Battery storage is showing signs of being a major factor in the future energy mix, and Duke Energy is one of the leading companies pushing its development.
Over the next 15 years, the company has more than 400 megawatts (MW) of battery storage planned, with new projects being put online and announced around the country. That’s about 10 times more than Duke Energy has online today.
In addition to simply storing energy for use at another time, battery storage can help expand the development of renewable energy and support a modernized energy grid.
The company announced plans to bring 300 MW of battery storage in the Carolinas online over the next 15 years – a $500 million investment.
In western North Carolina, the company has one battery project online in Haywood County, with two others set to be online in 2020 in Buncombe and Madison counties.
In Indiana, Duke Energy is planning to install a 5-MW battery storage system and 3 MW of solar that will operate as a microgrid at the Indiana National Guard's Camp Atterbury training operation. In Maryland, a similar microgrid project went online in 2018 at two government facilities.
The microgrid – connected energy sources like solar and a battery – can serve a customer on its own. It can also help with reliability and grid security.
Battery storage can not only store excess energy for when its needed, it can also control energy flow inside power lines, which results in fewer outages and flickers.
For example, clouds moving over solar panels and winds changing throughout the day lead to fluctuations in energy supply. For the energy grid, which depends on a perfect match between energy produced and customer demand, it’s difficult to manage.
Even a slight change in frequency or voltage can cause interruptions in power to a home or business. When needed, batteries can react in a fraction of a second to absorb the swings and stabilize the flow of energy.
Of course, batteries are not the only energy storage method. The company has more than 2,000 MW of pumped storage hydro power. Over the next few years, Duke Energy will increase the capacity at its Bad Creek facility in South Carolina by more than 300 MW as it upgrades the facility.