The city of Chattanooga and EPB on Thursday celebrated the completion of the “Power to Protect” microgrid based at the Chattanooga Police Services Center and Fire Department administrative headquarters at 3410 Amnicola Hwy. The new microgrid can generate and provide power in an emergency and sustain operations 24/7/365 with enough energy for the fire and police functions at the location to respond to the needs of the Chattanooga community indefinitely.
Functions located at the Chattanooga Police Services Center and Fire Department administrative headquarters and served by the microgrid include additional services such as SWAT team, homicide, Chattanooga Fire Station 10, radio control center, city camera surveillance, and other critical communication infrastructure. Fortunately, there has been no need to use the microgrid in an emergency, although tests take place regularly, said officials.
“EPB is a national leader in Smart Grid technologies, and we’re fortunate to have their level of experience locally to protect our essential services in a sustainable manner that reduces cost and waste and ensures our first responders’ ability to protect our city at all times,” said Chattanooga Mayor Tim Kelly. “We’re glad to add Power to Protect to a long list of successful Smart City innovations.”
EPB’s Smart Grid provides two pathways for power to reach the Chattanooga Police Services Center and Fire Department administrative headquarters, so the new microgrid will serve as the third line of defense should widespread outages affect Chattanooga.
“Facing an outage in an emergency is a place none of us want to be, especially as first responders,” said Chattanooga Fire Chief Phil Hyman. “From the Easter 2020 tornadoes to this spring’s windstorms, we’ve seen how changing weather impacts our safety, and this microgrid will prepare us to be resilient in any event.”
To ensure comprehensive power resiliency, EPB also relocated a power pole from the front to the back of the building to avoid damage from possible wrecks in the future on the busy Amnicola Highway corridor.
“Our technology depends on electricity, so it’s essential we don’t lose it,” said Chattanooga Police Chief Celeste Murphy. “It’s a relief to know we won’t have to worry about how we’ll access power should we lose connection to the Smart Grid.”
The Power to Protect microgrid includes two main generation and storage systems that reduce costs and allow both the city and EPB to recoup their investments more quickly:
Generation: The city of Chattanooga purchased a 200-kilowatt diesel generator and 155 kilowatts of solar panels (installed on the building roof); these were installed “behind the meter” and reduce the amount of energy consumed at the location, lowering its monthly bill by roughly 20 percent.
Storage: EPB invested in a 500-kilowatt battery to support the microgrid and other grid services; the battery is installed “in front of the meter” so it can be used to shave peak load during extremely hot or cold weather, reducing TVA’s peak demand charge to EPB and keeping energy costs lower for local residents and businesses. (EPB does not shave peak load if severe weather is in the forecast; batteries are charged to capacity so they are prepared for an emergency.)
Because utilizing energy storage reliably reduces peak demand charges, EPB’s investment will pay for itself within six to seven years and will continue to provide value well beyond the cost of purchasing and installation, said officials.
"EPB is committed to establishing microgrids like this throughout our community because they further improve the resiliency of Chattanooga’s power grid,” said EPB President and CEO David Wade. “This project is a great example of how we’re using microgrid technology to enhance EPB’s local energy mix while providing customized energy solutions to address the specific needs of customers in different areas.”
EPB’s Smart Grid has 1,200 smart switches, sensors and other devices on a 9,000-mile fiber optic backbone to reroute power automatically when a disruption is detected. EPB continues to expand the EPB Local Energy Mix with distributed energy resources across its 600-mile service region to improve power resiliency, business continuity for critical community resources and reduce costs for customers through peak demand management. Several projects are being planned now, particularly in rural areas that take additional time to reach should the Smart Grid be unable to reroute power.