Texas’ power grid, operated by the Electric Reliability Council of Texas (ERCOT), now has two virtual power plants qualified and able to provide power to it.
The virtual power plants are a first for the power grid, and the move is part of the Aggregate Distributed Energy Resource (ADER) pilot program that the Public Utility Commission of Texas directed ERCOT to begin developing in June 2022.
The virtual power plants work by virtually aggregating consumer-owned, small energy devices, such as battery energy storage systems, backup generators, and controllable electric vehicle (EV) chargers.
“An ADER represents the aggregation of devices that are located at multiple sites as a single resource,” PUCT explained. “The ADER coordinates the operation of individual devices to collectively reduce demand or feed power to the grid. Through an automated process, the ADER responds to specific ERCOT instructions, allowing participating customers to sell their surplus power to the grid when called upon or reduce use. This is an additional source of dispatchable power for the ERCOT grid.”
The pilot is testing how these energy devices can participate as a resource in the wholesale electricity market.
“Small energy resources found in homes and businesses across Texas have incredible potential to continue improving grid reliability and resiliency by selling the excess power they generate to the ERCOT system,” PUCT Commissioner Will McAdams said in a statement. “It’s a win-win for Texas. Home and business owners get paid for power they supply and consumers in ERCOT get more reliability.”
The addition to the power grid comes as Texas has faced numerous challenges during extreme weather events. In June this year, the Lone Star State reported record-breaking electrical demand during a heat wave. While the power grid was able to keep up with demand at that time, other weather events have knocked out power in the past. In 2021, a deep freeze in the state left many without power for days as an electricity crisis threatened lives and resulted in the deaths of 246 people. Since then, the ERCOT board of directors has seen new leadership.
Recently, Texans have invested in their own energy resources at their homes and businesses, adding backup generators and solar panels connected to battery energy storage systems. These types of energy sources have 2.3 gigawatts of these small resources across the state, and 300 megawatts have been added so far in 2023 alone.
The ADERs are operated by retail electric providers or utilities that sell electricity to homes and businesses, and they must be able to produce at least 100 kW, with each individual device in the ADER being less than 1 MW.
The project has a cap of 80 MW of total participation. PUCT announced the two ADERs have qualified include Tesla Electric customers who have Powerwall storage systems in their homes and have agreed to sell their surplus power in the ERCOT market. They are the first two to participate in the ERCOT wholesale market as ADERs. One ADER is from Houston-area CenterPoint Energy customers and the other ADER aggregates Dallas-area customers served by Oncor Electric Delivery Company.
The pilot project has eight ADERs, totaling 7.2 MW. Of the eight, six have completed the initial registration steps and are in the commissioning process, while two — representing the Tesla Electric customers — have completed required testing and are qualified to participate, PUCT said.
“This ADER pilot project is an example of the electric industry, PUCT and ERCOT developing a pilot to solve issues rather than just studying them. The collaboration achieved the clear goals outlined by the Commission and is a model for future projects at the PUCT,” PUCT Commissioner Jimmy Glotfelty said in a statement. “We have a market in ERCOT that allows us to innovate and learn through real-time experimentation with real-world impact.”