Can a grid operator tell the difference between a virtual power plant and a traditional one?
That’s the idea behind the Huels Test, a framework developed by EnergyHub to answer a simple but consequential question: when does a distributed fleet of customer devices become reliable enough to function like a power plant?
Passing the test means more than just aggregating thermostats or batteries. It means delivering predictable, repeatable performance that utility planners and operators trust enough to rely on during system peaks. And it’s no longer theoretical.
During a series of brutal winter cold snaps across the Southeast this year, Duke Energy leaned on tens of thousands of connected devices — smart thermostats, batteries, and water heaters — to help manage record-breaking winter peaks. Together, they formed a virtual power plant that the utility could dispatch when the grid was tight.
In this Frontier Forum, Stephen Lacey talks with Stacy Phillips, Managing Director of Customer Load Management at Duke Energy, and Seth Frader-Thompson, president and co-founder of EnergyHub, about the spectrum of virtual power plants.
They discuss how VPPs are evolving from traditional demand-response programs into operational grid resources, and what still needs to change before utilities treat them exactly like conventional power plants.
This is partner content, brought to you by EnergyHub. This conversation was recorded live as part of Latitude Media’s Frontier Forum with EnergyHub. Watch the full video here.
EnergyHub works with more than 160 utilities across North America to build and scale virtual power plants using its Edge DERMS platform. Read EnergyHub’s white paper outlining the VPP maturity model and discover what VPPs can do for your grid.


