Background
Ameren Illinois, as a result of their Multi-Year Integrated Grid Plan, needed to explore flexible interconnection options and identify which options could be effectively implemented. Flexible connections is a concept that incorporates new control systems or operational capabilities to connect new loads and/or DER to the distribution system more efficiently. The benefits include faster energization and lower connection costs, however, study complexity does increase.
Challenge
Flexible interconnection is still a relatively nascent topic within the distribution space. Existing efforts have focused primarily on communications and control-based dynamic flexible connections, which require significant investments in new technology.
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Solution
EPE expanded flexible interconnection to cover both load and distributed energy resource (DER) connections and to encompass a wider variety of flexible interconnection methods, including static methods such as limited import/export connections, schedule-based connections, and staggered connections. EPE's approach focused on the technical, process, and regulatory feasibility of each method to determine which methods were reasonable for Ameren to utilize in the short term and to identify changes needed to support more advanced methods in the future. EPE also explored how flexible interconnection fits within the broader ecosystem of DER Orchestration to provide distribution and bulk power services.
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Results
Ameren Illinois filed their Flexible Interconnection and DER Orchestration Report (a leading resource in exploring flexible interconnections) in September of 2025, which documents implementation details and pathways for each flexible interconnection method for load and DER applicants.