Solar Panel Cost in Danville, CA (2026): $4.23/W Reported

Danville homeowners who bought their own solar systems reported a median of $4.23 per watt between January 2025 and May 2026, across 149 systems. The middle half paid $2.90 to $5.52 per watt.

An 8.34 kW system, the median size connected in Danville in 2025, comes to about $35,300 at that median, or $24,200 to $46,000 across the middle half.

Those are reported costs, not a quote, and no federal credit comes off a Danville system finished in 2026: 26 U.S.C. §25D does not cover one whose installation is completed after December 31, 2025 (state and federal rules).

Median reported cost: $4.23/W; Danville addresses, 149 systems
Middle half: $2.90 to $5.52/W; 25th to 75th percentile
Typical 8.34 kW system: $35,300; 8.34 kW × $4.23/W, before any incentive
Same system, middle half: $24,200 to $46,000; size: Danville addresses, 2025 median

Source: California Distributed Generation Statistics (CPUC), Interconnected Project Sites data set, data through May 31, 2026, checked September 24, 2026. Homeowner-owned, solar-only systems of 1 to 25 kW; leases, PPAs and battery systems are left out (method). The CPUC notes these costs are not verified by the government.

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What a solar permit costs in Danville

Danville does not publish a dollar figure for a residential solar permit. Whatever it charges, Government Code §66015 limits a city to $450 for a home system up to 15 kW, plus $15 per kW above that, unless it adopts a written finding that its cost is higher.

What Danville publishes: The Town's SolarApp+ Submittals page says "A processing fee from SolarAPP+ and Town of Danville permit fees will be charged" but does not specify a dollar amount for either fee.
How to file: Yes, explicitly: the page is titled "SolarApp+ Submittals" and states SolarAPP+ "is designed to provide a code-compliance check for the majority of residential, roof-mounted, retrofit photovoltaic systems."
Automated permit platform: SolarAPP+

Sources: Town of Danville SolarApp+ Submittals page, checked September 18, 2026; Gov. Code §66015, checked September 24, 2026. Danville in the California Solar Cost Index sets this fee beside every other city's.

Solar in Danville: installs, leases and batteries

Home solar systems connected at Danville addresses: 484 in 2021, 676 in 2022, 655 in 2023, 304 in 2024 and 397 in 2025. So connections peaked in 2022 and 2025 ran 41% below that peak. Another 177 were connected from January to May 2026.

Of the 397 systems connected in Danville in 2025, 26% were leased or on a PPA, so a solar company owns them, and 74% belonged to the homeowner. 65% had a battery, more often than the 55% statewide. The median Danville system was 8.34 kW, and 82 companies connected at least one.

Danville beside Contra Costa County and Statewide, 2025
	Danville	Contra Costa County	Statewide
Systems connected in 2025	397	6,343	145,404
Leased or on a PPA	26%	43%	45%
With a battery	65%	58%	55%
Median system size	8.34 kW	6.48 kW	6.15 kW
Median reported cost	$4.23/W (149)	$4.09/W (2,573)	$4.14/W (58,628)
Companies connecting systems	82	310	2,475

Source: CPUC DG Stats, data through May 31, 2026. Counts are home systems given permission to operate each year; a city means the service city on the application.

Your utility: PG&E

Danville is billed by Pacific Gas and Electric Company (PG&E). PG&E's average residential rate is 33.7¢/kWh (June 2026 (unchanged since March 2026); rate tracker).

MCE (Marin Clean Energy) supplies generation for many Danville addresses while PG&E delivers and bills; your bill shows which.

Before you sign

In Danville the middle half of reported costs spans $2.90 to $5.52 per watt, and roof, panel work, equipment and contract terms explain most of that gap. California Solar Tax and Permit Rules for 2026 covers them, and the tax, lease and disclosure rules a Danville contract follows.

Frequently asked questions

How much does solar cost in Danville?

About $35,300 for an 8.34 kW system, at the $4.23 per watt median that Danville owners reported (149 systems, January 2025 to May 2026; middle half $2.90 to $5.52). Source: CPUC DG Stats. No federal credit applies to a Danville system finished in 2026.

What does a solar permit cost in Danville?

Danville states no single current figure (no figure published, checked September 18, 2026); Gov. Code §66015 caps it at $450 up to 15 kW unless the city adopts a written finding.

Which utility serves Danville?

Pacific Gas and Electric Company (PG&E). Its average residential rate is 33.7¢/kWh, as of June 2026 (unchanged since March 2026).

Sources

California Distributed Generation Statistics (CPUC), Interconnected Project Sites data set, data through May 31, 2026 — checked September 24, 2026
CPUC, California Solar Consumer Protection Guide — checked September 24, 2026
26 U.S.C. §25D(h) and (e)(8)(A), residential clean energy credit — checked September 24, 2026
Danville solar permitting — Town of Danville SolarApp+ Submittals page — checked September 18, 2026
California Government Code §66015(a), residential solar permit fees — checked September 24, 2026
PG&E average residential rate — CPUC Public Advocates Office, Q2 2026 Electric Rates Report, p.8, 20 — checked November 9, 2026

The tax, contract and permit rules every California city shares, with their statutes: California Solar Tax and Permit Rules for 2026.