ElectrifyCalc

2026 · No Federal Tax Credit · NREL + EIA Data

Solar Panels in Washington: Cost, Payback & ROI (2026)

Is solar still worth it in Washington after the 30% federal tax credit expired? These pre-computed estimates use NREL PVWatts production data and current 10.5¢/kWh Washington electricity rates for a typical home using 900 kWh/month.

Section 25D (30% federal solar tax credit) expired December 31, 2025

All numbers below reflect 2026 math with no federal residential credit. State incentives, where applicable, are noted in the section below.

Washington Solar at a Glance

Based on a 900 kWh/month home ($95/mo electric bill at 10.5¢/kWh), 100% offset, no state rebate applied.

System Size

9.8 kW

For 900 kWh/month home

Estimated Cost

$28,964

At $2.95/W (LBNL 2024 avg)

Payback Period

20.9 years

Without state rebate

First-Year Savings

$1,134

Estimated annual savings

25-Year Savings

$36,264

Cumulative before rebate

Net 25-Year Benefit

$7,301

Savings minus system cost

Electricity Rate

10.5¢/kWh

below average vs. 16.0¢ U.S. avg · EIA 2025

Solar Resource

1,100 kWh/kW/yr

limited · 3.4 peak sun hrs/day · NREL PVWatts

Is Solar Worth It in Washington in 2026?

Washington's 10.5¢/kWh rate and relatively modest solar resource (1,100 kWh/kW/year in western Washington; somewhat better east of the Cascades) make it one of the more challenging solar economics in the nation. The state's abundant cheap hydropower — which makes electricity so affordable — is also the reason solar ROI is limited. Eastern Washington homeowners have meaningfully better sun exposure.

For a typical Washington home consuming 900 kWh per month, our calculation shows a 9.8 kW system needed for 100% offset. At the current national average installed cost of $2.95/W (LBNL Tracking the Sun 2024), that's $28,964 gross before any state rebates. Year-one savings of $1,134 grow each year as electricity rates escalate — the model assumes 2.5%/year (EIA AEO 2024).

The 20.9 years payback period is longer than the national average due to low electricity rates or limited solar resource. Over 25 years — the standard warranty period for most premium panels — a Washington homeowner following this profile would save an estimated $36,264 total, for a net benefit of $7,301 after recovering the system cost.

Your state has a low solar resource (1100 kWh/kW/year). Payback periods will be longer than the national average.

Year-by-Year Savings Snapshot: First 10 Years

Based on 9.8 kW system, 0.5%/yr degradation, 2.5%/yr rate escalation, no state rebate.

YearProduction (kWh)Annual SavingsCumulative
Year 110,800$1,134$1,134
Year 210,746$1,157$2,291
Year 310,692$1,180$3,470
Year 410,639$1,203$4,673
Year 510,586$1,227$5,900
Year 610,533$1,251$7,151
Year 710,480$1,276$8,427
Year 810,428$1,301$9,729
Year 910,375$1,327$11,056
Year 1010,324$1,354$12,410

System cost to recover: $28,964. Table shows savings without state rebate applied. Use the interactive calculator to enter your actual bill and any rebate.

Solar Incentives in Washington (2026)

Washington exempts solar from state and local sales tax. Puget Sound Energy and Pacific Power offer net metering at retail rates.

  • Sales tax exemption on solar equipment (RCW 82.08.962)
  • Net metering via PSE and Pacific Power
  • No state solar rebate program currently

Incentive programs change frequently. Verify current offerings at dsireusa.org or directly with your utility before making any purchasing decision.

How We Calculate Washington Solar ROI

These estimates use the same methodology as our interactive solar ROI calculator, applied to Washington-specific data:

System cost

$2.95/W installed

LBNL Tracking the Sun 2024

Solar production

1,100 kWh/kW/yr

NREL PVWatts v8

Electricity rate

10.5¢/kWh

EIA Residential Rates 2025

Rate escalation

2.5%/year

EIA Annual Energy Outlook 2024

Panel degradation

0.5%/year

NREL (Jordan & Kurtz, median)

System lifetime

25 years

Standard warranty period

No Section 25D (federal residential solar credit) is included — it expired December 31, 2025. State incentives are not reflected in these pre-computed figures; use the interactive calculator to enter specific rebate amounts.

Calculate With Your Actual Numbers

The figures above use statewide averages. Enter your actual monthly bill, any Washington rebate amounts, and your offset target in our interactive calculator for a personalized estimate.

Frequently Asked Questions — Solar in Washington

Estimates are based on NREL PVWatts v8 production data, EIA 2025 electricity rates, and LBNL 2024 installed cost benchmarks. Actual savings vary by roof pitch, shading, utility rate structure, and local permit costs. This is not financial advice. Consult a licensed solar installer before making any purchasing decision.