A few years ago, battery energy storage was more demonstration than application.
But much of that changed in 2017 as Duke Energy began moving forward with energy storage projects that will help selected parts of the company’s territory. With renewable energy growing across the company, improved battery storage is needed to work in conjunction with wind, solar and the energy grid to provide reliable service to customers.
In Indiana, Duke Energy is planning to install a 5-megawatt battery storage system and 3 megawatts of solar that will provide grid services, along with operating as a microgrid, at the Indiana National Guard's Camp Atterbury training operation. The microgrid – connected energy sources that can serve a customer on its own – will help with reliability and grid security at the camp.
Duke Energy has also included 75 megawatts of energy storage in its 2017 Integrated Resource Plan in the Carolinas.
In Asheville, N.C., a 9-megawatt lithium-ion battery system will be placed at a Duke Energy substation in a local community. The battery will primarily be used to help the electric system operate more efficiently. It will provide energy support to the electric system, including frequency regulation and other grid support services.
In Hot Springs, N.C., a 4-megawatt lithium-ion battery system will help improve electric reliability for the town, along with providing services to the overall electric system.
Duke Energy has a smaller battery installation in Haywood County, N.C. The company has a 95-kilowatt-hour zinc-air battery and 10-kilowatt solar installation serving a remote communications tower on Mount Sterling in the Smoky Mountains National Park. During the aftermath of Hurricane Irma, the installation’s microgrid operated without an outage to the facility.
As for the future, a settlement in Florida will allow the company to invest in up to 50 megawatts of battery energy storage in the state over the next five years. Duke Energy is currently evaluating sites for these deployments.