One of the biggest obstacles to the expansion of clean energy in the United States is the lack of power lines. Building new transmission lines can take a decade or more, allowing for delays and local opposition. But there may be a faster, cheaper solution, according to two reports released on Tuesday.
Replacing existing power lines with cables made of innovative materials could roughly double the capacity of the electric grid in many parts of the country, making room for more wind and solar power.
This technique, known as “advanced reconductoring,” is widely used in other countries. But many US utilities have been slow to adopt it because of their unfamiliarity with the technology as well as regulatory and bureaucratic hurdles, the researchers found.
“We were quite amazed at how much capacity increase you can get by reconductoring,” said Amol Phadke, a senior scientist at the University of California, Berkeley, who contributed to one of the reports released in Tuesday. In collaboration with GridLab, a consulting firm, researchers from Berkeley looked at what would happen if advanced reconductoring were widely adopted.
“This is not the only thing we need to do to upgrade the grid, but it can be a major part of the solution,” said Dr. Phadke.
Today, most power lines consist of steel cores surrounded by aluminum strands, a design that has been around for a century. In the 2000s, several companies developed cables that used smaller, lighter cores such as carbon fiber and could contain more aluminum. These advanced cables can carry up to twice as much current as older models.
Replacing old lines can be done relatively quickly. In 2011, AEP, a utility in Texas, urgently needed to deliver more power to the Lower Rio Grande Valley to meet the increasing population growth. Acquiring land and permits and building towers for a new transmission line took too long. Instead, the AEP replaced 240 miles of wires on an existing line with advanced conductors, which took less than three years and increased the carrying capacity of the lines by 40 percent.
In many areas, upgrading power lines with advanced conductors could nearly double the capacity of existing transmission corridors at less than half the cost of building new lines, researchers have found. If utilities began deploying advanced conductors on a national scale — replacing thousands of miles of wires — they could add four times as much transmission capacity by 2035 as they are currently at speed. to do.
That would allow the use of more solar and wind power from the thousands of projects that have been proposed but cannot move forward because local grids are too clogged to accommodate them.
Installing advanced conductors is a good idea, but questions remain, including how much additional wind and solar power can be built near existing lines, said Shinjini Menon, vice president of asset management. and wildfire safety at Southern California Edison, one of the nation’s largest. Things. Power companies will likely still need to build many new lines to reach more distant windy and sunny areas, he said.
“We agree that advanced conductors are going to be very, very useful,” Ms. Menon, whose company has already embarked on several reconductoring projects in California. “But how far can we take it? The jury is still out.”
Experts widely agree that the sluggish build-out of the electric grid is the Achilles’ heel of the transition to cleaner energy. The Department of Energy estimates that the nation’s network of transmission lines may need to expand by two-thirds or more by 2035 to meet President Biden’s goals of powering the nation with clean energy.
But building transmission lines has been a brutal slog, and it can take a decade or more for developers to lay a new line in multiple counties, get permission from a patchwork of different other agencies and address lawsuits regarding damaged views or damage to ecosystems. Last year, the United States only added 251 miles of high-voltage transmission linesa number that has been declining for a decade.
The climate stakes are high. In 2022, Congress approved hundreds of billions of dollars for solar panels, wind turbines, electric vehicles and other non-polluting technologies to tackle global warming as part of the Inflation Reduction Act. But if the United States can’t add new transmission capacity faster, about half of the emissions reductions expected from that law may not be trueresearchers in the Princeton-led REPEAT Project found.
The difficulty of building new lines has led many energy experts and industry officials to explore ways to further disrupt the current grid. That includes “grid enhancing technologies” such as sensors that allow utilities to send more power through existing lines without overloading them and advanced controls that allow operators to reduce grid congestion. Studies have found that these techniques can increase grid capacity by 10 to 30 percent at low cost.
Countries like Belgium and the Netherlands have widely deployed advanced conductors to combine more wind and solar power, said Emilia Chojkiewicz, one of the authors of the Berkeley report.
“We talked to the delivery system planners there and they all said it was a no-brainer,” Ms. Chojkiewicz. “It’s often difficult to get new rights of way for lines, and the reconductor is faster.”
If reconductoring is so effective, why aren’t more utilities in the United States doing it? That question is the focus of a second report released Tuesday, by GridLab and Energy Innovation, a nonprofit organization.
One problem is the fragmented nature of America’s electricity system, which is actually three grids operated by 3,200 different utilities and a complex patchwork of regional planners and regulators. That means new technologies — which require careful learning and retraining of workers — sometimes spread more slowly than in countries with fewer grid operators.
“Many utilities are risk averse,” says Dave Bryant, the chief technology officer for CTC Global, a leading manufacturer of advanced conductors with projects in more than 60 countries.
There are also mismatched incentives, the report found. Because of the way utilities are paid, they often have a greater financial incentive to build new lines rather than upgrade existing equipment. Conversely, some regulators are wary of the higher initial cost of advanced conductors – even if they pay for themselves in the long run. Many utilities also have little motivation to cooperate with each other in long-term transmission planning.
“The biggest obstacle is that the industry and regulators are still caught up in a short-term, reactive mind-set,” said Casey Baker, a senior program manager at GridLab. “But now we’re in an era where we need the grid to grow very quickly, and our existing processes haven’t caught up to that fact.”
This may be starting to change in some areas. In Montana, Northwestern Energy recently replaced part of an aging line with advanced conductors to reduce fire risk — the new line sizzles in the heat, making it more likely to come into contact with trees. Pleased with the results, Montana lawmakers passed the bill which would provide financial incentives to utilities to install advanced conductors. A Virginia bill equipment will be required to consider technology.
As electricity demand begins to increase for the first time in two decades due to new data centers, factories and electric vehicles, creating bottlenecks on the grid, many utilities are reeling from their concerns about new technology.
“We’re seeing more interest in technologies that improve the grid, whether it’s reconductoring or other options,” said Pedro Pizarro, the president and chief executive of Edison International, a California power company, and the chairman of the Edison Electric Institute, a utility trade organization. “There is a sense of urgency.”
