PJM Finds Multiple Causes for Winter Storm Elliot Failures

“Once in a decade” Winter Storm Elliot revealed serious vulnerabilities in the region’s power generation system. A preliminary analysis conducted by the PJM Interconnection found that the extreme nature of the storm, generator issues, and lack of access to fuel contributed to the “unacceptable” failures. Winter Storm Elliot was a bomb cyclone storm that hit Pennsylvania on Dec. 23, 2022, causing the most drastic daily drop in temperature in the last 10 years. Temperatures fell 29 degrees in just 12 hours, going into negative territory. The storm’s high winds, snow, and freezing temperatures led to power outages for those serviced by the PJM Interconnection. PJM Interconnection is a regional transmission operation (RTO) that coordinates the electricity market for 13 states, including Pennsylvania, and the District of Columbia. Some 70 percent of the outages, totaling 32,473 megawatts (MW) of lost power, were from generation failures at natural gas-fired plants. Natural gas is the most commonly used fuel among PJM power generators, making up just under half of the fuel mix. PJM launched an investigation into the breakdown, and found several factors that could have caused or exacerbated the problems. PJM reports that the cold led to extremely high and sustained peaks in electricity demand from Dec. 24 through 25, overshooting initial forecasts. The cold also created problems for natural gas-fired generators, which experienced a multitude of mechanical issues at their plants and supply chain problems upstream. Temperatures reached their coldest on Dec. 24, during which the PJM reports that 46 gigawatts (GW), or 23 percent of generation capacity, was offline. PJM plans for extreme weather events, coordinating with their generators to prepare for increased demands, and had done so in this case. However, the original forecasted demand of 127 GW of power was lower than the real demand by approximately 10 percent. Compounding the problem, many PJM generators were experiencing outages, leaving the additional power demand unmet. Issues upstream from the generators contributed to the outages as well, such as the availability of natural gas. Frozen compressor stations along crucial pipelines prevented the normal flow of the available gas to generating stations.

However, generators who failed to provide service for PJM customers could be facing $1 billion to $2 billion in non-performance penalties for their lackluster performance due to the agreements between the parties. PJM is continuing its analysis of their operations and expects to release the results in April.