Glassell Park, CA · August – November 2022 · LADWP / LADBS

Glassell Park: sized to the bill, not the roof.

The first design filled the roof and would have produced nearly twice what the house uses. The system that got built was half of it.

A residential solar system in Los Angeles is sized against the household's own annual consumption, not against how many modules the roof will hold. Production beyond what a house uses is credited at a lower value than the electricity it offsets, so an oversized array costs more and returns less per panel. On this Glassell Park project Cali Energy revised a twenty-six module, 10.4 kW design down to fourteen modules and 5.6 kW AC-CEC after the annual usage came in under 9,000 kWh, and the system reached permission to operate thirty days after filing.

All-black solar modules on a composition shingle roof above a flat parapet, with trees and hillside behind, Glassell Park, Los Angeles
Fourteen modules, where twenty-six had been drawn.

At a glance

System as built
5.6 kW AC-CEC
Array
14 modules, 400 W each
Inverters
One microinverter per module
First design
26 modules, 10.4 kW
Household usage
Under 9,000 kWh a year
Filing to permission to operate
Thirty days

The story

The first design for this hillside house was twenty-six modules at four hundred watts, one microinverter behind each, ten and a half kilowatts, with an estimated annual production near sixteen thousand kilowatt-hours. It fitted the roof and it would have been a good-looking installation.

Then the consumption came back. The household was using under nine thousand kilowatt-hours a year.

A solar array on a small pitched roof section seen across a flat roof deck, with a hillside beyond, Glassell Park, Los Angeles
The southwest face, at a five degree tilt.

The design was cut to fourteen modules on the southwest face, at a five degree tilt, with an estimated production of about eight thousand seven hundred. Five point six kilowatts instead of ten and a half. Slightly more than half the array, sold at slightly more than half the price.

This is the part of a solar quote worth understanding, because the incentive runs the other way and everybody knows it.

The same all-black array from the opposite corner of the roof deck, Glassell Park, Los Angeles
5.6 kW against a household using under 9,000 kWh a year.

Under net metering the electricity a system makes is worth the most when the house consumes it directly — it offsets power you would otherwise buy, at the full retail rate you would have paid. Production beyond what the house uses is exported, and export is credited at a lower value than the retail rate. That means every panel past the point where annual production matches annual consumption earns less than the panels before it, while costing the same to buy and install.

So the right first question is not how much roof there is. It is how many kilowatt-hours a year the house actually uses, and that number is on the bill. A proposal that has not been built against it is a proposal about a roof, not about a household.

There are legitimate reasons to size above current consumption, and they are worth naming so this does not read as a rule against big systems. A vehicle about to be charged at home. An air conditioner or heat pump going in. A household that is about to grow. What those have in common is that they are future load somebody has actually decided on — not a roof that happened to have space.

None of them applied here, so the array came down to size.

The rest ran quickly. The agreement was signed in the middle of September and the drawings were approved on the tenth of October. The interconnection request was confirmed the following day at 5.6 kW AC-CEC, with the first, second and fourth progress notices all recorded together — the acknowledgement, the confirmation of details, and the site assessment completed or waived. The utility charge cleared the next morning.

The installation was approved on the thirty-first of October and permission to operate came on the tenth of November. Thirty days from filing.

One thing to take away if you are holding two quotes. Ask each of them what your annual consumption is and where they got the figure. If one of them cannot tell you, the system it is proposing was sized by something other than your electricity use.

A junction box and metal conduit running along a stucco parapet wall below a solar array, Glassell Park, Los Angeles
Thirty days from filing to permission to operate.

Cali Energy designed, permitted and interconnected this 5.6 kW array in Glassell Park, Los Angeles.

How it ran

18 August 2022Site inspection arranged
23 August 2022First design — 26 modules, 10.4 kW, estimated 15,900 kWh a year
24 August 2022Annual consumption comes in under 9,000 kWh; design revised to 14 modules on the southwest face at five degrees, about 8,700 kWh a year
16 September 2022Agreement signed
10 October 2022Drawings approved
11 October 2022Interconnection request confirmed — 5.6 kW AC-CEC; first, second and fourth progress notices recorded together
12 October 2022Utility charge processed
31 October 2022Installation approved
10 November 2022Permission to operate

Thirty days from filing to permission to operate. The decision that shaped the project was taken eleven weeks earlier, off a consumption figure.

What we did

  • Checked the household's annual consumption before finalizing the design.
  • Cut the array from twenty-six modules to fourteen rather than filling the roof.
  • Concentrated the smaller array on the southwest face at a five degree tilt.
  • Filed the interconnection request the day after the drawings were approved.
  • Closed filing to permission to operate in thirty days.

System specifications

System5.6 kW AC-CEC
Modules14 × 400 W, all black
InvertersOne microinverter per module
OrientationSouthwest face, five degree tilt
Design revised from26 modules at 10.4 kW
Sized againstAnnual household consumption under 9,000 kWh
Utility / AHJLADWP / LADBS

Is your project like this one?

  • You have a solar quote and nobody has mentioned your annual kilowatt-hours.
  • Two proposals for your house differ by half the panel count.
  • You want to know how big a system your house should actually have.
  • You are weighing whether to size up for an electric vehicle or a heat pump.

Cali Energy in Glassell Park

Glassell Park is a hillside neighborhood in northeast Los Angeles, inside city boundaries and therefore permitted through LADBS and interconnected through LADWP. The lots are small and the roofs are broken by slope, so the question of how much array a house should carry comes up earlier here than elsewhere.

This installation is on the Los Angeles projects page alongside the others, and what the work covers is set out on the Los Angeles service area page.

Frequently asked questions

How big should my solar system be?

Sized against your annual kilowatt-hour consumption rather than against how many modules fit the roof. Under net metering, production the house consumes directly offsets power at the full retail rate, while production beyond that is exported and credited at a lower value. Panels past the match point cost the same and earn less than the ones before them.

Why would a solar company propose a smaller system?

Because the household's usage did not justify the larger one. On this Glassell Park project the first design was twenty-six modules at 10.4 kW with an estimated 15,900 kWh a year; the annual consumption came in under 9,000 kWh, so the array was cut to fourteen modules and 5.6 kW. The smaller system matches what the house actually uses.

When does it make sense to size above current consumption?

When there is future load somebody has actually decided on — an electric vehicle to be charged at home, an air conditioner or heat pump going in, a household about to grow. Those are reasons to build headroom. A roof that happens to have space left on it is not one, because the extra panels earn export credit rather than retail offset.

What should I ask a solar company about my quote?

Ask what your annual consumption is and where the figure came from. It is on your electricity bill, and the system size should be built from it. If a company proposing a system cannot tell you that number, the design was sized by something other than your electricity use — usually the available roof area.

Does Cali Energy install solar in Glassell Park, Los Angeles?

Yes. Glassell Park is inside city limits, so projects here are permitted through LADBS and interconnected through LADWP. The hillside lots break the roof into small faces, which makes the choice of which face to use — and how much array to put on it — a larger part of the design than on flatter ground.

What this would look like on your roof

Every number above came off a real job in Glassell Park, 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.