When Super Storm Sandy struck New York in October 2012, the damage to the state’s electric utility infrastructure was devastating, overwhelming repair and restoration efforts by distribution system operators. A new study shows the extent of the challenge faced by the upstate New York distribution grid and suggests what might be done to make the system more resilient against future storms.
The study, which required more than three years to complete, examined power failures that affected more than 650,000 customers from four major service regions. The study showed that failures affecting small numbers of customers accounted for more than half the outage impact, challenging a traditional recovery strategy that prioritizes repairs to substations and other major facilities. The research, published in the journal Nature Energy, is believed to be the largest detailed study of failure reports for distribution grids.
“System failures can affect large numbers of customers even if they occur at the distribution level of the grid and do not cascade,” said Chuanyi Ji, an associate professor in Georgia Tech’s School of Electrical and Computer Engineering. “Together, these local failures can have a big non-local impact on customers. These findings are drawn from large-scale data analytics — a relevant area for energy infrastructure.”
The top 20 percent of distribution grid failures accounted for more than 80 percent of the customers affected. But even failures that each affected relatively small numbers of customers added up. A large portion — 89 percent — of small failures, represented by the bottom 34 percent of customers and commonplace devices, resulted in 56 percent of the total cost of the storm’s 28 million customer-interruption hours. — John Toon