Virtual Power Plants Face New Grid Test - IEEE Spectrum 

What Are Virtual Power Plants (VPPs)?

The virtual-versus-conventional power plant question is a timely one. Virtual power plants, or VPPs, are networks of devices such as rooftop solar panels, home batteries, and smart thermostats that come together through software to collectively supply or conserve electricity.

Unlike conventional power generation systems, which might crank up one big gas plant when electricity demand peaks, VPPs tap into small, widely disbursed equipment. For example, a VPP might harness electricity from hundreds of plugged-in electric vehicles or rooftop solar panels. Or it might direct smart thermostats in homes or businesses to turn down heat or cooling systems to reduce demand.

How Can VPPs Gain Grid Operator Trust?

But first, VPP developers have to win over grid developers. Benchmarks like the Huels test are crucial to building that trust.

There are four levels to the Huels test. To reach level 1, a VPP must be able to shave off demand from the grid by, for example, successfully scheduling smart thermostats to dial down when the grid faces maximum demand. To reach level 2, a VPP must be able to respond to market and grid data and dial down demand when prices hit a certain level or tap into solar panels or batteries when power is needed. Human decision makers are involved at these levels.

Passing the Huels test comes at level 3. That’s when a VPP can function automatically because it’s proven reliable enough to be indistinguishable from a gas peaker plant–the type of power station that comes online as backup only when the grid is under stress. Passing level 4 involves VPPs acting fully autonomously to adjust output based on a number of actively-changing variables throughout the day.

“The imitation game that Alan Turing came up with was: Can a computer fool an interrogator to think it’s actually human even though it’s a computer,” Hines says. “We propose this idea of a test that would allow us to say: Can we fool a grid operator into thinking that the thing that’s actually solving their problems is this aggregation of many devices instead of a big gas plant?”