Helping the Grid Keep Pace with a Power-Hungry Economy
This would complicate a project that, for instance, seeks to build new lines to move a lot of wind electricity from the windy Great Plains states to the highly populated Eastern Seaboard, she said.
“Think of all of the states that have to sign off for an approval … ,” said Tierney. “That’s a really tough thing, because all of the in-between states aren’t so keen on paying for it and [having] new lines.”
Lack of public acceptance can also be a barrier to expanding power transmission, added Wändi Bruine de Bruin, Provost Professor of Public Policy, Psychology, and Behavioral Science at the University of Southern California.
“People often don’t like it,” she said. “These negative public perceptions can turn into public opposition, which may then prevent new energy infrastructure from being implemented.”
It’s overly simplistic to dismiss this as a NIMBY (‘not in my backyard’) reaction, said Bruine de Bruin. “People have real concerns about energy infrastructure that we have to take seriously and work hard to address.”
For example, one common concern is about property values, she said. When new high-voltage lines were being proposed in New Hampshire, a participant at a public meeting commented: “How can they not take into account the dramatic decline in property values for all the neighbors of these lines? People who want to move from living next to tall power lines won’t be able to sell their houses; for most of us, that’s our primary investment.”
The research evidence on this issue is mixed, noted Bruine de Bruin. There is some evidence of areas where property values have gone down, and some places where property values are unchanged or even go up. It may depend partly on whether the lines change what the area looks like, and also whether having new power lines brings benefits to the area, she said.
Victor also stressed the importance of creating benefits for residents. “One of the most important things we have to do is move away from NIMBY to incentive systems that are ‘YIMBY’ or ‘yes in my backyard’ — creating direct benefits that flow to folks who host projects or who are near projects,” he said. “Because then they don’t see projects all as negative, but instead see them as positive.”
New Technologies to Bolster Existing Infrastructure
Novel technologies could make it easier to increase transmission capacity with fewer bureaucratic and political hurdles, other speakers explained.
Duncan Callaway, professor and chair of the Energy and Resources Group at the University of California, Berkeley, described a newer kind of conductor that could enable more electricity to travel through existing power lines.
Right now, most of the U.S. grid uses aluminum conductors reinforced with a steel center. Replacing the steel centers with composite-based cores that do not expand and sag when the current becomes large would allow higher operating temperatures and a higher maximum amount of electrical current, said Callaway. He noted that this technology has been used for decades on long-distance spans like river crossings.
“Reconductoring” in this way could double the capacity of an existing transmission corridor, Callaway’s research team found, and without the need to build new towers or secure rights-of-way on new land. The approach has cost advantages too, he said: “Taking all of the data together, it’s about twice as expensive to build new transmission capacity with new right-of-way than just to do reconductoring.”
Liza Reed, director for climate and energy at the Niskanen Center, spoke about the potential of another technology — high-voltage direct current (HVDC), which she called “an old technology with a new twist.” Her research looked at the possibility of converting ACDC transmission corridors to HVDC, which has 3.5 times the transmission capacity for the same right-of-way.
HVDC has other benefits too, including greater resilience and a far smaller footprint on the land at the AC to DC conversion stations than legacy ACDC systems, said Reed. HVDC also can be sited below ground much more easily than ACDC, making it easier to co-locate along railways and highways.
New approaches to building infrastructure also matter, explained Larry Bekkedahl, senior vice president at Portland General Electric. He described the novel use of hydraulics to lift the top half of transmission towers to enable reconductoring or converting from AC to DC. A different company is using 10-foot diameter plasma boring as a potentially more cost-effective way to put lines underground. “We’ve got to think differently about how we install,” Bekkedahl said.
Victor expressed hope that new technologies could yield more progress. “Changes in technology could change the political environment around the hard problem of building new transmission,” he said. “It allows you to move more power with existing rights-of-way … and that lowers the political barriers.”
Sara Frueh is Senior Writer at the National Academies of Sciences, Engineering, and Medicine. The article was originally posted to the website of the National Academies.
