentives: • Sales tax exemption for solar energy systems (RCW 82.08.962). This is worth real money given Washington's 10%+ combined sales tax in Seattle. On a $20,000 system you save $2,000+ • No state solar income tax credit (Washington has no state income tax) • Property tax: solar equipment may be exempt from property tax assessment under certain conditions. Check with King County Assessor

Federal: 30% ITC expired December 2025.

Seattle installation notes:

Permitting: Seattle Department of Construction and Inspections handles solar permits. The city has adopted expedited solar permitting for standard residential systems. Processing typically takes 1 to 3 weeks.

Rain and roof condition: Seattle's wet climate demands a solid roof. Moss, lichens, and moisture damage are common on older Seattle homes. Get your roof checked before solar installation. A new roof plus solar is often a smart combined investment.

Electrical service: Many older Seattle homes (Capitol Hill, Ballard, Fremont, Wallingford) have 100A panels that need upgrading for solar. Budget $2,000 to $3,500 for a panel upgrade if necessary.

Installer market: The Seattle area has experienced solar companies. A&R Solar, Puget Sound Solar, Artisan Electric, and others serve the metro area. Get 3 quotes minimum.