FERC on March 20 approved Duke Energy’s compliance filing with Order 2023, which revised the commission’s pro forma generator interconnection rules to speed up queues around the country (ER24-1554).
The changes to Duke Energy Carolinas’ and Duke Energy Progress’ large generator interconnection procedures (LGIP) and small generator interconnection procedures (SGIP) will go into effect Nov. 1, 2025, as requested, with the utility having to make an additional compliance filing within 60 days of the order to make some minor changes.
Duke proposed to adopt FERC’s pro forma large generator interconnection agreement (LGIA), pro forma LGIP, pro forma small generator interconnection agreement and pro forma SGIP. Much of the other parts of Order 2023 were also adopted directly, but Duke also proposed some variations, which is allowed as long as they are consistent or superior to its baseline rules.
The utility had already implemented a cluster study process before Order 2023, which it proposed to keep in place but change some of the timing requirements to better align with FERC’s new requirements.
It proposed to cut its 180-day cluster request window down to 45 days but leave the customer engagement window at 60 days, the Phase 1 Cluster Study deadline at 90 days, the Phase 2 study at 150 days and the as-needed Cluster Restudy at another 150 days. Individual facility studies are required to be done in 90 days or 180 days based on the interconnection customer’s choice, instead of 150 in the current rules.
The two-phase study process has Duke study power flow and voltage in the first and then stability, short circuit and reactive capability in the second. The process allows the utility to work through the queue more quickly and efficiently and cuts the likelihood that it will need to do restudies, making it better than the default in Order 2023, it told FERC.
“We find that Duke’s two-phase cluster study process overall satisfies the ‘consistent with or superior to’ standard by providing interconnection customers with Phase 1 study results and an opportunity to withdraw earlier in the study process, thereby increasing the speed and efficiency of the Phase 2 study,” FERC said. “Duke’s proposed two-phase process occurring over 90 days is, in this respect, faster than the commission’s single-phase pro forma process, which takes an additional 60 days to conduct the cluster study and provide results to customers, after which they would have their first opportunity to withdraw from the queue.”
Duke’s proposal gives customers an earlier look at network upgrade costs, which allows them to make critical decisions about whether to move forward earlier in the process, the commission said.
Some intervenors were worried that the tight study deadlines left little room for error, but Duke said it has adopted all the aspects of Order 2023 designed to mitigate restudy risk.
“Moreover, Duke presents historical data showing that large percentages of its customers withdraw after Phase 1, and that retaining its two-phase process provides an opportunity to withdraw earlier in the process,” FERC said. “In turn, we agree that a cluster study process that maximizes the likelihood of early withdrawals will also minimize study and queue administration costs for all customers.”
Duke’s proposed withdrawal penalties increase at each stage of the process, which is in line with the structure adopted in Order 2023, FERC said. It had to tweak that to fit its two-study process, requiring interconnection customers dropping out after Phase 1 to pay twice its actual allocated costs of all studies performed up to then, and those that drop out after Phase 2 to pay 5% of estimated network upgrade costs and then increasingly higher shares of network upgrade costs later in the process.
The utility removed penalties for projects not picked in resource solicitation processes, which FERC said was superior to its pro forma process by cutting barriers to entry to the queue.
