How much electricity does a solar panel system produce in San Francisco?

In San Francisco, each kilowatt of installed solar produces roughly 1,510 kWh per year on a standard south-facing roof at 20° tilt. A 5 kW system yields about 7,549 kWh annually, 7 kW about 10,569 kWh, and 10 kW about 15,099 kWh.

What is the best month for solar in San Francisco?

July is the strongest month, producing about 170 kWh per kW installed. December is weakest at roughly 73 kWh per kW — a seasonal swing of about 2.3×.

Which electricity rate matters most for solar in San Francisco, CA?

PG&E's E-TOU-C is the schedule modelled here. Peak 4–9pm every day, year round. PG&E’s legacy default TOU rate. The export rule matters as much as the price: it decides what a kilowatt-hour sent back to the grid is actually worth.

Is the performance ratio in San Francisco good?

This model gives a performance ratio of 0.802 for San Francisco, meaning 80.2% of the energy landing on the panels reaches the meter as AC. Losses come from cell temperature, inverter efficiency, soiling and wiring.

Home / Solar by city / San Francisco, CA

Solar panels in San Francisco, CA

Every figure below is produced by simulating a full year — 8,760 hours — of sun angles, cloud cover, air temperature and wind for San Francisco, then running the result through a panel and inverter model. No rules of thumb.

1,510kWh per kW / year

10,569kWh from a 7 kW roof

0.802performance ratio

What a system actually produces here

Solar output in San Francisco peaks in July and bottoms out in December, a swing of about 2.3×. That seasonal shape matters more than the annual total if your utility settles exports monthly rather than annually — a big summer surplus can be worth much less than the same energy spread evenly.

Month	Sun (kWh/m²/day)	kWh per kW	7 kW system
Jan	2.2	77	539
Feb	3.1	90	627
Mar	4.4	126	880
Apr	5.9	150	1,047
May	6.7	163	1,142
Jun	7.2	164	1,145
Jul	7.2	170	1,193
Aug	6.4	159	1,115
Sep	5.3	137	962
Oct	3.9	117	818
Nov	2.6	85	593
Dec	2.0	73	510

Electricity rates that shape the payback

What a solar system saves in San Francisco depends less on how much it produces than on when it produces, and what your utility pays for the surplus. These are the CA schedules modelled by the calculator:

PG&E — E-TOU-C

Peak 4–9pm every day, year round. PG&E’s legacy default TOU rate. Fixed charge $24.00/month. Summer Peak $0.52, Off-peak $0.32. Winter Peak $0.40, Off-peak $0.29.
Source: PG&E residential rate plan pricing, effective 1 Mar 2026

PG&E — E-ELEC

The default rate for new PG&E solar customers under net billing. Deep midnight–3pm off-peak. Fixed charge $24.00/month. Summer Peak $0.55, Part-peak $0.39, Off-peak $0.33. Winter Peak $0.32, Part-peak $0.30, Off-peak $0.28.
Source: PG&E residential rate plan pricing, effective 1 Mar 2026

Southern California Edison — TOU-D-PRIME

What new SCE solar and storage customers are put on. No baseline credit; $24.15/mo basic charge. Fixed charge $24.15/month. Summer On-peak $0.60, Mid-peak $0.43, Off-peak $0.27. Winter On-peak $0.52, Mid-peak $0.46, Off-peak $0.29.
Source: SCE Schedule TOU-D-PRIME; Base Services Charge from Nov 2025

SDG&E — TOU-DR1

The highest residential prices in the continental US. On-peak 4–9pm daily. Fixed charge $24.15/month. Summer On-peak $0.70, Off-peak $0.48, Super off-peak $0.39. Winter On-peak $0.62, Off-peak $0.54, Super off-peak $0.45.
Source: SDG&E Schedule TOU-DR1 total rates table, effective 1 Jan 2026

Export rule: PG&E — net billing — exports earn the hour-by-hour avoided-cost value rather than retail, which in the middle of a sunny afternoon is a small fraction of it. PG&E — net billing — exports earn the hour-by-hour avoided-cost value rather than retail, which in the middle of a sunny afternoon is a small fraction of it. Southern California Edison — net billing — exports earn the hour-by-hour avoided-cost value rather than retail, which in the middle of a sunny afternoon is a small fraction of it. SDG&E — net billing — exports earn the hour-by-hour avoided-cost value rather than retail, which in the middle of a sunny afternoon is a small fraction of it. Under net billing, exported kilowatt-hours earn far less than the retail price you pay to import them — which is why self-consumption and batteries change the maths so much. The calculator settles every hour individually rather than netting annually.

Run your own numbers

Payback depends on what you pay for the system, how much power your household uses after dark, and which incentives you qualify for — none of which a city page can know. The calculator asks for those and settles all 8,760 hours against your actual rate.

Open the payback calculator →

See also: solar incentives in California — the state credit, the export rules, and what the §25D expiry changed for buyers here.

Other cities

Method

Irradiance is decomposed into beam and diffuse components and projected onto the array plane with the Perez model, with incidence-angle losses, a cell-temperature model driven by air temperature and wind, and an inverter efficiency curve including clipping. Annual yield is checked against NREL PVWatts v8 across all 18 modelled cities; RMS error is 2.70%. See the glossary for what each term means.