Back-to-back powerful hurricanes have produced yet another stress test for the United States electrical grid, perhaps kicking the urgency of finding long-term remedies for deficiencies up another notch.
Hurricane Helene, and fast on its heels, Milton, tore across the Southeast and Florida recently. They brought brutal winds and massive flooding that downed power lines and submerged substations, leaving huge swaths of the region without power. The scale of devastation (extending to inland areas thought insulated from hurricane-force storms) put an exclamation point on the vulnerability of an aging, exposed and overloaded electrical grid to the prospect of ever more powerful, large and frequent storms, a leading cause of power outages (see Figure).
But the fall storms may also have helped further bolster the concept of distributed power generation as part of the answer to dealing with a possibly stormier future. Anecdotally, such systems came to the rescue. Two built partly for the purpose of providing power in the event of grid power loss proved their value, at least partially.
In Hot Springs, N.C., near the bullseye of torrential rains and flooding spawned by Helene, a microgrid that went live just 18 months earlier provided power for long stretches to the town of 500 while surrounding areas were blacked out. Generating power with a 2MW (AC) solar array connected to a 4.4MW battery storage facility, the blackstart-capable microgrid was built by Duke Energy to provide “islanded” power with no grid linkage to an isolated community frequently hit with power outages. Lacking battery for long stretches, it didn’t perform flawlessly in the storm’s aftermath but largely met expectations.
In a LinkedIn post, Duke’s distributed energy manager, Jason Handley, said the microgrid at one point had to be “restored,” after which time it operated daily, providing power after the substation feeding the town “washed away,” severing its tie to Duke’s grid. Using only batteries and solar, we have been able to power the downtown area of Hot Springs continuously.”
In Florida, a six-year-old residential community of 10,000 built around sustainability didn’t lose power during Hurricane Milton thanks to a 150MW solar farm paired with modest battery capacity that kept feeding power to structures through underground transmission lines sheltered from winds. Babcock Ranch on the state’s west side has proven its energy resiliency in past hurricanes, elevating it as a state-blessed, temporary shelter-of-choice for some 2,000 people who evacuated neighboring areas destined to lose power, and worse, when Milton struck.
Stronger and more frequent storms will enhance the appeal of distributed generation projects, but they’re only part of the puzzle. An array of other approaches will be needed if — as some predictions lay out — climate change brings a new normal to hurricane patterns.
Recently, Pacific Northwest National Laboratory (PNNL) and Electric Power Research Institute (EPRI) researchers gamed out a scenario in which strong and wetter storms raise the future risk of power outages 50% in some areas of the United States. Their research, called Climate READi, however, didn’t fully factor in possible grid resilience measures that could reduce the risk, such as burying or elevating transmission lines, more distributed generation, increased use of renewable power and overall grid-hardening measures.
A comprehensive approach is reflected in the U.S. Department of Energy’s flowering program to support grid infrastructure improvements. Its Grid Resilience and Innovation Partnerships program is funneling $10.6 billion to projects that improve the resilience of the power infrastructure to climate change and extreme weather. Numerous projects are in the pipeline and others have been approved, including six worth $600 million announced in the wake of the Helene and Milton storms that target infrastructure in impacted areas. Work will include installation of advanced conductors, deployment of self-healing devices, technology to improve dispatching of field teams, line upgrades, and reconductoring of transmission infrastructure.
The prospect of a more at-risk electrical grid is also spawning more research into novel ways of reducing that risk. Researchers at Potsdam Institute for Climate Impact Research in Germany have developed a model based on the Texas electrical grid showing it may be possible to identify — and harden — specific critical points in an electrical grid that almost invariably lead to cascading power outages. That knowledge could enable utilities to focus their efforts on storm-proofing as little as 1% of an electrical system and thereby significantly reduce the chance of hurricane-induced blackouts.
Another approach to better gauging and managing storm-induced grid-failure risk involves the use of artificial intelligence (AI). A recent New York Times article notes that a recently formed company, Rhizome, is marketing a tool to utilities that uses AI to help them better understand where to target efforts aimed at limiting the occurrence and impact of hurricanes on their systems.
Facing the likelihood that more powerful and frequent storms are going to be a reality, the tool boxes utilities will have to dig into to limit grid damage and subsequent power outages are destined to become fuller.
