EPB of Chattanooga Deploys Battery-Based Microgrids for Savings, Resilience

Why It Matters

The initiative cuts peak‑demand costs and bolsters grid reliability, positioning EPB as a model for utilities seeking resilience through storage and microgrid technology.

Key Takeaways

• Five microgrids add 29 MW, 58 MWh capacity
• EPB targets 100‑150 MW storage within three years
• DOE funds $32.3 M for grid upgrades and storage
• Oak Ridge platform enables dynamic, nested microgrid control
• Storage cuts peak demand charges, saving utility costs

Pulse Analysis

EPB’s aggressive rollout of battery‑based microgrids reflects a broader shift in the U.S. utility sector toward distributed energy resources that can both lower operating expenses and enhance system resilience. By storing energy locally, EPB can shave the hourly peak demand that drives a substantial portion of its purchase costs from the Tennessee Valley Authority. This strategy not only reduces the utility’s exposure to volatile demand‑charge tariffs but also aligns with federal objectives to modernize the grid and mitigate the impacts of extreme weather events.

The partnership with Oak Ridge National Laboratory adds a sophisticated control layer that differentiates EPB’s approach from conventional storage deployments. The upcoming microgrid platform will dynamically adjust the size and hierarchy of microgrid clusters, allowing “nested” configurations that can isolate critical loads during outages while still supporting broader distribution needs. Such flexibility is crucial for EPB’s mixed urban‑rural service area, where demand patterns and outage risks vary dramatically across the network.

Beyond immediate cost savings, EPB’s program serves as a template for other municipal utilities confronting similar challenges. Federal backing through the Department of Energy’s $32.3 million grant underscores the policy momentum behind grid hardening, pole replacement, and undergrounding projects. As battery technology becomes more affordable, utilities that integrate advanced microgrid controls will likely capture greater value, driving industry standards toward more resilient, customer‑centered power systems.