Solar Panel Cost Calculator El Cajon, CA
See what a solar system costs installed in El Cajon, sized from your power bill. Free, instant, no sign-up.
Updated · installer rankings recalculated
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| System | Installed cost |
|---|
Christian Roofing, IncPremium
4.9 · 188 reviews · Free quote
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Johnson Solar - San Diego County's Best Veteran Owned Solar Installation Company
4.9 · 125 reviews · Free quote
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Sunlight Solar, Inc.
4.5 · 120 reviews · Free quote
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An estimate, not a quote. Based on $2.14–$2.90 per watt installed in California and 1,677 kWh per kW a year in California. Installers confirm the final price after a roof check.
Top-rated solar panel companies in El Cajon
Ranked by TrustAnalytica from verified reviews · see the full Top 10 list →
Christian Roofing, Inc
Licensed in roofing, electrical, and building, Christian Roofing specializes in roofing and solar installations throughout San Diego. Their team handles repairs, replacements, skylight and solar tube installation, and maintenance, often praised for clear communication and careful cleanup. Some customers note occasional delays and specific leak issues after repairs.
Johnson Solar - San Diego County's Best Veteran Owned Solar Installation Company
Johnson Solar is a veteran-owned company specializing in solar panel and battery backup installations, led by a retired Navy aviator with extensive construction experience. The team handles projects of all sizes with clear communication and punctual service, though some customers have noted occasional issues with subcontractor scheduling. Clients appreciate their hands-on approach and thorough… more...
Johnson Solar is a veteran-owned company specializing in solar panel and battery backup installations, led by a retired Navy aviator with extensive construction experience. The team handles projects of all sizes with clear communication and punctual service, though some customers have noted occasional issues with subcontractor scheduling. Clients appreciate their hands-on approach and thorough updates throughout the process.
Sunlight Solar, Inc.
Sunlight Solar, Inc. offers upfront pricing and a no-surprise policy that customers appreciate when installing solar panels and energy-efficient home upgrades. Their team handles everything from solar system installation to roofing and window replacements, with many clients noting careful attention to detail and clear communication throughout the process. Some have mentioned occasional issues… more...
Sunlight Solar, Inc. offers upfront pricing and a no-surprise policy that customers appreciate when installing solar panels and energy-efficient home upgrades. Their team handles everything from solar system installation to roofing and window replacements, with many clients noting careful attention to detail and clear communication throughout the process. Some have mentioned occasional issues with electrical outlets after installation, but overall, the crew is described as respectful and responsive.
How this El Cajon solar cost calculator works
This calculator sizes a solar system from your electricity use. Your monthly bill, divided by the average California electricity price, gives your yearly use; California's sunshine (1,677 kWh per kW of panels a year) then gives the system size that covers it, adjusted for roof direction and shade. The installed price is that size multiplied by the price per watt homeowners in California pay installers. Payback compares that price with what the panels save at California power prices, assuming prices rise 3% a year.
California numbers this calculator uses
- Installed price
- $2.14–$2.90 per watt in California (typical $2.52), before rebates. A typical 6 kW home system costs $12,800–$17,400.
- Sunshine
- 1,677 kWh of electricity per kW of panels a year in California.
- Electricity price
- About 33.3¢ per kWh, the average residential price in California.
- Selling power back
- Power you send to the grid earns less than the price you pay for it (net billing or avoided-cost credits), so using your solar power at home is worth more.
- Rebates and tax credits
- California's net billing (NEM 3.0) pays only a few cents for exported power, so many installers pair panels with a battery. The 30% federal tax credit for buying solar ended for systems installed after December 31, 2025. Leases and power purchase agreements can still carry a federal credit through the installer for systems in service by the end of 2027.
An estimate, not a quote. Roof size and pitch, shading, equipment, permits and the installer all change the final price; installers confirm it after a site visit. Sources: EnergySage state installed-cost data (2026), NREL PVWatts, U.S. Energy Information Administration residential prices (2026), state program pages.