
Amid skyrocketing demand from residential growth and large industrial loads, an electric cooperative near Atlanta is helping test advanced long-duration energy storage technology to enhance reliability, maintain affordability and support new energy resources.
Covington, Georgia-based Snapping Shoals EMC welcomed the opportunity from technology developer Stryten Energy in neighboring Alpharetta to demonstrate a small vanadium redox flow battery (VRFB) for safely storing electricity for up to six hours.
“The state of the electric grid today is evolving every day, and our equipment has to be able to change and respond much quicker than electric systems in the past,” said Shaun Mock, CEO of Snapping Shoals EMC.
“The Holy Grail is long-duration energy storage. Having a piece of equipment like a long-duration battery can help stabilize fluctuations and enable us to provide better service and manage costs.”
The VRFB system at Snapping Shoals is the first system manufactured and installed in the state of Georgia. While VRFB is in use in Australia and China, there are only a handful of such systems in the United States, making the co-op’s pilot significant to the advancement of the technology, Stryten said.
“Snapping Shoals has just been a tremendous help to us to take that first step and the second step and start to prove to the world that we need a new technology,” said Scott Childers, vice president of essential power at Stryten.
So how does VRFB work and what makes it different from the lithium-ion batteries that utilities across the country are using to run microgrids, shave energy demand peaks and fill in generation gaps?
The completely liquid-based VRFB is composed of two tanks of electrolytes—one positively charged, the other negatively charged—and a stack assembly where ion exchange and electron movement from one tank charges the system. The battery’s power is determined by the quantity of stacks, and its duration is based on tank size.
Childers likens the VRFB’s setup to that of an automobile. “If you want more horsepower, you get a bigger engine. Here, the number of stacks that you have in the system gives you your power that can be discharged at a given time,” he said. “If you want longer duration or more total energy, you just get bigger tanks filled up with more liquid.”
Unlike lithium-ion batteries, a VRFB is scalable to meet a utility’s growing needs. Stacks and tanks can be reconfigured independently to increase the amount of power and storage duration for up to 10 hours. A lithium-ion battery can store electricity for one to four hours and must be fully replaced with a larger one or multiple batteries to increase energy storage capacity.
Another significant difference is that a VRFB can last up to 20 years without losing capacity despite multiple daily charges and discharges. Lithium-ion batteries tend to be replaced within four years due to more wear-and-tear with each use.
“There’s really no limit to VRFB’s capacity,” said Childers. “It’s really kind of a question of how big a field do you have to put tanks in.”
Snapping Shoals offered clean concrete generation pads for the company to install a 20- kilowatt/120 kilowatt-hour system when it agreed to pilot the battery technology last August.
“This is what cooperative innovation looks like when the grid has no time to wait,” said Jennah Denney, senior program manager of technology integration at NRECA. “As demand accelerates from growth, electrification and large loads, co-ops are actively testing solutions that can scale, adapt and perform over decades.”
As new houses, businesses, rooftop solar, electric vehicles and large industrials, including data centers, proliferate across the co-op’s system, Mock envisions multiple applications of the technology to reduce the strain on the grid.
VFRB may provide prepacked solutions for redundancy to hospitals, schools or large industrial or commercial consumers. It can also help reduce outage times, blunt power market price spikes and back up intermittent renewables, he said.
“The flexibility of our power supply structure enables us to explore new technologies,” said Mock. “The world is changing, and we all need to have every available resource to us in order to meet the demand.”
Cathy Cash is a staff writer for NRECA.




























































































































































































