Clean Coalition sees interconnection wins in Rule 21 Proposed Decision - Clean Coalition
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Clean Coalition sees interconnection wins in Rule 21 Proposed Decision

The PD includes a number of Clean Coalition recommendations that will streamline the deployment of large quantities of local renewables.

Sahm White


The California Public Utilities Commission (CPUC) recently issued a Proposed Decision (PD) on Rule 21, which regulates interconnection, operation and metering requirements for distributed generators.

The PD includes a number of Clean Coalition recommendations that will streamline the deployment of large quantities of local renewables. Importantly, California’s Rule 21 is widely used by other states as a foundation for their interconnection rules, so our precedent-setting work will accelerate the transition to clean local energy nationwide.

The CPUC’s PD calls for a Distribution Group Study Procedure (DGSP) – closely following Clean Coalition recommendations – to establish group interconnection studies for related distributed generation projects in the same area every six months. Previously, related interconnection studies were performed sequentially, which frequently resulted in long and unpredictable delays.

Importantly, the DGSP ensures that related projects proportionally share upgrade costs. This will avoid project cancelations from large – and potentially inequitable – individual cost assignment as existing equipment thresholds are reached.

The Clean Coalition also successfully petitioned the CPUC to require new quarterly reports from investor owned utilities. These reports will allow the CPUC to track the utilities compliance with interconnection timelines and give regulators and developers a better sense of how all projects are progressing. In order to maximize transparency about cost predictability and the potential to standardize costs, the PD empowers the CPUC Energy Division to ask utilities for additional information beyond what was specified in the ruling.

Lastly, the PD formally adopts the Clean Coalition’s Rule 21 initiative for pre-application reports, which gives applicants an opportunity to better evaluate the suitability of a site, identify known interconnection issues, and optimize their facility size to minimize grid upgrade costs. Pre-application reports are available for a flat fee of $300 per report.

The Clean Coalition successfully motioned the Federal Regulatory Energy Commission to also require the pre-application option in the national Small Generator Interconnection Procedures.

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.