Improving interconnection cost certainty under Rule 21‬‬‬‬‬‬ - Clean Coalition
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Improving interconnection cost certainty under Rule 21‬‬‬‬‬‬

The Proposed Decision from the Joint Motions filed in the proceeding enhances cost predictability, access to information, and standards for energy storage.

Sahm White


The Clean Coalition continuesdrivingimprovements to the California Public Utilities Commission’s (CPUC) Rule 21, which regulates interconnection, operation, and metering requirements for distributed generation in California. We are pleased to report that the past few months have proved fruitful with agreement achieved among parties on multiple proposals by the Clean Coalition and others.

The Proposed Decision (PD) from the Joint Motions filed in the proceeding enhances cost predictability, access to information, and standards for energy storage. We look forward to their implementation once the commissioners at the CPUC adopt a Final Decision.

As previously reported, late last year the Clean Coalition led a series of proposals for joint parties to submit to the CPUC. As reflected in the current PD, the following recommendations went unopposed:

  • The publication of an interconnection “Per Unit Cost Guide,” which will guide applicants through the interconnection process with assured cost certainty and transparency.
  • The implementation of further enhancements to the pre-application report the Clean Coalition had previously succeeded in establishing.
  • The streamlining of interconnection processes of non-exporting energy storage and treatment of storage-related loads.

Options offering cost certainty in interconnection agreements are also going before the CPUC for a final decision. These options offer contractual cost certainty to address current non-binding estimates from utility companies that leave interconnection applicants with unbounded liability for costs incurred during project development. This is an issue the Clean Coalition has pursued since the Rule 21 proceeding began in 2011,and while no further consensus was achievable regarding alternative approaches, wewill continue advocating for neededimprovements.

The CPUC recognizes that more work needs to be done on the cost certainty proposals, such as incorporating the smart inverter recommendations in Rule 21 and issuing a new rulemaking to address additional issues that will arise or are still outstanding.

As a leading intervener on Rule 21, the Clean Coalition has already achieved a number of important victories, and we will continue fighting for fair, transparent, and streamlined interconnection processes.

Sahm White

Economics and Policy Analysis Director

Sahm has over 20 years of experience in economic and environmental policy, with over 200 filings before public utility and energy commissions. Prior to joining the Clean Coalition, he held positions as a Senior Research Consultant to the Center for Ecoliteracy, Technical and Policy Analyst in the development of the Ecological Footprint, and Associate Director of Progressive Secretary, a leading web source of legislative constituent engagement.