Washington County, IL solar installation & market data
Updated September 21, 2026Provisional score · under 500 installs By The SolarDNA Data Team
Washington County has 240 solar installations across 9 zip codes, installations up 21.7% over the trailing twelve months, and an installs-weighted Market Score of 41.
Active installations
240
Zip markets
9
Median cost
—
12-mo growth
▲ 21.7%
Installers active
30
County Market Score
Good · installs-weighted across 9 zips
Best zip in Washington County scores higher than 45% of U.S. zip markets.
Versus Illinois
How Washington County compares with the state
Installed cost
—
state median $6.56/W
Market score
41 vs 43
Illinois scores 43
Share of state installs
0.21%
of 112.7K tracked statewide
Battery attach
0.0%
state 0.0%
Statewide momentum
▲ 23.1%
residential solar added in Illinois, 12 months through Jul 2026
Statewide market
136.9K systems
4.0% of homes · utility-reported through Jul 2026
Next-12-month outlook: 55–69 installs (midpoint 62)
Trailing-12-month installs carried forward at half the observed growth rate (capped at ±30%), with a ±11% band. Not a forecast of permits or policy.
Growth & pricing
Washington County by year
56 installs in the trailing twelve months vs 46 before
Installations by year
Median installed cost, $/W DC by year
Installer comp set
Who installs in Washington County
Summed across every zip in the county
| # | Installer | Installs | 12-mo | Zips | $/W |
|---|---|---|---|---|---|
| 1 | OFF GRID ENERGY SOLUTIONS | 10 | 10 | 5 | — |
| 2 | SUPPLIED ENERGY | 9 | 3 | 3 | — |
| 3 | FREEDOM FOREVER | 8 | 8 | 4 | — |
| 4 | EFS ENERGY | 7 | 0 | 1 | — |
| 5 | LGCY POWER | 7 | 5 | 3 | — |
| 6 | ABSOLUTE CLIMATE D B A C H ELECTRIC | 7 | 1 | 2 | — |
| 7 | CR SOLAR | 5 | 5 | 3 | — |
| 8 | STRAIGHTUP SOLAR | 4 | 3 | 3 | — |
| 9 | SOLARSHIPS INSTALLATION SERVICES | 3 | 3 | 3 | — |
| 10 | REVOLUTION ENERGY SYSTEMS | 2 | 1 | 2 | — |
| 11 | MISSOURI SUN SOLAR | 2 | 0 | 2 | — |
| 12 | GENERAL ENERGY | 2 | 2 | 1 | — |
| 13 | OFF GRID ENERGY SOLUTIONS DBA AVEYO | 2 | 1 | 1 | — |
| 14 | SUNVOLT SOLAR | 2 | 1 | 1 | — |
| 15 | SUN SOLAR ILLINOIS | 2 | 0 | 1 | — |
| 16 | GOODPWR | 2 | 2 | 1 | — |
| 17 | STRAIGHT UP SOLAR | 2 | 1 | 1 | — |
| 18 | SUN SOLAR | 2 | 1 | 2 | — |
| 19 | A&I ELECTRIC | 2 | 1 | 1 | — |
| 20 | SOLIS ENERGY SERVICES | 2 | 0 | 2 | — |
| 21 | ASTRAWATT SOLAR | 2 | 0 | 2 | — |
| 22 | CONTEMPORARY CONTRACTING | 1 | 0 | 1 | — |
| 23 | AG TECHNOLOGIES | 1 | 0 | 1 | — |
| 24 | MARTIN SOLAR | 1 | 1 | 1 | — |
| 25 | HELIO SOLAR POWER | 1 | 0 | 1 | — |