Regulatory Information - Open Access

Open Access Information

Transmission Owner Tariff - effective June 1, 2010

Wholesale Distribution Access Tariff (WDAT) Combined - effective May 28, 2010

Rule 21 Tariff - effective July 9, 2014

Overview of Generation Interconnection Process

Generation of energy requires a physical interconnection between the generator and the existing SCE Transmission/Distribution Grid. SCE will need to study your project and prepare an Interconnection Agreement between SCE and the generator. For projects at lower voltage levels (typically 66kV or less), the Wholesale Distribution Access Tariff will apply. Regardless, your first step is to submit a WDAT Application with technical data and a Distribution Service Application to SCE.

If your project is interconnecting at higher voltage (typically anything higher than 66kV), there is a similar, but distinct, process that is led by the California Independent System Operator who coordinates with SCE for projects in our region. Information for that process can be found in the CAISO's Tariff.

To sell your generation, or net it against your existing usage (net metering), you'll need to work with other groups at SCE or other agencies that wish to buy power. For net metering and related programs, click here. For power sales to SCE, click here for SCE Power Purchase Programs and the best Power Purchase Agreement for your project.

Cluster Application Window Schedule

Applicable to Generator Interconnection Requests Processed Under the Cluster Study Process

In accordance with SCE's WDAT Generator Interconnection Procedures (GIP), Cluster Application Windows will be opening (and closing) within the following schedule:

Anticipated Queue Schedule
Cluster Opening Date Closing Date
Queue Cluster 9 Application Window Fri Apr 01, 2016 Mon May 2, 2016

Interconnection Requests for processing under a Cluster Process must be submitted during a Cluster Application Window.

Rule 21 Distribution Group Study Application Window

In accordance with SCE's Rule 21 generator interconnection procedures, SCE will open a Distribution Group Study (DGS) Application Window within the following schedule:

DGS Application Window Schedule
Cluster Opening Date Closing Date
DGS Cluster 3 Tue Sep 1, 2015 Wed Sep 30, 2015

Interconnection Requests to be studied under the Distribution Group Study Process shall either be (a) an Independent Study Process Interconnection Request that passed screen Q and failed Screen R for which the Applicant elects to continue to the next available Distribution Group Study, or (b) an Interconnection Request submitted during a Distribution Group Study Application window that passes Screen Q. Please refer to Rule 21 for a description of Screens R and Q Rule 21 Link.

New Interconnection Requests for the Independent Study Process will NOT be accepted during the Distribution Group Study application window dates listed above.

Notice of CAISO's Distributed Generation Deliverability Assignment Application Window

The California Independent System Operator (CAISO) opened the 2015 window for the distributed generation deliverability (DGD) allocation process pursuant to CAISO Tariff Section The CAISO is working with utility distribution companies assigning deliverability status to eligible distributed generation facilities

Distributed Generation Deliverability (DGD) Overview

The CAISO established DGD annual allocation process to enable distributed generation resources (DG Facilities) that are interconnecting to the utility distribution grid to obtain Partial or Full Capacity Deliverability Status by allocating “Potential DGD” (as identified by the CAISO in their annual DGD Assessment Results to eligible DG Facilities. For more information about the DGD Allocation process, please refer to the CAISO’s Business Practice Manual for Distributed Generation Deliverability located at:

The CAISO has posted the distributed generation deliverability assessment results to its website at

Application Instructions for Facilities in SCE's Service Territory

Owners of distributed generation facilities interconnected or seeking interconnection to Southern California Edison's distribution system (under SCE’s Wholesale Distribution Access Tariff or Rule 21) who are interested in participating in CAISO's Distributed Generation Deliverability allocation process can submit an application as shown below. The application must be received by 5:00 p.m. (Pacific Time) Friday, April 17, 2014. You can email electronic signed copies of the application to


Eligibility Worksheet

Before beginning the application, please use the attached Eligibility Worksheet to evaluate the project’s eligibility to apply for the Distributed Generation Deliverability allocation process. However, in the case of discrepancies, CAISO’s tariffs and applicable interconnection process prevail.


SCE’s DGD - Prior Year Results

SCE’s DGD – Current Year Results

Additional Information

Questions regarding this application or the deliverability assignment process can be sent to


Rule 21 Ombudsman Information

To address disputes regarding Rule 21 missed timelines, please contact SCE's appointed ombudsman

Rod Vickers, Project Manager
Ph: (714) 895-0211

Public WDAT-Rule 21 Queue

SCE- WDAT and Rule 21 Interconnection Requests (Excel)

Financial Security Forms

Contact Us

Should you have any questions regarding SCE's Open Access Information, please contact us via one of the following methods:

Phone: (626) 302-3688
Mailing Address:

Grid Interconnection & Contract Development
Southern California Edison
2244 Walnut Grove Ave
PO Box 945
Rosemead, CA 91770