Where is residential solar demand now?

Steps

1. Filtered to Service County = Los Angeles (matched without regard to capitalisation; one in-window row is spelled LOS ANGELES), Customer Sector = Residential, within SCE's service territory.
2. Kept only genuine install/expansion application statuses (Interconnected and Expansion-*), dropping administrative-only records like corrections, duplicates, and withdrawals.
3. Cast date, system size, storage, and cost fields to proper types; parsed 'Storage Capacity (kWh)' into a has_storage flag.
4. Cleared Cost/Watt values outside a plausible $0.10-$50/W range (a small number of data-entry outliers) rather than trying to guess a corrected value.
5. Checked whether Cost/Watt bundles storage cost: storage-attached systems show notably higher Total System Cost for only modestly larger system_size_kw, so storage cost is bundled in. Median cost/watt is therefore reported separately for PV-only and storage-attached systems rather than as one mixed pre/post NBT number.
6. Grouped installers outside the top 10 by 12-month volume into an 'Other installers' category for the market-share chart.
7. Published only summary tables (counts, sums and a few precomputed medians), not applications. The 12 largest cities are named; every other city, and any city or installer cell with fewer than 10 applications, is combined into an 'All other' row so totals still add up. Row-level data is not republished because of the publisher's Terms of Use; the figures were computed from the publisher's file.

416,755 applications in the publisher's file, 102,529 in scope, published as 1,125 summary rows. Every derived figure on this page (changes, indexes, averages, counts) is computed from the published rows, and the table under each chart says how.

Checks

• 17 checks passed against the publisher's published summaries; a statewide file (PG&E, SCE, SDG&E) was used only for cross-checks.
• Cost per watt is reported separately for PV-only and storage systems, because storage cost is bundled into the total.
• Each table on this page is the published chart data in solar.json, shown row for row.

Caveats

• Covers only Southern California Edison territory; the City of Los Angeles (LADWP) and other municipal utilities (Burbank, Glendale, Pasadena) are not included, so this is LA County within SCE's service area, not the whole county. The source file is the publisher's 5-year SCE-only export (approved dates from September 2021 onward), not the full multi-utility statewide history. The file leaves out applications still pending, so received counts for the latest months are low. Only summary tables are published: the publisher's Terms of Use restrict extracting or distributing its content, so row-level data is not republished and every figure was computed from the publisher's file. In the city and installer breakdowns, any cell with fewer than 10 applications is combined into an 'All other' row; the tariff and period table has no place or installer, so its small cells are kept.

Releases and revisions

• As of Aug 31, 2026. Pending applications are not in the file, so recent received counts rise as they are approved.