Solar in Spokane, WA: 2026 Cost, Savings & Payback

Calculate 2026 solar panel cost, payback, and 25-year bill savings in Spokane, Washington. Based on 3.1 peak sun hours/day, 10.3¢/kWh average electricity rate, Avista Utilities utility context, and current IRS guidance for the ended federal residential clean energy credit.

Solar in Spokane, WA: quick answer

A typical 6kW solar system in Spokane costs about $16,440 before local or state incentives. For 2026 installs, the federal residential clean energy credit is modeled as $0, so the estimated cost remains about $16,440 before any local incentive. It produces about 5,431 kWh per year from 3.1 peak sun hours/day, saves about $558 per year, and reaches payback in about 29.5 years.

2026 6kW Cost

$16,440

Monthly Savings

$47

Production / kW

905 kWh

Panel Count

~15

3.1

Peak Sun Hours/Day

10.3¢

Avg Rate (¢/kWh)

29.5 yr

Payback Period

$19k

25-Year Savings

Spokane Solar Overview

Population:228,989
Sunny Days/Year:160
Avg Temperature:50.6°F
Solar Penetration:1.7%
Utility Company:Avista Utilities
Net Metering:Available

Calculate Your Spokane Solar Savings

3 kW15 kW

Spokane average: $122/mo

South-facing roofs produce the most energy

Add $8,000-$12,000 for whole-home battery backup

Annual Production

5,431

kWh/year

Annual Savings

$558

per year

Net System Cost

$16,440

after 2026 federal credit

Payback Period

29.5 yr

break-even time

Bill Offset and Export Assumptions

Current Annual Bill

$1,464

Estimated Usage

14,241 kWh

Bill Offset

38%

Used On Site

100%

Exported production is discounted in this planning model instead of being treated as a guaranteed one-for-one bill credit. For Spokane, verify the current Avista Utilities export-credit method and any fixed monthly charges before relying on the payback number.

25-Year Total Savings

$19,060

Monthly Savings

$47

2026 Federal Credit

$0

Cumulative Savings vs System Cost

$0k$5k$10k$15k$20kYr 0Yr 5Yr 10Yr 15Yr 20Yr 25System Cost
Cumulative Savings System Cost

Cost Breakdown

ItemSpokaneNational Avg
Gross System Cost (6kW)$16,440$17,100
2026 Federal Residential Credit-$0$0
Net System Cost$16,440$17,100
Cost Per Watt$2.74/W$2.85/W

Solar Potential in Spokane

Sun Hours vs National Average

3.1 hrs
4.5 hrs

Spokane gets 31% less sun than the national average, but high-efficiency panels compensate.

Climate Advantages

  • 160 sunny days per year
  • Average temperature: 50.6°F — cooler temps actually improve panel efficiency
  • Average roof size: 1,847 sq ft — enough for a 102-panel system

Spokane Solar Incentives & Programs

Federal Investment Tax Credit (ITC)

For 2026 planning, JouleIO does not subtract a federal residential clean energy credit. The IRS says the Residential Clean Energy Credit was 30% for eligible property installed from 2022 through December 31, 2025, and is not available for property placed in service after December 31, 2025.

Source: IRS Residential Clean Energy Credit and IRS One Big Beautiful Bill provisions.

Washington State Incentives

Washington sales tax exemption for solar; net metering at retail rate

Net Metering — Avista Utilities

Avista Utilities offers net metering in Spokane. Earn credits for excess solar energy sent to the grid, reducing your electric bill further.

Environmental Impact in Spokane

2.3

Tons CO2 Offset/Year

37

Equivalent Trees Planted

0.5

Homes Worth of Energy

Based on 5,431 kWh annual production with a 6kW system. EPA average: 0.417 metric tons CO2 per MWh, 10,632 kWh per US home.

Solar Energy in Spokane, Washington

Spokane, Washington receives an average of 3.1 peak sun hours per day, which, while below the national average, still makes solar a viable option with modern high-efficiency panels. With electricity rates averaging 10.3¢ per kWh from Avista Utilities, below the national average, but with rates rising 2-3% annually, the long-term savings are still meaningful.

A typical 6kW solar system in Spokane produces approximately 5,431 kWh per year, saving homeowners an estimated $558 annually. The system pays for itself in about 29.5 years, after which you enjoy essentially free electricity for the remaining -4+ years of the system's warranty life.

Spokane has a solar penetration rate of 1.7% — indicating early-stage solar adoption with tremendous growth potential as prices continue to fall. The cost of living index of 107 (national average: 100) is near the national average.

Other Cities in Washington

Methodology & Solar Data Sources for Spokane

How we calculate Spokane solar potential and savings: Solar production estimates use NREL's PVWatts calculator methodology, applied to Spokane's specific solar irradiance (peak sun hours), tilt angle, and azimuth. Cost figures combine NREL's Annual Technology Baseline for system pricing, ENERGY STAR's database for residential PV averages, and EIA Form 861 utility rate data for Washington.

  1. Solar irradiance for Spokane: based on NREL National Solar Radiation Database (NSRDB) — 30-year average peak sun hours per day.
  2. System sizing assumes residential rooftop installation with standard 350-400W panels, calibrated to typical Spokane household electricity usage.
  3. Federal tax credit: modeled as 0% for 2026 residential installations because IRS guidance says the Residential Clean Energy Credit is not available for property placed in service after December 31, 2025.
  4. Net metering assumes 1:1 retail-rate compensation typical in Washington (verify with local utility — some have shifted to net billing or avoided-cost rates).
  5. System lifetime standard 25 years with annual degradation of 0.5%/year per industry warranty norms.

Authoritative US solar data sources:

Solar Disclaimer: Solar savings vary based on roof orientation, shading, system quality, installer markup, financing terms, utility rate plan, and policy changes. Always get 3+ quotes from NABCEP-certified installers and review contracts carefully. Tax credit eligibility depends on tax liability — consult a tax professional.

Reviewed by Brazora Monk · Last updated 2026 · NREL irradiance data per NSRDB latest release

Frequently Asked Questions

How much do solar panels cost in Spokane, WA?

The average cost of a 6kW solar panel system in Spokane is approximately $16,440 before local or state incentives ($2.74/watt). For 2026 planning, this calculator does not subtract a federal residential clean energy credit because IRS guidance says the credit is not available for property placed in service after December 31, 2025. Washington sales tax exemption for solar; net metering at retail rate

How many solar panels do I need in Spokane, WA?

A typical 6kW residential solar system in Spokane needs about 15 panels if each panel is rated near 400 watts. That system produces about 5,431 kWh per year in this estimate, or roughly 905 kWh per installed kW before shading, roof orientation, and inverter losses are customized.

How many peak sun hours does Spokane get?

Spokane, WA receives an average of 3.1 peak sun hours per day and approximately 160 sunny days per year. While below the national average, solar panels can still provide significant savings due to advancing panel technology.

What is the solar payback period in Spokane?

The average solar payback period in Spokane is approximately 29.5 years for a 6kW cash-price estimate before local or state incentives. After payback, your solar panels generate essentially free electricity for the remaining warranty life. Over 25 years, bill savings can reach about $19,060 before subtracting installation cost.

Does Spokane have net metering?

Yes, Spokane has access to net metering through Avista Utilities. This allows you to earn credits for excess solar energy sent to the grid, but the final savings depend on the current utility tariff and fixed monthly charges.

Is solar worth it in Spokane, WA in 2026?

Solar may still be worthwhile in Spokane, especially for homeowners with high usage or strong local incentives, but the 29.5-year payback means quote comparison matters. For 2026 installs, JouleIO does not assume a federal residential credit; local incentives and net metering are the main financial drivers.

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