Advanced Energy Commissions New Solar-Plus-Storage Sites for North Carolina’s Electric Cooperatives

Batteries are coming to your grid soon! One of the more exciting and impactful grid modernization technologies is utility-scale battery storage. Battery storage can give utilities greater flexibility when operated alongside renewables, lower peak demand, flatten the daily demand curve and increase resiliency to keep everyone’s power on.

For North Carolina’s Electric Cooperatives, battery storage and environmentally friendly solar generation are critical to achieving their Brighter Future vision.

“Cooperatives in North Carolina are working together to integrate innovative energy technologies that ensure our consumer-members continue to benefit from reliable, affordable and increasingly sustainable electricity,” said Amadou Fall, chief operating officer of North Carolina’s Electric Cooperatives. “Energy storage is a solution that enables us, as a Distribution Operator, to gain the most benefit from intermittent resources like solar, save costs and reduce emissions through demand response, and add local grid resources for resilience and reliability.”

The cooperatives installed their first battery in 2017 on the barrier island of Ocracoke as part of the Ocracoke microgrid. The co-ops now operate four microgrids in the state, with a fifth coming online this year. In the past year, the co-ops have also begun adding solar-plus-storage sites to the grid. One of the benefits of combining solar and battery storage is that the battery can store energy produced by solar during periods of low demand and continue to feed the grid even when the sun isn’t shining or during periods of greater demand, when wholesale electricity prices are higher.

So far, five cooperative solar-plus-storage sites — three in Randolph EMC territory and two in Four County EMC territory — are being commissioned in Advanced Energy’s Distributed Energy Resource Commissioning process. Five additional locations are under development and will be brought online this year. These will connect to the Tideland EMC, Pitt and Greene EMC, South River EMC, Pee Dee Electric and Wake Electric distribution systems.

The sites have comparable characteristics. Grid-scale commercially available battery storage paired with a similarly sized solar field add flexibility to either store or generate energy, and communication networks enable the cooperatives to remotely adjust battery functions and responses as needed through Distributed Energy Resource Management Systems (DERMS). 

Ultimately, these sites will be able to provide power to homes, businesses and industry, and they may allow the cooperatives to defer costlier upgrades to power plants and substations to help keep electricity rates down, which is part of the cooperatives’ mission as not-for-profit energy providers.

Advanced Energy’s role is to help get them up and running and connected to the grid. We are an important step along the way — inspecting the quality of the work and ensuring that all required codes, standards and regulations are adhered to. We also confirm that the sites will be safe for personnel and the operation of the grid.

“We are grateful for Advanced Energy’s expertise in inspecting and testing these battery storage systems, and we appreciate their commitment to ensuring that our interconnections to distribution cooperatives’ grids are configured correctly and safely,” Fall said. 

In addition to utilizing battery storage to lower costs and enhance resilience and reliability, North Carolina’s Electric Cooperatives are looking at other use cases to support the grid, including:

  • Volt/VAR Functions: Controls that allow the battery to react to the grid voltage and current, and respond with reactive power when appropriate
  • Regulating Output: Reacting to grid conditions to avoid overgeneration and associated issues
  • Ramp Rate Control: The ability to change the speed at which the battery storage changes output to improve distribution system conditions
  • Voltage and Frequency Ride Through: Allowing the battery storage to stay connected to the grid and stabilize a grid if it were to briefly fall out of an acceptable range for voltage or frequency

Incorporating these functions and gathering data and experience with battery storage will keep North Carolina’s Electric Cooperatives up to date with the latest grid support capabilities and prepare them to increase utility-scale battery storage in the future. These efforts are critical as North Carolina’s Electric Cooperatives works to evolve the grid and ensure that cooperative consumer-members across the state continue to have safe, affordable, sustainable, reliable and resilient power.