Solar Companies in Fairfield, CA: Who Installed the Most Systems in 2025

Installers who connected the most home solar systems in Fairfield in 2025

Counts from utility records, not a ranking or endorsement. Check each license's status and complaint history on the CSLB's Check a License page (checked Sept. 24, 2026).

Source: California Distributed Generation Statistics (CPUC), Interconnected Project Sites data set, data through May 31, 2026 (checked Sept. 24, 2026).

Home solar in Fairfield by the numbers

PG&E approved 735 home solar systems in Fairfield in 2025, from 80 installers; the top three were named on 44% of them. The busiest year since 2021 was 2023, with 1,402 (2025: -48%). Another 251 were approved from January through May 2026.

2025 mix: 47% leased or on a power purchase agreement, 53% owned by the household; 53% with a battery; median size 5.64 kW DC. Solano County: 49% leased or PPA, 50% with a battery, median 5.64 kW.

Hiring a solar company in Fairfield

Solar companies in Fairfield submit an eligible rooftop design to SolarAPP+, then apply for the City's SolarAPP+ permit and schedule the inspection in BUILD, the City's permit system, with an active Fairfield business license. PG&E delivers the power and MCE supplies the generation; Suisun City next door is not an MCE member. Compare at least three written bids built on your own bill.

Start with your Fairfield electricity bill

Fairfield is one of four Solano County places MCE serves, with Benicia, Vallejo and unincorporated Solano County. A Fairfield bill therefore carries PG&E's delivery charges and MCE's generation charges, and MCE's solar program sets the generation credits: Net Energy Metering for systems applied for by April 14, 2023 and MCE's Solar Billing Plan after that. MCE pays annual surplus at the Net Surplus Compensation rate plus $0.02 per kWh.

Fairfield's SolarAPP+ permit in BUILD

Fairfield runs its automated solar permit in three steps. The contractor registers and submits the design on the SolarAPP+ website, where a processing fee is charged. It then logs in to BUILD, the City's permit system, and applies for a City of Fairfield SolarAPP+ permit with the approval, and finally schedules the inspection in BUILD. An active City of Fairfield business license is required.

Two details are specific to Fairfield. A roof-mount project that is part of a subdivision must first submit its master solar plans to building@fairfield.ca.gov. And the SolarAPP+ program lists Fairfield as accepting solar with storage and main panel upgrades but not main breaker derates, so a design that fits solar onto an existing panel by downsizing the main breaker needs the City's regular review. Fairfield has not filed an annual SB 379 permit report in the Energy Commission's data file.

How MCE credits a Fairfield solar home

MCE enrolls solar customers in its own program automatically. On its Net Energy Metering program, credits build at retail rates and are settled at MCE's annual spring cash-out, which pays surplus at the Net Surplus Compensation rate plus $0.02 per kWh; newer systems are on MCE's Solar Billing Plan for generation and PG&E's for delivery. PG&E still sends the one bill and trues up delivery separately.

The provider changes at the city line. MCE's member list covers Fairfield and unincorporated Solano County but not Suisun City, so two homes a few blocks apart can have different generation providers. Read the provider name on your bill before trusting a proposal's savings figure.

What a Fairfield quote needs to explain

A comparison to ask for

In a newer Fairfield subdivision, ask whether a builder's master solar plan already applies to your home before comparing bids for a different layout. Then have each bidder show the MCE generation credits and PG&E delivery charges its design leaves you with, since the two halves settle on different schedules.

Verify the company behind the Fairfield quote

Match the business name and license number on each Fairfield proposal to the CSLB record, then use our contractor verification steps, the quote comparison guide and the PPA, loan, lease and cash comparison.

Fairfield solar quote questions