
It’s been a busy few months for Durham-headquartered FlexGen. Last week, the energy management software platform made headlines for raising a $100 million Series C round. And earlier in the summer, the startup made the 2022 Triangle Tweener List.
Kelcy Pegler, FlexGen’s CEO who joined the company last year, said the startup has long since been ahead of its time. Founded around 12 years ago, FlexGen entered a market that was not yet at the energy storage levels that FlexGen envisioned. But, now in 2022, the company is well-positioned to be right at the intersection of grid transitions, he said.
Renewable energy sources continue to grow as a percentage of energy generation, but given that (for instance) solar energy only creates energy when the sun is out and wind energy needs a breeze, utility-scale energy storage via giant batteries is crucial to the modern power grid to help even out supply.
Investors have increasingly been taking note of FlexGen’s solution as it raised a $150M Series B just last August, which means the company has banked a whopping $250M total in less than 12 months.
“Coming off the heels of that (Series B) fundraise, we’ve been awarded a lot of contracts and projects,” said Pegler. “This (Series C) fundraise enabled us to keep pace with the explosive growth that our business is in the midst of.”
FlexGen recently made its new headquarters in the American Tobacco Campus in Durham and is unveiling a new innovation center to test battery technology and hardware in a lab setting. These next-generation products will be critical for tomorrow’s grid, Pegler said.
“This capability that we had for the last decade-plus is really in demand,” Pegler said. “And we’re excited to be able to provide value to our customers.”

Making their home in the Triangle was a conscious choice, according to Pegler, who said FlexGen has benefited from the talent here.
“We chose the Triangle and specifically Durham because of it being one of—if not the most—brilliant ZIP codes in the country,” Pegler said. “We love the fact that there’s so much high-horsepower intelligence married with really purposeful passion in the area.”
Just 18 months ago, Pegler said, FlexGen only had 40 employees, meaning it has almost quadrupled to its current 150 in that span. As the company adds additional growth-oriented managers and leaders, they are hoping to scale to new levels.
And with such a rapidly growing team, Pegler said FlexGen has leaned into the hybrid work model, allowing employees to choose how they work best and encouraging a strong work-life balance.
“We have really brilliant software system engineers, and we take pride in recruiting the best and the brightest of this really nascent space that really needs intellectual horsepower,” Pegler said. “We’ve really leaned into the hybrid work style where I think we match our employees’ desires to both have workstations in a concentrated office and then have the balance and freedom of remote work. It really struck the right tone.”

When it comes to its mission, Pegler said FlexGen sees itself enabling today’s energy transition by providing utility-scale storage projects integrated with traditional and renewable power generation.
“With battery storage, we see ourselves as a central component to bridging the grid of yesteryear together with the grid of tomorrow,” Pegler said. “And we recognize that there has never been a more important time to do this.”
As FlexGen puts its new funding to use, the startup has established a high market demand and is focused on carrying out this mission, Pegler said.
“It’s really just about executing now,” Pegler said. “The demand is here. The projects are scheduled. It’s really executing great projects for our customers and continuing to build out our technology capabilities ahead of what our customers’ wants are, so that as use cases evolve, we continue to be skating to where the puck is going.”