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Minnesota takes rare step to allow power lines alongside highways

A coalition striving to get states to approve high-voltage transmission lines along highways has won a first battle in Minnesota — and wants to expand to other states.
By Jeff St. John

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The Badger-Coulee 345 kV transmission line alongside I-94 between La Crosse and Madison, Wisconsin
The Badger–Coulee 345 kV transmission line alongside Interstate 94 between La Crosse and Madison, Wisconsin (Wisconsin Department of Transportation)

Here are two key facts about transmission lines: The U.S. needs a lot more of them to transition away from fossil fuels; they’re also incredibly difficult to build.

A big part of the challenge is negotiating permits for the power lines — which typically cross hundreds of miles of land — from the numerous jurisdictions and hundreds of private landowners along the planned route. This is a very slow process — too slow at its current pace for the U.S. to build enough power lines to meet its climate goals.

For the past half decade, bipartisan groups have been pushing federal and state lawmakers and transportation agencies to clear the way for a potential shortcut: siting power lines alongside highways.

Last month, Minnesota lawmakers handed them an early victory on this high-voltage highway concept. As part of a bundle of climate laws and policies passed in this year’s legislative session, a provision in an omnibus transportation bill has ended a decade-long prohibition against siting utility infrastructure on the land along state and interstate highways owned and managed by the Minnesota Department of Transportation.

The law opens up all highway rights-of-way for transmission co-location,” said Randy Satterfield, executive director of the NextGen Highways initiative. The nonprofit group has led the advocacy work in the state, including producing a 2022 report demonstrating that power lines along highways are a safe and cost-effective option for the state, and building a coalition of clean energy and labor groups to support the change in the siting law.

Now, NextGen Highway supporters are getting ready for the next steps in their effort: expanding the policy to other states and getting utilities and grid operators in Minnesota to actually make use of the highway transmission routes currently on offer.

NextGen Highways 1.0 is removing the barriers,” said Matthew Prorok, senior policy manager at the nonprofit Great Plains Institute, a founding member of the coalition. NextGen Highways 2.0 is realizing the vision — and to do that you need to incentivize the parties to come together.”

The problem that NextGen Highways is trying to solve

The U.S. needs to double or triple the capacity of its high-voltage transmission grid to make room for the massive amounts of clean energy needed to achieve its climate goals, make the grid more resilient against extreme weather, and serve a growing and increasingly electric-powered economy.

But transmission lines can take more than a decade to site, permit, finance, and build, and many falter in the face of opposition from the hundreds of public and private landowners who can challenge projects crossing their property lines.

Highway rights-of-way provide a neat solution to this challenge, Satterfield said.

State transportation departments, which own and manage both state and interstate highways, are a single entity to negotiate with. And while state agencies manage interstate highways under regulations set by the Federal Highway Administration, the Biden administration issued guidance in 2021 that encourages states to open those rights-of-way for pressing public needs relating to climate change, equitable communications access, and energy reliability.”

It’s hard to say how much transmission could be built if every state allowed it on highway rights-of-way. But this map from NGI Consulting, a consultancy formed in 2020 that’s since been folded into NextGen Highways, indicates how the country’s interstate highways could serve as pathways for the roughly sketched-in interregional high-voltage direct current (HVDC) interconnections that the U.S. Department of Energy’s National Renewable Energy Laboratory has found could enable a significant expansion of U.S. renewable energy capacity.

(NGI Consulting)

But states have been slow to shift from long-standing policies that aim to keep highway rights-of-way clear of other infrastructure that could compromise safety, burden transportation departments with unforeseen costs, or restrict the option of expanding highways in the future. Many states bar utility infrastructure from highway rights-of-way. Those that don’t have been slow to take on the coordination between transportation agencies and utility regulators to make transmission co-location possible.

The key exception to date has been Minnesota’s eastern neighbor, Wisconsin, which passed a law in 2003 that’s enabled utilities to build hundreds of miles of high-voltage overhead power lines and towers along highways. While it’s hard to say whether those lines would have cost more or taken longer without that law, Satterfield noted that an alternative route for the biggest such project undertaken, the Badger–Coulee transmission line built in the Interstates 9094 corridor, would have crossed the property of more than 300 private landowners, setting up the potential for permitting disputes and lawsuits.

Just because transmission lines can be built along highways doesn’t mean that utilities and regional grid planners will pursue the option, of course. That’s where the next stage of work comes in, Satterfield said.

Getting the highways into the grid plans 

In Minnesota, the chief forum for transmission expansions runs through the Midcontinent Independent System Operator (MISO), the grid operator for all or part of 15 U.S. states and Canada’s Manitoba province. MISO is now in the midst of a long-range transmission plan (LRTP) process that represents the single largest regional grid expansion in the country.

The Tranche 1” round of that process concluded in 2022 with a plan for $10.3 billion in transmission projects to be completed later this decade, which MISO predicts will enable 53 gigawatts of clean energy development and provide $37 billion in benefits over the next 20 years.

The next round now being worked out — MISO’s so-called LRTP Tranche 2 — could be two or three times larger than the first and will include some of the region’s first high-capacity 765-kilovolt lines. As part of that continuing planning, MISO has released preliminary maps of the endpoints that it has determined need to be connected by new lines — and NextGen and its partners are looking for potential highway right-of-way routes in Minnesota that match up with those maps, Satterfield said.

MISO doesn’t actually choose the routes of its transmission lines, he emphasized — that’s the purview of state regulators. But we’re looking at those Tranche 2 projects and an overlay of the highway system and other considerations to fixture out where highway corridors make sense.”

Map of MISO Tranche 2.1 transmission projects

MISO has made previous allowances for some of its Tranche 1 projects to run along existing transmission corridors that will add new towers or string higher-voltage power lines. It might not be out of scope to look at highway corridors, now that there’s a law,” he said, and the state of Minnesota has made this a priority.”

Expanding to multiple states

The next important step is finding ways for individual states to coordinate their use of highways that cross their borders, Satterfield said. At least one of the proposed Tranche 2 routes crosses the border of Wisconsin and Minnesota, which both now allow power lines along highways. Xcel Energy, the largest investor-owned utility in Minnesota, is a co-owner of the Badger–Coulee line in Wisconsin, giving it experience with highway right-of-way projects. 

Another of MISO’s planned Tranche 2 routes crosses the Minnesota-Iowa border — and Iowa is the next state on the NextGen Highways agenda.

Last year, Iowa Governor Kim Reynolds (R) issued an executive order instituting a moratorium on administrative rulemaking for all state agencies and requiring them to review existing policies. That order has come under attack by some groups concerned that it could weaken environmental regulations.

But it has also spurred the Iowa Department of Transportation to reach out to NextGen Highways to examine whether its existing rules that determine what utility infrastructure can and can’t be built within state-owned highway rights-of-way might be up for change.

It is our hope that they can see to the point of changing that policy internally, as opposed to going through a legislative route,” Satterfield said.

Other parts of the country are on the NextGen Highways state policy roadmap. The group is working in the states of Washington and Oregon, both of which allow some co-location of transmission in highway rights-of-way, as well as in California, which passed a law last year opening the potential for doing so, Satterfield said. Maine and New Hampshire have passed state laws to encourage transmission along transportation rights-of-way.

Many of the states that NextGen Highways is targeting have aggressive clean energy mandates, including Minnesota. But the Great Plains Institute’s Prorok highlighted that transmission expansion can be a bipartisan policy preference.

The coalition of Minnesota groups backing NextGen Highways includes environmental groups such as Fresh Energy, the Minnesota Center for Environmental Advocacy, Clean Energy Economy Minnesota, and Audubon Minnesota, as well as renewable energy trade group Clean Grid Alliance and labor groups including the Mechanical Contractors Association of America and the Laborers’ International Union of North America Minnesota and North Dakota. It also includes bipartisan advocacy group Citizens’ Climate Lobby and the Minnesota Conservative Energy Forum, which supports transmission for its economic development and domestic energy independence potential.

NextGen Highways is also lobbying for federal legislation that could support state efforts to site transmission along highways. To date, a few of the transmission reform bills proposed in Congress have included language that would incentivize state transportation departments to take on the extra work and cost involved, Satterfield said.

But at present, the odds of bipartisan agreement on energy permitting policy in Congress appear long. State-level wins like the new Minnesota law might be the best path forward for high-voltage highways at the moment.

In the meantime, bipartisan approaches could help bridge gaps between states, Prorok said. If you get states that are neighbors working together, you increase the level of sophistication and engagement.”

Jeff St. John is director of news and special projects at Canary Media. He covers innovative grid technologies, rooftop solar and batteries, clean hydrogen, EV charging and more.