West Hills, CA · November – December 2023 · LADWP / LADBS
A new accessory dwelling unit, switched on in fourteen days.
Twenty-nine by thirty-seven feet of new detached dwelling, built under state ADU law and certified for occupancy. The solar on it went from application to permission to operate in two weeks.
On this project a 2.28 kilowatt AC-CEC array on a new, separately metered accessory dwelling unit reached permission to operate fourteen days after the application was filed. The utility reviewed, confirmed and closed the site assessment on the day of filing.
At a glance
- System
- 2.28 kW AC-CEC
- Dwelling
- New detached ADU, 29 × 37 ft
- Application to PTO
- Fourteen days
- Modules
- Mission Solar
- Inverters
- Enphase IQ8M, one per module
- Combiner
- Enphase IQ Combiner 4
- Roof
- Composition shingle
- Utility / AHJ
- LADWP / LADBS
The story
The building came first: a new detached accessory dwelling unit, twenty-nine feet by thirty-seven, permitted under state ADU law and city code and carried through to a certificate of occupancy. A separate building with its own service.
The array on it is small — 2.28 kilowatts AC-CEC, Mission Solar modules with an Enphase IQ8M microinverter under each one, landing in an IQ Combiner on the wall. It sits along one plane of the new roof, with every attachment flashed into fresh shingle courses.
What is worth recording is the calendar. The interconnection application was filed on the thirtieth of November 2023 and the utility fee was paid the same day. The review was completed and confirmed that day, and the site evaluation closed with it. The installation cleared the building department, the utility completed its interconnection review, and permission to operate came through on the fourteenth of December.
Fourteen days, filing to switch-on. Whether another project moves at that pace depends on things this one did not have to deal with — a service that needs upgrading, more than one tenant behind the meter, a site the utility wants to assess in person. LADWP sets out what an interconnection request has to carry, including the plot plan and load schedule an accessory dwelling unit needs.
Worth having in mind if you are adding solar to an older house: there the utility is looking at a service that may be decades old, a panel that may or may not take the connection, and a roof that may have been through two coverings. None of that applied here, which is a difference in the work, not a promise about the calendar.
A 2.28 kilowatt array will not run a household. It was sized for this unit and it sits behind this unit's meter, which is what the interconnection is written against — not the lot it stands on.
How it ran
| 2022 | Building permit for a new detached accessory dwelling unit, 29 × 37 ft |
|---|---|
| 2023 | Certificate of occupancy issued for the unit |
| 30 November 2023 | Interconnection application filed; utility fee paid; review confirmed and site evaluation closed the same day |
| December 2023 | Building department release; utility interconnection review completed |
| 14 December 2023 | Permission to operate |
The building had to exist and be occupiable before its solar could be connected; once it did, the interconnection took two weeks.
What we did
- Sized the array to the accessory dwelling unit rather than to the property.
- Installed on the new roof with every attachment flashed into the shingle courses.
- Put an Enphase IQ8M microinverter under each module, landing in an IQ Combiner beside the unit's service.
- Filed an interconnection application that was reviewed, confirmed and site-assessed on the day it was submitted.
- Carried the project to permission to operate fourteen days after filing.
System specifications
| System | 2.28 kW AC-CEC |
|---|---|
| Dwelling | New detached ADU, 29 × 37 ft, certificate of occupancy issued |
| Modules | Mission Solar |
| Inverters | Enphase IQ8M, one per module |
| Combiner | Enphase IQ Combiner 4 |
| Roof | Composition shingle, new |
| Battery | None |
| Application to PTO | Fourteen days |
| Utility / AHJ | LADWP / LADBS |
Is your project like this one?
- You have built an accessory dwelling unit and want solar on it.
- You want to know why a small system can move faster than a large one.
- You are planning an ADU and want to know when the solar conversation starts.
- You have been told any interconnection takes months.
- Your West Hills property is served by LADWP, while permits are handled by LADBS.
Cali Energy in West Hills
West Hills is inside City of Los Angeles boundaries: permits run through LADBS, interconnection through LADWP.
Lots here are deep enough to take a detached second dwelling without crowding the house, and a detached unit means its own service and its own interconnection.
This installation is on the West Hills projects page alongside the others, and what the work covers is set out on the West Hills service area page.
- License and classifications: CSLB #1032379
- Official reference for this process: Los Angeles City Planning — housing policies and ADUs
- Official reference for this process: LADWP interconnection requirements
Frequently asked questions
Can an ADU have its own solar system?
If it has its own meter, yes — and then the array is its own interconnection, on its own work request, sized to that meter. This unit is a new detached dwelling of twenty-nine by thirty-seven feet with a certificate of occupancy, and the solar on it is separate from anything else on the lot.
How fast was this one?
Fourteen days. The application was filed on the thirtieth of November 2023, the utility reviewed and confirmed it and closed the site assessment the same day, and permission to operate came on the fourteenth of December. That is this project's record, not a schedule we can promise on another one: the utility's route through a request also depends on whether the service has to be upgraded and on what else sits behind the meter.
Is 2.28 kilowatts worth doing?
On this unit it was the size that fitted the roof plane and the meter it connects to. What size is right for a given accessory dwelling unit depends on that unit's own consumption and its own service, which is worth working out before the array is designed.
Does the ADU need to be finished before the solar can be connected?
In practice yes. The utility connects generation behind a live service, so the building has to exist and be occupiable first. That is why the building permit and the certificate of occupancy sit ahead of the interconnection in the calendar.
Does Cali Energy do ADU solar in West Hills?
Yes. Cali Energy holds B, C-10 and C-39 classifications under CSLB #1032379, which covers the roof, the electrical and the array. West Hills is inside City of Los Angeles boundaries, so permits run through LADBS and interconnection through LADWP.
What this would look like on your roof
Every number on this page came off a real job in West Hills, CA — not a brochure. Tell us your utility, your roof and what your bill looks like now, and we will model your own version of it before you commit to anything.
Or call +1 (323) 844-7777 · Cali Energy, Northridge · CSLB #1032379 (B, C-10, C-39) — design, permits, install and electrical under one licensed contractor.
Related
This timeline reflects this property and this permitting path. Updated September 2026.