Can Underground Power Boost Urban Resilience?
Moving power lines underground would reduce outages, but is a complicated and expensive prospect
In early January, a storm dumped over a foot of snow on my home state of Virginia, knocking out power. Although urban areas recovered quickly, rural and suburban parts of the state, such as where I’m based in Albemarle County, went 3 days without heat, internet, or adequate road plowing, leaving many vulnerable. Power outages from such weather—not just snowstorms, but hurricanes, tornadoes, and heavy rain—are rampant nationwide. One way to avoid this is by burying power lines. Why isn’t that more common?
The problem is getting worse in the U.S. According to Popular Science, outages impacting 50,000 or more clients “grew ten times more common from the mid-1980s to 2012.” In the most extreme cases—such as 2018’s Hurricane Florence—over 1 million people lost power. Outages are also longer here, in some areas than overseas; one researcher found that in the average year, Midwestern areas have over 90 minutes without power, compared to four minutes in Japan.
The main reason for outages is that storms either knock down power lines or knock things onto them. Repairing them leads to many electrocution deaths, notes attorney Jeffrey Feldman. So it seems good that lines would go underground.
It’s uncommon, though. As of 2012, research by the Edison Electrical Institute finds that only about a quarter of new utility line construction in America took place underground. The majority of power infrastructure remains above ground.
Florida has begun moving utilities underground substantially. The state began piloting below-grade construction in the late 2010s, using a method known as horizontal drilling. By November 2020, according to Florida Today, the state’s utility “had completed more than 160 Storm Secure Underground Program projects throughout the company’s 35-county service area. More than 53 miles of overhead lines have been installed underground.”
South Dakota has also begun this transition. The work was made possible through a federal grant after a major storm in the late 1990s. Since then, storms have not had the same devastating impact on the power grid of the areas served.
Similar projects are occurring overseas, for example in Germany, Singapore, and The Netherlands.
But the main barriers are cost and complexity. EEI polling found that most customers are willing to pay a modest premium (10-20%) to cover costs, but not the 100% premium that would be more realistic. The Motley Fool estimates that burying power lines costs over ten times more ($750/foot vs. $70/foot). The process is also lengthy: North Carolina determined that burying its utilities would be a 25-year project.
Another issue is that when underground lines do get damaged, they’re more expensive to repair than overhead ones. This can happen from floods and earthquakes, and the infrastructure feeding underground lines is still above-ground. It’s also a more difficult prospect in urban areas since it requires disrupting existing infrastructure.
But power line maintenance has its own costs. After Hurricane Sandy, New Jersey’s power provider spent $250-300 million to repair lines. Following Hurricane Ida, Louisiana power providers spent over $4 billion fixing the damage, asking for $1 billion in government loans to cover the cost. And of course, the knocked-out households must foot the costs of using generators and missing work.
A more incremental solution than burying lines is to use technology that enhances above-grade ones. This includes having stronger utility poles and wires; using drones to spot damage, and deploying smart grids that help reroute energy away from vulnerable substations.
Perhaps the ultimate efficiency gain would be more compact development, since that requires less line extension and enables individual units to serve more heads. Instead, the system we have is for governments to subsidize large, monopolistic public or private utilities, who then must fulfill remote coverage goals. Under this model, the U.S. will continue to have over-extended energy systems, and it will be impossible to achieve true resilience—meaning millions of people will continue losing power during rough weather.
This article featured additional reporting from Market Urbanism Report content staffer Ethan Finlan.