California interconnection applications
61 electric utilities serve California (EIA-861, 2025): 6 investor-owned utilitys, 33 municipal utilitys, 13 public power districts, 4 electric cooperatives, 4 federal power agencys, 1 community choice aggregator (no grid). Together they serve 14,207,431 residential customers; 2,241,381 residential customers were on net metering at year-end 2025.
Largest utilities in California
Investor-owned utility · 5,055,556 residential customers · California
Applications: Own online portal – PG&E Interconnection Portal (YourProjects)
Interconnection process and documents →Investor-owned utility · 4,627,247 residential customers · California
Applications: PowerClerk – SCE Interconnection Online Application System
Interconnection process and documents →Municipal utility · 1,415,602 residential customers · California
Applications: Own online portal – LADWP NEM Portal (online interconnection application; issues Work Request number WR#)
Interconnection process and documents →Investor-owned utility · 1,378,465 residential customers · California
Applications: Own online portal – Distribution Interconnection Information System (DIIS)
Interconnection process and documents →Public power district · 601,275 residential customers · California
Applications: PowerClerk – SMUD Interconnection (PowerClerk)
Interconnection process and documents →Public power district · 142,916 residential customers · California
Applications: PowerClerk – IID Rooftop Solar PowerClerk (customer or contractor account)
Interconnection process and documents →Municipal utility · 107,148 residential customers · California
Interconnection process and documents →Public power district · 104,671 residential customers · California
Interconnection process and documents →Municipal utility · 101,042 residential customers · California
Interconnection process and documents →Public power district · 80,976 residential customers · California
Interconnection process and documents →Municipal utility · 78,071 residential customers · California
Applications: PowerClerk
Interconnection process and documents →Municipal utility · 64,556 residential customers · California
Interconnection process and documents →Export compensation among the researched California utilities: Net billing, NEM. Rules differ by utility – see each utility page.
California interconnection rule
Rule 21 tariff PDFs not read in full (PG&E file too large, SDG&E host unreachable): insurance, disconnect, NEM/NBT fee and document list unverified; documents list is typical, confirm in tariff Section E. NBT cap 1 MW per PU Code 2827 eligibility - confirm.
California Public Utilities Commission (CPUC)
Interconnection ruleCPUC Electric Tariff Rule 21 (utility-filed, CPUC-approved); D.20-09-035 timelines; current rulemaking R.25-08-004 – Rule 21 - Generating Facility Interconnections · source
Applies toCPUC-jurisdictional IOUs: PG&E, SCE, SDG&E, Bear Valley Electric, Liberty Utilities (CalPeco); PacifiCorp uses OATT-based process under D.07-07-027. Not munis/POUs (LADWP, SMUD, IID etc.). Wholesale-market facilities go under WDT/CAISO.
Application formUtility-specific Rule 21 interconnection request forms filed with CPUC (e.g. SCE Form 14-957 for NEM/NBT, 14-732 non-export); submitted via each IOU's online portal.
TimelinesInitial Review 15 BD; Supplemental Review 20 BD; draft interconnection agreement or cost estimate within 15 BD after review; D.20-09-035 requires tracking of 19 timelines and standard construction/meter timelines.
Fees$800 interconnection request fee; $2,500 supplemental review (SCE page). NEM-2/NBT <=1 MW historically exempt from study costs; NEM/NBT request fee amount is utility-specific (not verified here).
Export compensationNet billing – Pub. Util. Code §2827.1; CPUC D.22-12-056 (Net Billing Tariff, 'Solar Billing Plan'); Res. E-5301
NBT applies to IOU applications submitted on/after 2023-04-15; exports credited at avoided-cost-based values; required TOU rates (E-ELEC, TOU-D-PRIME, EV-TOU-5); 9-year legacy. Earlier NEM 1.0/2.0 grandfathered.
Publicly owned utilities are not under Rule 21 and set their own interconnection rules; PU Code §2827 net metering obligations applied to POUs until their 5% cap; POUs now offer own successor tariffs.
| Level | Up to | Criteria / review / fee |
|---|---|---|
| Fast Track - Initial Review | Screens; NEM/NBT and non-exporting projects eligible for Fast Track regardless of nameplate (per SCE) · 15 business days after application deemed complete · $800 interconnection request fee (non-NEM); NEM/NBT fee per utility tariff | |
| Fast Track - Supplemental Review | If Initial Review screens fail · 20 business days after fee received · $2,500 | |
| Detailed Study (Independent / Distribution Group / Transmission Cluster) | Projects failing Fast Track · Independent Study Screen Q/R results within 20 BD of deposit; Distribution Group 30 BD after window · Study deposit per Rule 21 Table E.1 |
- CPUC Rule 21 Interconnection: https://www.cpuc.ca.gov/Rule21/ (retrieved 2026-11-13)
- CPUC Net Energy Metering and Net Billing: https://www.cpuc.ca.gov/industries-and-topics/electrical-energy/demand-side-management/customer-generation/net-energy-metering-and-net-billing (retrieved 2026-11-13)
- SCE Interconnecting Generation under Rule 21: https://www.sce.com/business/smart-energy-solar/solar-for-business/grid-interconnections/interconnecting-generation-under-rule-21 (retrieved 2026-11-13)
All 61 utilities in California
- PG&E5,055,556
- SCE4,627,247
- LADWP1,415,602
- SDG&E1,378,465
- SMUD601,275
- IID142,916
- City of Anaheim107,148
- Modesto Irrigation District104,671
- City of Riverside101,042
- Turlock Irrigation District80,976
- City of Glendale78,071
- City of Roseville64,556
- City of Pasadena58,602
- City of Santa Clara54,000
- City of Burbank Water and Power46,719
- Liberty (CalPeco, Lake Tahoe CA)44,507
- City of Redding39,152
- Rocky Mountain Power (UT, ID, WY) / Pacific Power (OR, WA, CA)36,339
- Alameda Municipal Power32,364
- City of Palo Alto25,672
- City of Lodi24,215
- Bear Valley Electric Service (BVES)23,395
- City of Colton17,367
- City of Azusa15,646
- Merced Irrigation District11,850
- City of Moreno Valley7,952
- City of Shasta Lake4,278
- City & County of San Francisco3,670
- Surprise Valley Electrification2,788
- City of Corona1,305
- City of Vernon73
- Valley Electric Association, Inc.12
- City of Lompoc0
- Truckee Donner P U D0
- City of Banning0
- Lassen Municipal Utility District0
- Plumas-Sierra Rural Electric Cooperative0
- City of Ukiah0
- Trinity Public Utilities District0
- City of Healdsburg0
- Anza Electric Cooperative Inc.0
- Lathrop Irrigation District0
- Rancho Cucamonga Municipal Utility0
- Colorado River Indian Irr Proj0
- City of Gridley0
- City of Needles0
- DOD USMC Marine Air Ground Combat0
- Aha Macav Power Service0
- Kirkwood Meadows PUD0
- City of Biggs0
- Shelter Cove Resort Improvement District No. 10
- Pittsburg Power Company0
- WAPA-- Western Area Power Administration0
- Port of Oakland0
- City of Victorville0
- Port of Stockton0
- Tuolumne County Public Power Agny0
- Bonneville Power Administration0
- City of Escondido0
- Kings River Conservation District0
- Central Coast Community Energy0
Residential customers in California per EIA-861 (2025). Customer counts = bundled + delivery-only service (EIA-861 Part A + Part D). Service territory is reported by county; a county can be served by several utilities.
$500 / month
Unlimited interconnection applications. 12-month agreement, signed online. The agreement starts the day you sign; first invoice right away, then monthly.
- Unlimited interconnection applications
- Single-line diagram and site plan for every application
- Pre-submission check against the utility’s requirements
- Homeowner e-signature link for the authorization
- Filing in your utility portal accounts or by the utility’s method
- Utility questions, corrections and resubmissions
- Follow-up through approval, inspection and PTO
- Customer list, exports, API and webhooks
Applications are typically submitted within 2 business days after complete documents. Utility review times are set by each utility.