Washington's Solar Split Personality: Wet West vs. Dry East
Washington State presents a solar paradox: it's home to both Seattle (the rainiest major city in America) and Spokane (which receives 2,300+ sunshine hours per year). As of 2026, Washington ranks 24th in the United States for total installed solar capacity, according to the Solar Energy Industries Association (SEIA).
The state has over 1,200 MW of installed solar capacity, enough to power more than 140,000 homes. However, solar adoption is highly regional:
- Western Washington (Seattle, Tacoma, Olympia): Limited sunshine (1,600–1,800 kWh/kW/year), but excellent summer production (long days, cool temperatures that improve panel efficiency).
- Eastern Washington (Spokane, Tri-Cities, Yakima): Abundant sunshine (1,900–2,100 kWh/kW/year), similar to Colorado or northern California.
Despite the reputation, Seattle actually receives more sunshine hours than Germany (2,100+ hours/year vs. 1,800 hours/year), and Germany is a world leader in solar adoption. The key is that Western Washington's production is highly seasonal: 70% of annual production occurs between April and September.
Understanding Washington's Electricity Rates in 2026
Washington's electricity rates are below the national average. As of 2026, the statewide average is approximately $0.10/kWh, according to the U.S. Energy Information Administration (EIA). This is primarily due to the state's abundant hydropower resources (hydroelectricity provides ~60% of Washington's electricity).
1. Seattle City Light (Seattle & Surrounding Areas)
Seattle City Light is a municipal utility that serves approximately 1.1 million residents in Seattle and surrounding areas. Their 2026 residential rate is approximately $0.09/kWh (including basic charge, energy charge, and taxes). A typical household using 900 kWh per month pays about $81 per month.
Seattle City Light also offers net metering for solar customers (up to 100 kW systems), crediting excess solar at the full retail rate.
2. Puget Sound Energy (Western WA)
Puget Sound Energy (PSE) serves approximately 1.2 million customers in western Washington (Tacoma, Bellevue, Everett). Their 2026 residential rate is approximately $0.11/kWh, slightly higher than Seattle City Light due to different generation costs (PSE uses more natural gas).
A typical household in the PSE territory using 900 kWh per month pays about $99 per month.
3. Avista Utilities (Eastern WA – Spokane)
Avista serves approximately 160,000 customers in eastern Washington (Spokane, Spokane Valley). Their 2026 residential rate is approximately $0.10/kWh. A typical household using 900 kWh per month pays about $90 per month.
4. Pacific Power (Southern WA)
Pacific Power serves approximately 120,000 customers in southern Washington (Vancouver, Longview). Their 2026 residential rate is approximately $0.10/kWh, similar to other Washington utilities.
Washington Net Metering Policy in 2026
Washington does not have a state-wide net metering law. However, many utilities offer net metering voluntarily as a customer service. This means policies vary by utility:
| Utility | Net Metering? | Export Credit Rate |
|---|---|---|
| Seattle City Light | ✅ Yes | Full retail (~$0.09/kWh) |
| Puget Sound Energy | ✅ Yes (voluntary) | Full retail (~$0.11/kWh) |
| Avista Utilities | ✅ Yes (voluntary) | Full retail (~$0.10/kWh) |
| Pacific Power | ✅ Yes (voluntary) | Full retail (~$0.10/kWh) |
Important: If your utility does not offer net metering, you can still install solar, but you'll need battery storage to maximize self-consumption. Check with your specific utility before installing.
Washington Solar Incentives in 2026
Washington offers limited state-level incentives compared to leading solar states. However, you can still benefit from:
1. Federal Tax Credit (30%)
The 30% federal Investment Tax Credit (ITC) applies to Washington solar installations, reducing the cost of a typical 7 kW system from $18,760 to $13,132.
2. Sales Tax Exemption
Solar energy equipment purchased for use in Washington is exempt from state sales tax (currently 6.5%, plus local sales taxes that can bring the total to 8.5–10.4% in some areas). This saves approximately $1,200–$1,900 on a typical 7 kW system.
Note: To qualify for the sales tax exemption, your solar installer must be certified by the Washington State Department of Revenue. Most reputable installers are certified — ask before signing a contract.
3. Property Tax Exemption (Partial)
Washington law (RCW 84.36.070) provides a partial property tax exemption for solar energy systems. The exemption applies to the increased value of the property due to solar, but only up to $5,000 of assessed value. This is a relatively modest benefit compared to other states.
4. Seattle City Light Solar Incentive (Legacy)
Seattle City Light previously offered a solar production incentive ($0.16/kWh for the first 3,000 kWh/year). This program ended in 2024 for new participants. Existing participants continue to receive payments until 2029.
Real-World Case Study: Tom's 7 kW System in Seattle, WA
To illustrate what a typical Western Washington solar installation looks like, here's a case study based on a real homeowner (name changed for privacy):
Tom's situation (Seattle, WA – Seattle City Light territory):
- Home: 1,900 sq ft single-family home built in 2005
- Monthly electricity bill: $88 (980 kWh per month)
- Roof: South-facing, 5/12 pitch, no shading from trees
- System installed (May 2026): 7 kW (20 × 350W panels)
- Total cost: $18,760 ($2.68/watt)
- After federal tax credit (30%): $13,132
First 4 months of production (May–August 2026):
| Month | Solar Production (kWh) | Electricity Usage (kWh) | Net Grid Draw (kWh) | Bill After Solar |
|---|---|---|---|---|
| May 2026 | 850 | 920 | 70 | $6.30 |
| June 2026 | 980 | 1,050 | 70 | $6.30 |
| July 2026 | 1,050 | 1,120 | 70 | $6.30 |
| August 2026 | 1,020 | 1,080 | 60 | $5.40 |
Tom's savings in the first 4 months:
- Without solar: $88 × 4 = $352
- With solar: $6.30 + $6.30 + $6.30 + $5.40 = $24.30
- Net savings: $327.70 in 4 months ($983/year projected)
- Payback period: 13.4 years ($13,132 net cost ÷ $983 annual savings)
Tom's advice for Washington homeowners: "Don't let Seattle's rainy reputation scare you away from solar. My system produces 80% of its annual output between April and September. Winter production is low, but net metering credits from summer offset winter bills. It's a longer payback than in California, but the 30% federal tax credit makes it worthwhile."
Factors That Affect Your Solar Savings in Washington
1. Western vs. Eastern Washington
Your location within Washington dramatically affects solar production:
- Seattle: ~1,600 kWh/kW/year (similar to Germany)
- Spokane: ~1,900 kWh/kW/year (similar to Colorado)
- Difference: A 7 kW system in Spokane produces 2,100 more kWh/year than the same system in Seattle, worth approximately $210/year in additional savings.
2. Roof Orientation & Shade
Western Washington's latitude (47–48°N) means that south-facing panels with a 35–45° tilt angle capture the maximum annual sunlight. However, because production is so seasonal, even east- or west-facing panels can be viable if you have high summer air conditioning loads.
Shade from trees is a bigger problem in Western Washington than in sunny states, because winter production is already low. Losing 20% of production to shade can cost you $150–$200 per year in lost savings.
3. Net Metering Variability
Because Washington does not have a state-wide net metering law, your utility's policy is critical. Before installing, confirm in writing that your utility offers net metering and will continue to do so for the next 25 years.
Washington Solar Installers: What to Look For
Washington has a growing solar installation market, with over 200 licensed solar contractors operating in the state (Washington State Department of Labor & Industries, 2026). Key factors to consider:
- Washington contractor license – Ensure your installer has a valid Washington contractor license and is certified for solar PV installation.
- Experience with your utility – An installer familiar with Seattle City Light's or PSE's interconnection process can save you weeks of delays.
- Rainy weather installation capability – Western Washington has frequent rain. Choose an installer who can work safely in wet conditions and properly seal roof penetrations to prevent leaks.
Environmental Impact: Washington's Clean Energy Transition
Beyond financial savings, installing solar in Washington contributes to the state's transition away from coal (which still provides ~10% of Washington's electricity). As of 2026:
- Washington's solar installations have displaced approximately 400,000 metric tons of CO₂ emissions per year, equivalent to taking 87,000 cars off the road (NREL, 2026).
- The solar industry employs over 2,800 Washingtonians, from installation to operations and maintenance (SEIA, 2026).
- Washington has committed to 100% clean electricity by 2045. Residential solar is a key part of that strategy. By installing solar, you're helping Washington meet its climate goals.
Data Sources & Methodology
This Washington solar calculator and article are based on the following authoritative sources:
- U.S. Energy Information Administration (EIA) – Washington electricity rates (2026)
- Solar Energy Industries Association (SEIA) – Washington solar market data (2026)
- Database of State Incentives for Renewables & Efficiency (DSIRE) – Washington net metering policy and tax exemptions
- National Renewable Energy Laboratory (NREL) – PVWatts solar production estimates for Washington locations
- Seattle City Light – Net metering policy and rates (2026)
- Washington State Department of Revenue – Sales tax exemption for solar
Calculator Methodology: Our savings estimates use the 25-year cash flow model with the following assumptions: 3.5% annual electricity inflation, 0.5% annual panel degradation, $500/year maintenance costs (inverter replacement in year 15), and Seattle City Light's net metering policy. Your actual savings may vary depending on your specific utility rates, roof characteristics, and equipment choices.
Frequently Asked Questions About Solar in Washington
Probably not for financial reasons. Western Washington has reliable grid infrastructure (thanks to hydropower), and most utilities offer net metering. However, battery storage can provide peace of mind during rare winter storms (such as the 2021 windstorm that caused multi-day outages). If you value backup power, a small battery (such as the Enphase IQ 10) may be worthwhile despite the longer payback period.
Yes, significantly. Spokane receives 2,300+ sunshine hours per year, compared to Seattle's 2,100 hours. More importantly, Eastern Washington has clearer winter skies (less cloud cover), which means winter production is 30–50% higher than in Western Washington. If you live in Eastern Washington, your payback period will be 2–4 years shorter than an equivalent system in Seattle.
Washington's sales tax exemption (RCW 82.08.027) applies to the total cost of the solar system (equipment + installation labor). To qualify, your installer must provide a certificate of exemption at the time of sale. The exemption applies to both state sales tax (6.5%) and local sales tax (which varies by location, typically 2–3.9%). In Seattle, the total sales tax rate is 10.4%, so the exemption saves approximately $1,950 on a typical 7 kW system.
Studies show that homes with solar panels sell for 4–6% more than comparable homes without solar (Lawrence Berkeley National Laboratory, 2026). In Washington's competitive housing market (particularly in Seattle, Bellevue, and Tacoma), solar can be a significant selling point. If you still owe money on a solar loan, you'll typically need to pay off the loan at closing or transfer it to the buyer (with lender approval). Leased systems are more complicated and may require buying out the lease or finding a buyer willing to assume the lease.
Explore Solar Calculators for Other States
Every state has different electricity rates, incentives, and net metering policies. Compare your Washington savings with neighboring states:
- Oregon Solar Calculator – Oregon has similar rainfall but different incentives
- Idaho Solar Calculator – Idaho has cheaper electricity
- Montana Solar Calculator – Montana has excellent solar resources
- British Columbia Solar Calculator – For our Canadian neighbors
Or view our complete list of solar calculators by state to find your location.