Get Ahead of the Curve: Key 2025-2026 Cluster Windows in the SERC Region

If you’re planning to interconnect a project in the Southeast, now is the time to get moving. Several important cluster windows are fast approaching in the SERC region, and developers who act early will be positioned for greater flexibility and less risk. 

Here’s what’s coming and how we can help. 

Download the 2025 SERC Interconnection Playbook 

Immediate Opportunity: TVA’s Resource Solicitation Cluster (RSC) 

 The TVA RSC bid deadline is May 30, 2025. This initial step does not require technical documentation, just a clear narrative of your company and project. However, if you are selected for the shortlist (to be released June 27), you’ll need to move quickly. 

• Cluster window opens July 1, 2025 and remains open for 45 days. 
• All deficiencies must be resolved before the window closes. 

TVA requires PSSE and PSCAD model development and benchmarking. We recommend that serious contenders begin their modeling and study prep before shortlist notifications are sent. While there’s some risk involved, the upside is significant: if your project isn’t selected, we can help you update and resubmit into TVA’s 2026 annual cluster, which opens January 15, 2026. 

We’ve already begun working with three major firms this week, and we’re ready to support others planning to participate. 

Looking Ahead: Dominion’s Annual Cluster 

Dominion’s cluster window opens August 15 and closes September 29, 2025. This is a tight submission period, so early preparation is key. We encourage interested developers to begin assembling application materials now to avoid delays. 

2026 SERC Cluster Timeline Preview 

Early 2026 is shaping up to be a high-activity period across multiple SERC utilities. If you’re looking to queue up projects in these regions, December 2025 is the ideal time to begin working on application packages. Here are the key windows: 

• Santee Cooper: January 1 – May 31, 2026 
• Duke Energy: February 1 – March 18, 2026 
• TVA Annual Cluster: January 15 – March 1, 2026 
• Southern Company (SOCO): March 1 – April 15, 2026 

The Bottom Line: Start Now 

At EPE, we can help you get ahead, whether you’re submitting to TVA’s RSC, preparing for Dominion, or positioning for 2026’s broader SERC queue. We’re already supporting some of the industry’s top developers, and we’re ready to move quickly on your behalf. 

Let’s talk now so we’re not racing the clock later. Contact our team using the form below.