San Francisco Solar Quick Facts
| Factor | San Francisco Reality |
|---|---|
| Primary Utility | Pacific Gas & Electric (PG&E) — plus CleanPowerSF for generation, PG&E for distribution |
| Avg. Electricity Rate | 33.75¢/kWh blended; PG&E Tier 2 can exceed 45¢/kWh |
| Peak Sun Hours | 4.2–5.0 hrs/day (highly variable by neighborhood and season) |
| Renter Percentage | ~65% of SF households rent — one of the highest in major US cities |
| Victorian Home Stock | ~48,000 Victorian-era buildings; many have roof complexity that raises installation cost |
| Wind Loads | High — San Francisco's hilltop and oceanfront homes experience elevated wind that requires additional racking engineering |
| Avg. Annual Savings | $1,400–$1,900/year for homes with favorable roof access |
Does the Fog Actually Ruin Solar? (The Real Numbers)
The fog question is the first thing every SF homeowner asks. The honest answer: it matters, but it doesn't disqualify solar — and it varies enormously by neighborhood.
Myth: "San Francisco is too foggy for solar to work."
Reality: SF averages roughly 4.5 peak sun hours/day annually — lower than Fresno's 5.5 or Phoenix's 6.5, but comparable to Portland (4.0) and higher than Seattle (3.5), both of which have robust solar markets. The fog doesn't eliminate solar production — it reduces it, especially in specific neighborhoods and specific months.
The San Francisco Fog Map for Solar
SF's microclimates create dramatic production differences within a 7×7 mile city. Here's what installers know from years of monitoring:
| Neighborhood | Fog Exposure | Peak Sun Hours (Annual) | Relative Solar Viability |
|---|---|---|---|
| Sunset, Parkside, Outer Richmond | Very High — fog belt | 3.8–4.2 hrs/day | Marginal; need careful sizing |
| Inner Sunset, Inner Richmond | High | 4.0–4.4 hrs/day | Viable with right roof orientation |
| Noe Valley, Glen Park, Bernal Heights | Low — fog shadow | 4.6–5.0 hrs/day | Good — among best in SF |
| Mission District, Potrero Hill | Low to Medium | 4.6–4.9 hrs/day | Good production potential |
| Twin Peaks, Diamond Heights | Medium — elevation fog | 4.2–4.6 hrs/day | Moderate; wind is bigger issue |
| Excelsior, Visitacion Valley, Bayview | Low | 4.8–5.1 hrs/day | Best in SF; often overlooked |
| SOMA, Mission Bay, Dogpatch | Low to Medium | 4.5–4.8 hrs/day | Good, but mostly condos/commercial |
The key insight: the fog belt (Sunset/Richmond) genuinely reduces solar production — if you're in these neighborhoods, installers may still quote systems, but you need to scrutinize the production estimates carefully. Noe Valley, Bernal Heights, and the southern neighborhoods get meaningfully more sun and represent SF's best residential solar opportunity.
Summer "Gloom" vs. Winter Clarity
SF's seasonal pattern is the inverse of most US cities. Summer brings marine layer (June–August) that suppresses production significantly in fog-belt neighborhoods. Winter months (November–February) are often clearer, albeit with shorter days. Annual production estimates matter more than peak summer output for ROI calculations in SF.
Victorian Homes and Solar: An SF-Specific Challenge
San Francisco has more Victorian and Edwardian homes than any other US city — roughly 48,000 buildings from the 1880s–1910s. These architectural gems create unique solar installation challenges that drive up cost and complexity.
The Roof Complexity Problem
Victorian homes are characterized by complex, multi-pitched roofs: gabled dormers, steep pitches (often 8/12 to 12/12), ornate cornices, and in some cases, mansard roof sections with near-vertical slopes. Each roof plane transition means fewer contiguous panels and more mounting complexity.
A 6 kW system on a simple ranch house in Concord might use 15 panels in two neat rows. The same 6 kW system on a Victorian in Noe Valley might require 17 panels split across three roof sections, with custom racking on each pitch, additional labor for steep-pitch safety equipment, and more complex wiring runs. That complexity adds $2,000–$5,000 to installation cost compared to simple roofs.
Historic District Restrictions
Some SF Victorian neighborhoods fall under historic preservation guidelines that add review requirements. The Castro, Alamo Square, and portions of the Haight are near designated historic districts. The Department of Building Inspection (DBI) and SF Planning Department may require designs to minimize visual impact from the street. Rear-roof placement is often the only approved configuration — which may reduce system size depending on which roof pitches face the street.
This isn't an absolute barrier, but it adds 4–8 weeks to permitting and may require a pre-application conference with SF Planning. Ask your installer if your specific address has any Planning review requirements before signing a contract.
Roof Condition and Age
Victorian roofs that haven't been updated in the past 15–20 years often need work before solar installation. Common SF issues: deteriorated flat tar-and-gravel sections on lower roofs, aging slate or shingle on main pitches, dry rot in rafters visible from the attic. Solar installers should include a roof condition assessment in their site visit. Installing solar on a roof that needs replacement in 5 years means paying for removal and reinstallation — budget $1,500–$3,000 for that eventuality.
Wind Load Engineering
San Francisco's wind is genuinely intense — especially on hilltops (Twin Peaks, Potrero Hill, Nob Hill, Russian Hill). The San Francisco Building Code requires wind load calculations for solar racking. Installers must specify racking systems rated for SF's wind exposure category. This is not usually a cost driver, but it's worth confirming your installer is using appropriate racking hardware and has pulled proper permits through DBI.
PG&E vs. CleanPowerSF: Understanding SF's Two-Utility System
San Francisco has an unusual utility arrangement that confuses many residents. You likely have two electricity accounts:
- PG&E: Handles electricity distribution (the wires, poles, grid infrastructure) and billing. Net metering interconnection goes through PG&E. You're on PG&E's NEM 3.0 tariff if you installed solar after April 2023.
- CleanPowerSF (SFPUC): San Francisco's Community Choice Aggregation program — handles electricity generation. Most SF residents were auto-enrolled in CleanPowerSF, which sources power from renewable energy. You pay CleanPowerSF's generation rate, not PG&E's.
For solar customers: net metering is processed through PG&E regardless of whether you're a CleanPowerSF customer. Your excess solar flows through the PG&E grid and earns NEM 3.0 export credits at PG&E's avoided cost rates. CleanPowerSF's higher renewable content doesn't change your solar economics — it affects how your imported power is sourced when your panels aren't producing.
Solar for San Francisco Renters: The City's Most Important Solar Topic
With 65% of households renting, solar for renters isn't a niche topic in San Francisco — it's the main topic. The good news: San Francisco has more solar options for renters than almost any other US city.
CleanPowerSF GreenConnect (Community Solar)
CleanPowerSF's GreenConnect program lets renters and homeowners subscribe to a share of community solar installations. You receive credits on your PG&E bill for the solar energy produced by your subscription share. This is the closest thing to "owning solar" without any installation. It's available at no upfront cost and provides genuine renewable energy bill credits. Check availability and current pricing at sfwater.org/cleanpowersf.
Plug-in Balcony Solar
California law is now quite friendly to plug-in solar. AB 2188 (2022) and follow-up regulations limit what landlords can prohibit regarding portable solar equipment. A 400–800W balcony kit from EcoFlow, Anker SOLIX, or similar can legally connect to your apartment's outlet without requiring landlord panel access.
At PG&E rates of 33.75¢+ per kWh, even a 400W system producing 50 kWh/month saves roughly $17–$20/month — $200–$240/year. Payback period: 3–4 years. For a Mission or Noe Valley south-facing balcony with good sun exposure, production will be solid.
One SF-specific tip: many Victorian flat-roof decks (common in the Richmond, Sunset, and Haight areas) provide excellent south or southwest exposure with no shading — sometimes better than the pitched main roof below. A small 200–400W deck-mounted kit is an often-overlooked option for SF renters with deck access.
Multifamily Solar Programs
SF's Green New Deal and related city programs have funded several multifamily building solar projects. If your building has HOA or building management, ask about the SFPUC's Solar for All program and whether your building qualifies for group installation projects. Buildings with 5+ units can apply for separate commercial solar programs with different economics than residential.
Tenant Solar Rights Under California Law
California Civil Code 1940.10 addresses solar energy devices in rental housing. In short: tenants have the right to install portable solar equipment that connects to a standard outlet without landlord permission. For anything requiring roof access or panel installation on building structure, landlord consent is needed — but California law restricts landlords from unreasonably withholding consent for solar installations that don't impair building integrity or aesthetics.
San Francisco Solar Installation Costs and ROI
San Francisco is among the most expensive places in the US to install solar — not because of panels (which are a commodity), but because of labor costs, roof complexity, permitting fees, and the premium for installers experienced with SF's unique building stock.
| System Size | Typical SF Cost | Est. Annual Savings | Payback Period |
|---|---|---|---|
| 3 kW (small/Victorian) | $11,000–$15,000 | ~$700/year | 15–20 years |
| 5 kW (moderate) | $17,000–$22,000 | ~$1,200/year | 14–18 years |
| 7 kW + battery | $30,000–$42,000 | ~$1,800/year | 10–14 years* |
| 10 kW + battery | $40,000–$55,000 | ~$2,200/year | 10–14 years* |
*After SGIP battery rebate where eligible. SF's higher installation costs extend payback periods compared to LA or SD — this is the honest reality of the market.
SF installers with specific experience in Victorian and historic district homes include Luminalt (SF-based, specializes in complex roofs), REC Solar, Sunrun's SF division, and several boutique local companies. Get at least three quotes and confirm each includes a site visit, not just a satellite assessment — Victorian roofs require in-person evaluation.