New IREC Research on an Emerging Clean Energy Interconnection Tool

The Interstate Renewable Energy Council today released a report that provides guidance on the use of “group studies,” an emerging practice to streamline the interconnection of distributed energy resources (DERs) — such as solar PV, community solar, and energy storage — to the electric distribution grid.

The report, Thinking Outside the Lines: Group Studies in the Distribution Interconnection Process, aims to help regulators, utilities, and clean energy stakeholders evaluate whether group studies may be an effective avenue for addressing interconnection issues in their jurisdictions. This is an important and timely question because, as an increasing number of DER projects seek to interconnect to the grid, the interconnection process has slowed in many states. It is not uncommon for DER projects to spend years waiting in a queue to be studied.

“Interest in group studies at the distribution level has been growing, and this paper investigates how these studies are faring on the ground,” said Laura Beaton of Shute, Mihaly and Weinberger LLP, counsel for IREC and the lead author of the paper. “One of our major takeaways from our research is that group studies are not a silver bullet for all interconnection challenges, but they can frequently be helpful in managing queues and fairly allocating costs.”

The  standard practice over the last 20 years has been to study DER projects one at a time, in the order in which they requested to interconnect, to determine if each can safely interconnect to the distribution system and if any grid upgrades will be needed. This process of studying projects one-by-one can contribute to projects piling up in the queue as they await their turn to be studied. In contrast, a “group study” evaluates in a single study whether a group of multiple electrically related DER projects can safely interconnect and identifies any grid upgrades that are needed to accommodate the group. Unlike individual studies, projects in the same group typically share the costs of the study and any common distribution or network upgrades. While common at the transmission level, group studies have only recently been widely considered at the distribution level.