One of the biggest obstacles to the expansion of clean energy in the United States is the lack of power lines. New transmission lines can take a decade or more to build due to permitting delays and local backlash. But there may be a faster, cheaper solution, according to two reports published Tuesday.
Replacing existing power lines with cables made of state-of-the-art materials could roughly double the capacity of the power grid in many areas of the country, making room for much more wind and solar power.
This technique, known as “advanced reducibility”, is widely used in other countries. But many U.S. utilities have been slow to adopt it because of unfamiliarity with the technology as well as regulatory and bureaucratic hurdles, researchers found.
“We were quite surprised by how much capacity gain you can achieve with reconductivity,” said Amol Phadke, a senior scientist at the University of California, Berkeley, who contributed to one of the reports published Tuesday. Working with GridLab, a consulting firm, researchers from Berkeley looked at what would happen if advanced renewables were widely adopted.
“It’s not the only thing we need to do to upgrade the network, but it can be an important part of the solution,” Dr Phadke said.
Today, most power cables are made 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 that could hold more aluminum. These advanced cables can carry up to twice the current of older models.
Replacing old lines can be done relatively quickly. In 2011, AEP, a utility company in Texas, urgently needed to deliver more power to the Lower Rio Grande Valley to cope with increasing population growth. It would take a long time to acquire land and permits and build towers for a new transmission line. Instead, AEP replaced 240 miles of cables on an existing line with advanced conductors, which took less than three years and increased the lines’ carrying capacity by 40 percent.
In many places, 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 pipelines on a national scale—replacing thousands of miles of wire—they could add four times as much transmission capacity by 2035 as they are currently on pace for.
This would allow far more solar and wind power to be used than the thousands of projects that have been proposed but cannot go ahead because local grids are too clogged to accommodate them.
Installing advanced pipelines is a promising idea, but questions remain, such as how much additional wind and solar power can be built near existing lines, said Shinjini Menon, vice president of asset management and fire safety at Southern California Edison, one of its largest country. public utility services. Power companies will likely still have to build a lot of new lines to reach more remote windy and sunny areas, he said.
“We agree that advanced pipelines are going to be very, very useful,” said Ms. Menon, whose company has already started several pipeline projects in California. “But how far can we take it? The jury is still out.”
Experts generally agree that the slow development of the electric grid is the Achilles heel of the transition to cleaner energy. The Energy Department estimates that the nation’s transmission line network may need to be expanded by two-thirds or more by 2035 to meet President Biden’s goals of supplying the nation with clean energy.
But building transmission lines has become a brutal slog, and it can take a decade or more for developers to lay a new line across multiple counties, get permits from a patchwork of different agencies and face lawsuits over altered views or damage to ecosystems. Last year, the United States added just 251 miles of high-voltage transmission lines, a number that has been declining for a decade.
The stakes for the climate are high. In 2022, Congress approved hundreds of billions of dollars for solar panels, wind turbines, electric vehicles and other non-polluting technologies to combat global warming as part of the Inflation Reduction Act. But if the United States can’t add new transmission capacity more quickly, about half of the emissions reductions expected from that law may not materialize, researchers at Princeton’s REPEAT Program found.
The difficulty of building new lines has led many energy experts and industry executives to explore ways to squeeze more from the existing grid. This 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 ease congestion on the grid. Studies have found that these techniques can increase network capacity by 10 to 30 percent at low cost.
Countries like Belgium and the Netherlands have widely deployed advanced pipelines to incorporate more wind and solar power, said Emilia Chojkiewicz, one of the authors of the Berkeley report.
“We spoke to the transmission system designers there and they all said this is not unreasonable,” Ms Chojkiewicz said. “It’s often difficult to get new rights-of-way for the lines, and the rollback is much quicker.”
If reducibility is so effective, why aren’t more businesses in the United States doing it? That question was the focus of the 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. This means that new technologies — which require careful study and retraining of workers — sometimes spread more slowly than in countries with few network operators.
“A lot of utilities are risk averse,” said Dave Bryant, the chief technology officer for CTC Global, a leading manufacturer of advanced pipelines with projects in more than 60 countries.
There are also mismatched incentives, according to the report. Because of the way utilities are compensated, they often have more financial incentive to build new lines than to upgrade existing equipment. Conversely, some regulators are wary of the higher upfront cost of advanced pipelines — even if they pay for themselves in the long run. Many utilities also have little incentive to cooperate with each other in long-term transmission planning.
“The biggest obstacle is that the industry and regulators are still in a short-term, reactive mindset,” said Casey Baker, senior program manager at GridLab. “But now we’re in an era where we need the network to grow very quickly, and our existing processes haven’t kept up with that reality.”
That may be starting to change in some places. In Montana, Northwestern Energy recently replaced part of an aging line with advanced conductors to reduce fire risk—the new line deteriorated less in the heat, making it less likely to come into contact with trees. Pleased with the results, Montana lawmakers passed a bill that would give utilities financial incentives to install advanced pipelines. A bill in Virginia would require utilities to consider the technology.
With electricity demand starting to rise for the first time in two decades, with new data centers, factories and electric vehicles creating grid bottlenecks, many utilities are overcoming their wariness of new technologies.
“We’re seeing a lot more interest in grid enhancement technologies, whether it’s reductions or other options,” said Pedro Pizarro, president and CEO of Edison International, a California power company, and president of the Edison Electric Institute. , a commercial utility. “There is a sense of urgency.”
