Electric Rule 21 is a tariff that describes the interconnection, operating and metering requirements for generation facilities to be connected to a utility’s distribution system, over which the California Public Utilities Commission (CPUC) has jurisdiction. The Rule 21 tariff for each of California’s large investor owned utilities (IOUs) is available on each IOU’s website. Note that the posted Rule 21 may not reflect updates to the tariff that may be pending before the CPUC:
The CPUC's open interconnection proceeding is R.11-09-011. For information or to discuss a matter related to distribution system interconnection, contact Jamie Ormond, Energy Division, at Jamie.Ormond@cpuc.ca.gov or 415-703-1193.
May 13, 2014: Assigned Commissioner’s Amended Scoping Memo and Ruling
Rule 21 Interconnection - Quarterly Report for Q1 2014 - Public Version
Smart Inverter Working Group Recommendations for Rule 21 Updates:
Recommendations for Updating the Technical Requirements for Inverters in Distributed Energy Resources
Interconnection & Energy Storage Meeting
10:00am – 2:30 pm
Phone in: 1-866-758-1675
Pass Code: 7646128#
Please note that the Rule 21 website is under construction and will be updated shortly.
September 25, 2012: Assigned Commission Phase II Scoping Memo Issued
Assigned Commissioner Michel P. Florio issued a Phase II Scoping Memo in R,11-09-011, setting out the high-priority issues to achieve the Commission's goal of ensuring a timely, non-discriminatory, cost-effective, and transparent process for interconnection to the utility distribution system.
September 13, 2012: Rule 21 Settlement Approved
In Decision 12-09-018 the Commission approved the full set of reforms to Rule 21 proposed via a multi-party settlement. The Commission anticipates that the significant reforms achieved in Rule 21 will advance the Commission's goals of ensuring a timely, non-discriminatory, cost-effective, and transparent interconnection process for distributed generation in California.
March 16, 2012: Rule 21 Settlement filed
On March 16, 2012, fourteen parties to the Distribtuion System Interconnection Settlement Process filed a settlement in CPUC Rulemaking (R.)11-09-011.
The settling parties are: Aloha Systems, California Farm Bureau Federation, Center for Energy Efficiency and Renewable Technologies, Clean Coalition, Interstate Renewable Energy Council, Pacifc Gas and Electric Company, San Diego Gas & Electric Company, Sierra Club, solar Energy Industries Association, Southern California Edison, SunEdison, Sunlight Partners, Sustainable Conservation, and Vote Solar Initiative.
The centerpiece of the settlement is significantly reformed CPUC-jursidictional Rule 21 interconnection tariff. Upon launching the settlement process for Rule 21 in August 2011, the CPUC's goal was to craft transparent rules that provide a clear, predictable path to interconnection for distributed generation while maintaining the safety and reliability of the electric grid.
See here for the full Motion for Approval of Settlement Agreement Revising Distribution Level Interconnection Rules and Regulations.
September 22, 2011: CPUC approves Distribution Interconnection Proceeding
The CPUC approved an OIR (R.11-09-011) to “review the rules and regulations governing interconnecting generation and storage resources to the electric distribution systems of Pacific Gas and Electric Company (PG&E), Southern California Edison Company (SCE), and San Diego Gas & Electric Company (SDG&E).” The OIR is the procedural forum for the Distribution System Interconnection Settlement Process.
August 23, 2011: Distribution System Interconnection Settlement Process
The CPUC launched a multi-party Distribution System Interconnection Settlement Process intended to reach a global settlement on issues regarding distributed generation interconnection to the investor-owned utility distribution system in California. The Settlement Process is subject to confidentiality rules, pursuant to CPUC Rule 12, and FERC Rule 602.
Rule 21 Working Group
The Rule 21 Working Group has served since 2000 as the source of ideas for maintaining and updating technical and other standards within the Rule 21 tariff. The Rule 21 Working Group is not meeting in its usual format while the Distribution System Interconnection Settlement Process is underway. Future public meetings of the Rule 21 Working Group will be noticed in the Commission’s Daily Calendar.
August 2011 Working Group Workshops
- August 19, 2011, 9:00 a.m.-12:00 p.m., CPUC Auditorium: Rule 21 Working Group Workshop. Off-site participation: This workshop will be available via video webcast in real-time and archived. Presentation available here.
- August 19, 2011, 1:00-4:00 p.m., CPUC Courtyard Room: Rule 21 Working Group Technical Subcommittee Meeting. Offsite participation will be available by phone. Phone-in information will be sent only to participants who have completed an rsvp form at the link below. Presentation available here.
- August 23, 2011, 1:00-4:00 p.m., CPUC Courtyard Room: Rule 21 Working Group Business Practices Subcommittee Meeting. Offsite participation will be available by phone. Phone-in information will be sent only to participants who have completed an rsvp form at the link below. Presentation available here.
Download the full agenda for the above meetings
April 2011 Working Group Workshops
CPUC held a Rule 21 Working Group Workshop Friday, April 29, 2011 at the CPUC Auditorium.
Download a printable agenda here
Workshop presentation materials:
About the Rule 21 Working Group
The intent of the Rule 21 Working Group is to build consensus among the CPUC, IOUs, generators, and advocates for Rule 21 reforms to meet the technical needs and policy goals of interconnecting distributed generation. The Rule 21 Working Group succeeded at this goal in its past work, making California's Rule 21 a national model tariff establishing metering and operating standards for interconnecting distributed generation resources. Following three years of extensive change in the statutory, technological, and generator context, however, Rule 21 is widely agreed to be in need of reconsideration.
The purpose of this kickoff meeting is to initiate discussion of the issues emerging under Rule 21 that may be hindering the achievement of California's distributed generation goals. Below are examples of such issues that CPUC has identified:
- Need for transparency in terms of processing, queue information, and customer application information;
- Need for review and potential reconsideration of technical screens within Rule 21 to ensure that the appropriate issues are being studied;
- Need for articulation of cost allocation methodology where network upgrades are required;
- Need for review of utility tariff consistency with each other and with state law;
- Need for additional standard interconnection agreements to accommodate the different types of distributed generation projects anticipated to come online.
June 20 2008: Workshop on Rule 21
On June 20, 2008, the California Public Utilities Commission (CPUC) held a workshop on the topic of the Rule 21 interconnection standard. The primary focus of the workshop was to discuss the transition of Rule 21 oversight from the California Energy Commission (CEC) to the CPUC.
A more detailed history of the Rule 21 Working Group is available on the CEC website. For more information about past Rule 21 Working Group activities visit http://rule21.ca.gov/.