Early evidence from FERC's landmark interconnection overhaul shows measurable progress for grid-scale battery storage developers. Interconnection agreements reached a record high in 2024, and total queue volume declined for the first time in at least a decade. The reforms, introduced under Order No. 2023 in July 2023, are beginning to move viable projects toward construction, though regional implementation remains uneven and analysts caution the full impact has yet to be felt.
Background
On July 28, 2023, FERC issued Order No. 2023, the most significant overhaul of generator interconnection procedures in decades, aimed at reducing backlogs, improving process certainty, and ensuring grid access for new technologies including battery storage. The rule replaced the longstanding first-come, first-served serial review model with a cluster-based, first-ready, first-served study process. It also introduced higher financial readiness deposits, mandatory site control requirements, and financial penalties for grid operators that miss study deadlines.
The urgency was clear from queue data. As of the end of 2023, approximately 2.6 terawatts of generation and storage capacity were stuck in interconnection queues nationally-more than 1.5 times the entire installed U.S. electrical capacity at the time. Solar and battery storage projects made up the bulk of that backlog.
Transmission providers were required to submit compliance filings by May 2024. According to legal analysis published by Balch & Bingham in November 2025, while some compliance filings have been accepted and others remain pending, "the essential elements of most interconnection processes are settled"-meaning the framework is now broadly operational across most jurisdictions.
Details
The first measurable sign of progress came through interconnection agreements. In 2024, U.S. grid interconnection agreements jumped 33% to a record 75 GW, a surge credited largely to FERC Order 2023 reforms that reduced speculative projects and cleared queue backlogs, according to consulting group Wood Mackenzie. Solar and battery storage projects accounted for approximately 75%, or 58 GW, of all agreements signed in 2024, and Wood Mackenzie projected a similar market share for 2025.
Total interconnection queue capacity fell from 2,600 GW in 2023 to 2,300 GW in 2024-the first decline in at least a decade-according to data published by the Solar and Storage Industries Institute (SI2). Grid-scale battery storage saw a record 11 GW of previously backlogged capacity come online in 2024, alongside 31 GW of large-scale solar, contributing to the queue reduction.
Wood Mackenzie analyst Kaitlin Fung stated the reforms are showing "early signs of promise in accelerating the pace of interconnection studies." However, SI2 cautioned that most projects reflected in 2024 data submitted applications before Order 2023 took effect, meaning its full structural impact remains to be seen.
Regional outcomes vary sharply. According to Wood Mackenzie, ERCOT in Texas leads in both processing speed and project success rates due to its streamlined connect-and-manage queue approach. ISO New England ranks second in success rates but carries the longest processing times due to a delayed shift to cluster-based reviews. CAISO in California has benefited from FERC-approved zonal reforms and a scoring mechanism to advance viable projects, though it reports one of the lowest success rates given its high volume of speculative submissions. PJM, the nation's largest grid operator serving 13 states and the District of Columbia, has lagged the most: FERC ordered PJM on July 24, 2025 to make significant changes to its interconnection process, giving the grid operator 60 days to propose revisions. PJM has approved about 46 GW of interconnection requests for projects yet to be built and expects to finish reviewing an additional 63,000 MW of requests through 2026.
Additional headwinds persist across markets. Fewer new projects entered the queue in 2024, with 32% less battery storage capacity submitting applications compared to 2023, attributed to political uncertainty, elevated interest rates, tariff risk, and local permitting challenges, according to SI2. Lawrence Berkeley National Laboratory's 2025 "Queued Up" report noted that as of end-2024, there were approximately 10,300 projects actively seeking grid interconnection, representing 1,400 GW of generation and approximately 890 GW of storage, with historic withdrawal rates contributing to a 12% decrease in total active queue volume year-over-year.
Outlook
PJM has indicated it expects to begin evaluating new interconnection requests under its reformed process in 2026, with projected wait times of one to two years once the new framework is fully operational. Through July 2025, grid operators had secured another 36 GW in interconnection agreements, putting 2025 on pace to match 2024's record, according to Wood Mackenzie. Lawrence Berkeley National Laboratory researchers noted that while Order 2023 and other reforms represent important measures to reduce interconnection bottlenecks, "it is too early to measure and assess their full impact"-a verdict consistent with the varied trajectories playing out across the country's transmission regions.
For related coverage, see our earlier report on how interconnection and siting delays shaped the Trego 200 MW BESS project near Reno.
