Measured Solar Data for Los Angeles Research by Cali Energy
How rooftop solar actually performs in the Los Angeles area: yearly and monthly production per kW, output by system size, how far production drops in winter, how much it changes from year to year and where the electricity goes in homes with full metering. Measured on 264 rooftop systems on two monitoring platforms over 772 complete system-years, 2019–2025, plus 117 homes with consumption meters and 28 home batteries — not models, not manufacturer claims.
Solar production & seasonality
Real-World Solar Production in Los Angeles
How much electricity rooftop solar really produces per kW on two monitoring platforms, year by year and area by area, and how it compares with the PVWatts model.
Monthly Solar Production in Los Angeles
The normal range for every month, kWh per day, and a check for your own system.
How Much Does a 4–12 kW Solar System Produce?
Yearly, monthly, daily and per-panel output by system size on two platforms, and the size for 1,000–2,000 kWh a month.
Does Solar Produce Less Near the Coast in Los Angeles?
Measured output by area, from the beach cities to the Santa Clarita Valley, and what May Gray and June Gloom really cost.
How Much Does One Solar Panel Produce per Day?
Measured panel by panel: daily output by month, by panel wattage, and why real roofs fall short of the calculator.
How Much Do Solar Panels Produce on Cloudy and Rainy Days?
Output on clear, cloudy, overcast and rainy days, measured day by day against each roof’s own clear-day output.
Was It the Weather or My System?
A daily index of LA rooftop output since 2022: look up any date, the darkest storms, October 2024 and a rule for when to call.
How Much Output Do Dirty Solar Panels Lose in LA?
Clear-day output before and after every rain since 2022, the cost of a dry year, and the ash of January 2025.
How Much Did LA Heat Waves Cut Rooftop Solar Output?
Hot clear days against mild clear days on the same roofs: the loss per 10 °F, every heat wave since 2022, and what a year of heat costs.
Did Wildfire Smoke Cut Rooftop Solar Output in LA?
The January 2025 fires day by day, roofs that went dark when the grid did, the ash and the first rain, and every hazy day since 2022.
How Much Does Solar Production Drop in Winter?
December versus June on the same systems, dark days per winter, rainy against dry winters, and why real roofs fall below the model.
Long-term system performance
Why Did My Solar Production Drop This Year?
Year-to-year change on the same systems on two platforms, checked against two sunlight sources, the output that didn't come back, and a tool.
How Fast Do Solar Systems Lose Output?
Sunlight-corrected output on the same roofs over five to nine years, compared with NREL field data, and the dips every system shared.
Equipment
Energy flows & batteries
How Much Solar Does a Home Actually Use?
Where solar went and where electricity came from in fully metered homes, by season and system size, and what a battery changes.
How Much Electricity Do Solar Homes Still Buy From the Grid?
Purchases and exports month by month, by system size and utility, the night on sunny days and the running balance before an SCE true-up.
Home Electricity Use by ZIP Code in LA County's SCE Areas
SCE's published averages for every ZIP it serves in the county: monthly kWh, summer peaks, trend since 2023, solar share and kW to match.
How Much Electricity Do LA Homes With Solar Actually Use?
Whole-house use measured at the meter: by month, by area, against the state average and on hot days.
Do Homes Use More Electricity After Going Solar?
The same homes in their first, second and third year with solar, adjusted for weather, and what could be behind the rise.
What Share of a Home's Electricity Does Solar Cover?
Annual offset measured at the meter: how many homes reach 100%, by utility and month, and what 100% does and does not mean.
What Was LA Home Solar Output Worth?
Measured kWh per kW at SCE and LADWP average prices since 2020, and the share of output each netting rule counts at retail.
How Many Cycles a Year Does a Home Battery Really Do?
Measured cycles by mode, utility and season, energy returned, the standing draw of a backup battery and warranty headroom.
Is a 13.5 kWh Home Battery Too Big?
Daily surplus and evening need measured in homes without a battery: how much of a 5, 10, 13.5 or 20 kWh battery would be used.
Monitoring & service
Why Is One Solar Panel Producing Less Than the Others?
Panel-by-panel output on roofs with microinverters: what spread is normal, three patterns, and a check for your own panels.
Solar App Says Offline or Shows an Alert?
What an offline app means for production, how long gaps in monitoring data last, and what SolarEdge alerts say.
What an Inverter Failure Costs, and What a Repair Restores
Production before, during and after verified inverter replacements, and how long the warranty process took.
Market & permits
Did NEM 3.0 Turn Solar Panels West?
Direction and tilt of every SCE-area home system in LA County since 2020, by tariff, battery and city.
Which Inverters Do LA Solar Homes Get?
Inverter, battery and panel brands on every SCE-area home system in LA County since 2010, owned and leased.
Are Eaton and Palisades Fire Rebuilds Going Solar?
Rebuild stages and solar permits on every burned Altadena lot since the fire, batteries, and an early Palisades signal.
Do Homes With Solar Need a New Roof Sooner?
Re-roof permits in the years before and after going solar on 11,000 City of LA homes, against similar homes without solar.
How Often Does Going Solar Require a Main Panel Upgrade?
Main panel upgrades on 24,000 county solar installs, by year, battery, tariff period and system size.
Residential Solar Permits in Unincorporated LA County, 2020–2026
How many homes file for solar each month, how many add a battery, how fast permits are issued and how many reach final inspection.
Solar by place
Measured output of the systems Cali Energy installed and monitors, place by place.
How Much Do Solar Panels Produce in Chatsworth?
Six monitored systems in Chatsworth, month by month and against the rest of the Valley.
How Much Do Solar Panels Produce in Encino?
Five monitored systems in Encino, month by month and against the rest of the Valley.
How Much Do Solar Panels Produce in North Hills?
Six monitored systems in North Hills, month by month and against the rest of the Valley.
How Much Do Solar Panels Produce in North Hollywood?
10 monitored systems in North Hollywood, month by month and against the rest of the Valley.
How Much Do Solar Panels Produce in Northridge?
10 monitored systems in Northridge, month by month and against the rest of the Valley.
How Much Do Solar Panels Produce in Porter Ranch?
19 monitored systems in Porter Ranch, month by month and against the rest of the Valley.
How Much Do Solar Panels Produce in Santa Clarita?
11 monitored systems in Santa Clarita, month by month and against the San Fernando Valley.
How Much Do Solar Panels Produce in Simi Valley?
Five monitored systems in Simi Valley, month by month and against the San Fernando Valley.
How Much Do Solar Panels Produce in Tarzana?
Five monitored systems in Tarzana, month by month and against the rest of the Valley.
How Much Do Solar Panels Produce in Winnetka?
Five monitored systems in Winnetka, month by month and against the rest of the Valley.
How Much Do Solar Panels Produce in Woodland Hills?
Eight monitored systems in Woodland Hills, month by month and against the rest of the Valley.
Coming next
- Monitoring & service: how to tell a monitoring glitch from lost production.
About the data
The data come from the monitoring accounts of real customer systems: monthly totals from SolarEdge inverters and daily readings from Enphase microinverters, production meters, consumption meters and batteries, and from public records: state interconnection data, SCE’s ZIP-code usage reports, LA County and City of Los Angeles permits and federal price data. Every study states how many systems and years it uses, what was excluded and why, and the date it was last updated. Aggregated tables are free to reuse under CC BY 4.0 with a link to the study.
Cali Energy is a licensed contractor (CSLB #1032379: B, C-10, C-39) based in Northridge. We design, install and service solar, battery and roofing systems across Los Angeles and Ventura counties.
Projects and service behind the data
The data come from systems like these.
Prepared by Cali Energy, October 15, 2026. Figures describe systems in our monitoring fleet and are not a guarantee of what any specific roof will produce; orientation, tilt, shade, equipment and weather change results. Not engineering, financial or utility advice. See our Content Disclaimer.