Castro Valley, CA solar installation & market data
Updated April 21, 2026 By The SolarDNA Data Team
Castro Valley has 4,364 solar installations across 2 zip codes at a median installed cost of $4.54/W, installations up 24.3% over the trailing twelve months, and an installs-weighted Market Score of 52.
Active installations
4,364
Zip markets
2
Median cost
$4.54/W
12-mo growth
▲ 24.3%
Installers active
355
City Market Score
Excellent · installs-weighted across 2 zips
Best zip in Castro Valley scores higher than 98% of U.S. zip markets.
Versus California
How Castro Valley compares with the state
Installed cost
$0.27/W above
state median $4.26/W
Market score
52 vs 53
California scores 53
Share of state installs
0.19%
of 2.3M tracked statewide
Battery attach
13.9%
state 12.7%
Statewide momentum
▲ 1.1%
residential solar added in California, 12 months through Jul 2026
Statewide market
2.3M systems
30.9% of homes · utility-reported through Jul 2026
Next-12-month outlook: 302–386 installs (midpoint 344)
Trailing-12-month installs carried forward at half the observed growth rate (capped at ±30%), with a ±12% band. Not a forecast of permits or policy.
Growth & pricing
Castro Valley by year
307 installs in the trailing twelve months vs 247 before
Installations by year
Median installed cost, $/W DC by year
Installer comp set
Who installs in Castro Valley
Summed across every zip in the city
| # | Installer | Installs | 12-mo | Zips | $/W |
|---|---|---|---|---|---|
| 1 | SUNRUN | 789 | 87 | 2 | $4.55 |
| 2 | TESLA | 749 | 28 | 2 | $5.11 |
| 3 | SUNPOWER | 247 | 0 | 2 | $4.53 |
| 4 | SEMPER SOLARIS | 156 | 7 | 2 | $4.24 |
| 5 | SYNERGY POWER CA | 143 | 0 | 2 | $3.73 |
| 6 | YOUR ENERGY SOLUTIONS | 99 | 7 | 2 | $3.82 |
| 7 | PETERSENDEAN | 91 | 0 | 2 | $3.83 |
| 8 | THE SOLAR COMPANY | 87 | 0 | 2 | $6.25 |
| 9 | HIGH DEFINITION SOLAR | 71 | 0 | 2 | $7.62 |
| 10 | BETTER EARTH | 70 | 0 | 2 | $4.66 |
| 11 | BRIGHT OPS | 60 | 28 | 2 | $7.06 |
| 12 | SUNGEVITY | 56 | 0 | 2 | $3.75 |
| 13 | SOLAR OPTIMUM DESIGN ELECTRIC | 51 | 0 | 2 | $3.02 |
| 14 | HOOKED ON SOLAR | 48 | 2 | 2 | $4.35 |
| 15 | KOTA CONSTRUCTION | 46 | 0 | 2 | $5.60 |
| 16 | INFINITY ENERGY | 45 | 0 | 2 | $5.06 |
| 17 | FREEDOM FOREVER | 45 | 9 | 2 | $5.18 |
| 18 | EMPOWER ELECTRIC | 44 | 0 | 2 | $5.30 |
| 19 | SOLAR TECHNOLOGIES | 34 | 2 | 2 | $4.43 |
| 20 | NRG CLEAN ENERGY | 34 | 0 | 2 | $3.34 |
| 21 | CENTURY ROOF AND SOLAR | 33 | 0 | 2 | $4.75 |
| 22 | NEXUS ENERGY SYSTEMS | 29 | 5 | 2 | $5.02 |
| 23 | CLEAN SOLAR | 28 | 2 | 2 | $4.13 |
| 24 | SIERRA ROOFING AND SOLAR | 22 | 0 | 2 | $4.29 |
| 25 | RIKETY VENTURES | 21 | 0 | 2 | $4.16 |