We Need New Transmission. Why Can’t We Build It?

We Need New Transmission. Why Can’t We Build It?

Our electricity transmission system is old, and it shows. The average age of its physical infrastructure is 40 years, but in some locations, it’s more than a century. One notorious example was on Northern California’s Caribou-Palermo line in 2018, when a hook, manufactured in 1924, failed and dropped an energized power line to the forest floor. It ignited the monstrous “Camp Fire” that charred 153,000 acres, destroyed the town of Paradise, and leveled 14,000 homes. 

Last summer, President Biden signed the Inflation Reduction Act (IRA), which was a climate investment bill designed to fund and incentivize building clean-energy infrastructure and create hundreds of thousands of new, well-paying jobs. His administration has set the goal to have 100% clean electricity by 2035, to combat global warming and associated climate change. That calls for much more transmission planning, as the percentage of clean energy resources on the grid increases significantly. But it also means that we’ll need more total transmission capacity.

Capacity in interconnection queues as of the end of 2022 totaling over 1.3 gigawatts. Source

At the same time, the way new generation is added to the grid isn’t working very well. U.S. Department of Energy estimated in the Fall of 2022 that there are 1.4 terawatts of new generation projects stalled in various interconnection queues across the country, the vast majority being renewable projects vital to meeting the 2035 clean electricity goal. 

Unfortunately, we’re far behind on the goals stated above, and that’s a problem because our existing transmission system is not just aging; it often lacks the capacity needed even now, because of constraints—locations on the system where conductors (power lines) reach their rated limits. This creates the need to reroute grid power flows, including calling up more expensive and/or more polluting generation to meet the load in specific locations. It has a financial cost, too: Lawrence Berkeley Laboratory says “In 2022, additional transmission could have reduced electric system costs by more than in any year from 2012 through 2021.”

The U.S. Department of Energy’s National Transmission Needs Study, a draft of which was published just weeks ago, established that our bulk power grid faces four basic needs: increased reliability and resilience; less congestion; more interregional transfer capacity; and more new generation delivery. One of the report’s key findings is that “there is a pressing need for additional electric transmission infrastructure.” About 47,000 GW miles of it, to be precise.

But it's very difficult to build new transmission. First, there are competing interests among many stakeholders: local utilities, regulators, public policymakers, landowners, regional transmission organizations, and communities. Both interstate and intrastate projects involve every utility whose territory they cross, as well as their regulators, requiring the agreement of all, including how costs are apportioned, which means determining who benefits most. Second, these projects require years of planning and coordination, siting, permitting, and acquiring rights-of-way (easements) to build. Some property owners demand hefty sums for easements, or simply refuse, leading to lawsuits and attempts by developers to use eminent domain that can take years. Finally, ratepayers ultimately bear new transmission costs in their monthly electric bills, which regulators must approve, but the public and consumer advocates often oppose. It can take a decade—or more—to complete a project. According to Statista.com, in 2021, fewer than 200 miles of new transmission lines were built in the U.S., with no 500 kV projects completed. 

And it won’t be cheap. A 2022 report sponsored by transmission advocacy group WIRES is quoted in T&D magazine, estimating that $230 to $690 billion in investment in the nation’s transmission system will be needed by 2050, just to meet anticipated “electrification” needs. And a Princeton University study was even more succinct, saying that to achieve a zero-carbon future by 2050, existing transmission capacity will need to expand by about 60% by 2030 and triple through 2050, to connect wind and solar. It also estimates that total capital investment in transmission will need to reach $360 billion by 2030 and $2.4 trillion by 2050.

To support wind and solar generation in E+ scenario with Base siting availability, total transmission capacity more than triples. With curtailments and increased renewable adoption, total transmission needs could increase to over 5x. Source

Fortunately, there are technological solutions in place today that can ease the burden on, and extend both the life and the capacity of, our existing transmission system. One efficient and cost-effective way to do that is by using Grid Enhancing Technologies (GETs), chief among them Dynamic Line Ratings (DLR), which creates the ability to put more electricity through an existing conductor at a fraction of the cost of building new transmission.  The National Transmission Needs study notes that “Advanced transmission technologies are being incorporated on the grid to enhance asset utilization, mitigate curtailments of renewable resources, and better manage congestion patterns. [But] These technologies may not be adequately considered in existing planning processes.”  That last part is concerning given that GETs are truly the only hope we have to get renewables on the grid quickly.

Unfortunately, the current economic model favors building new power lines. And make no mistake, as the DOE report mentions, we need new transmission. But there’s zero chance we build enough of it in time to meet our climate goals. And given the accelerating timetable of the worst effects of climate change encroaching on our world - we must look to implement technology solutions that can create transmission capacity quickly and at low cost. 

Recognizing this fact, nearly two years ago, FERC passed Order 881 which requires that transmission providers use a transmission line rating methodology called Ambient Adjusted Ratings (AAR) to use a more granular set of temperature assessments to determine more accurately how much electricity can be safely transmitted across overhead power lines. That’s a good start. But AAR isn’t nearly as accurate or efficient as DLR. DLR offers real-time field conditions including ambient air temperatures, wind speed, cloud cover, solar heating intensity, precipitation, and line tension or sag. Armed with this information, grid operators can safely go beyond—sometimes well beyond—the limits of traditional “guesstimates,” and even AAR, to maximize grid capacity by some 20-50%.

Beyond Order 881, FERC is also looking at DLR as a means to further promote grid efficiency and a variety of government agencies, like NYSERDA in New York,  are incentivizing utilities to use the technology. In fact, New York State is arguably the leader in the expansion of its grid for renewables and the integration of the technology. National Grid, New York Power Authority, New York State Electric and Gas, and Rochester Gas & Electric are all installing DLR provided by LineVision’s non-contact sensors. 

But if the U.S. is to act in time to save our country from the worst effects of climate change, we must accelerate the use of technology solutions like DLR in the short term as new transmission projects advance through a longer term timeline and process. 

Hilary Pearson

Vice President Policy & External Affairs @ LineVision

This article was orignially posted on Medium