During the week of July 17, three grid operators serving Eastern and Southern regions in the United States set new records for peak demand load, with the New York grid only slighting missing its peak. The grid operators handled the demand by ordering power from peaker plants, which operate a few days a year. In addition, utilities are increasingly stepping down power demand across many locations, known as a virtual power plant, to maintain grid stability, which also keeps energy prices down.
Demand response provider EnerNoc told CNET said it curtailed 1,230 megawatts of power through utilities across the United States in one week.
Grid operator PJM, which serves a region from Illinois to Pennsylvania, amassed between 2,000 and 3,000 megawatts of demand response to meet surging demand in the Mid-Atlantic region,. To give an idea of the amount of power that is, consider that a nuclear power plant generates about 1,000 megawatts, which is about enough to power one million homes.
Mike Wilczek, senior markets editor for North American power at Platts, explains, “Over the last few years, it’s become a bigger and bigger thing, and the technology has helped that. The combination of technology and the sophistication in how grid operators run the energy markets has allowed it.”
In the past, grid operators would contact large energy users individually, but now they work through third-party demand response companies, such as EnerNoc and Comverge. Additionally, consumers can participate in voluntary programs in exchange for reduced rates. Demand reductions can be automatic, such as changing the settings for an air conditioner.
For example, on July 22, hourly demand forecasts identified areas of potential power drain. At 10 in the morning, it contacted third-party demand response companies which aggregate thousands of users who agreed to cut back power usage during peak times and respond within two hours.
PJM spokesman Ray Dotter notes, “What our operators said was to be certain that we have enough reserves, we were going to call in load management to give us a cushion, because we need a reserve for spikes, or if we lose generation. It’s one of the tools we use to manage the grid and the power supplies.”