Polar vortex became the first catchphrase of 2014 in the United States. It was no joke, though, as the phenomenon led to record low temperatures and several deaths around the country. The cold snap also took its toll on the electric grid, leaving hundreds of thousands of people without power across a large swath of the nation. There could have been even more outages had demand response (DR) not been at the disposal of system operators as a step in their emergency procedures.
PJM, ERCOT, and NYISO all set new winter peak demand records due to the heating requirements that the frigid temperatures required. When you combine record demand with power plant and transmission line outages that can be caused by the cold weather, electric grids can quickly get into emergency situations where they need to call on reserves to prevent forced load shedding, otherwise known as brownouts or blackouts.
Prior to this winter, ISO-NE activated its DR system in response to grid and weather conditions during the winter in each of the past 2 years, and ERCOT called one winter event a few years ago, while PJM and NYISO have never had winter DR activations. ISO-NE called an event this past December as well – on a Saturday night no less – due to generator outages, but it survived the vortex without having to implement DR. The rest of the regions all dispatched their DR resources at some point during the vortex conditions, and all of them succeeded in avoiding further emergency steps like blackouts.
ERCOT was the first region to call DR as the cold wave swept East across the country. It activated its contracted DR customers and put out a general conservation notice to all consumers.
PJM actually deployed DR twice in 1 day due to higher-than-anticipated morning load ramp and an evening peak load spike, as seen in the chart below.
PJM Load Curves on January 7, 2014
NYISO dispatched DR for a 6-hour stretch and took the additional step of encouraging consumers to conserve electricity by lowering thermostats and turning off major electric appliances.
It’s too early to get verified performance results, but the main test was passed by avoiding blackouts.
The winter is hardly over yet, so there could be more DR activity coming up this season. The vortex may have been a rare event, but all ISO/RTOs will now take a much closer look at its DR performance requirements for the winter. PJM is in the process of including an annual DR product that would require mandatory participation year-round, as opposed to its traditional summer-only program. ERCOT will analyze whether it should increase payments for winter peak periods to incentivize more participation. ISO-NE was preparing to handle winter grid reliability prior to this season due to the shortage of natural gas pipeline infrastructure in the region, which could lead to fuel shortages for gas-fired generators. It developed a special winter DR program, which is intended to be implemented prior to the regular emergency DR program, to shore up the system before it reaches that stage.
This new reality will put a lot of stress on DR as an operational resource. A large portion of typical DR is based on air conditioning curtailment, which is not much help in the winter. Some large industrial facilities have stable load year-round, and some industries, like ski resorts, have more load in the winter. However, the majority of commercial and residential customers will not be able to fully participate in an annual DR program. DR providers will have to be cognizant of where customers’ limits lie, and create new technologies and strategies to minimize pain and maximize performance.
Tags: Climate Change, Demand Response, Extreme Weather, Smart Utilities Program, Utility Innovations
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