Mapping clean energy on the highway

In the nearly 70 years since the Federal Aid Highway Act ushered in the age of the automobile, Americans have perpetually lengthened, expanded and fortified our network of interstates and freeways. We now urgently need to do the same with our electric grid.

As it turns out, the very same lanes that have fueled our car culture, and carbon emissions, could ultimately play a vital role powering our national grid with clean energy.

All along the vast lengths of federal and state highways across the United States, lies a bounty of public land — our unassuming rights-of-way (ROWs). It’s where the infrastructure for our clean energy future, including solar panels and high-voltage transmission lines, can grow. Already designated as public land, there are no lengthy environmental reviews, no need for eminent domain and no patchwork of owner approvals to wade through. Community outrage will likely be muted if it forms at all.

This is land we glimpse as we cruise by, barely giving it another thought. Why not put these buffers of land to more productive use?

That’s exactly what our organizations did in Georgia, where we installed a solar array along 18 miles of Interstate 85. We also have pilot projects being built along highways in Maryland, Pennsylvania, Maine, Wisconsin, Minnesota and Florida. We are constantly examining innovations that could make the most of our roadways, and in the distant future that could even include small-scale wind turbine technology producing energy from the airflow cars create as they zoom past.

Being able to use the land around highways as a place to both generate and move energy is a recent development. Only in 2021 did state departments of transportation receive the formal go-ahead from the Federal Highway Administration to pursue innovative land uses alongside state and federal highways, including renewable energy production and clean energy transmission and distribution.

In 2022, the White House included “repurposing transportation rights-of-way” among several cross-cutting innovations that could help us meet our 2050 climate goals.

That same year, we developed a way to precisely pinpoint the right rights-of-way based on slope, solar energy capturing capacity, proximity to existing transmission lines and more, as well as the best places to route vital transmission lines. Our organizations worked together to create two interactive mapping tools developers and state transportation departments can use to home in on locations for possible solar arrays and transmission lines.

Now, highway solar and transmission may be getting a boost. This past May, the Federal Energy Regulatory Commission (FERC), the agency that regulates interstate electricity transmission, issued a new rule requiring grid operators to anticipate needed growth 20 years in advance. The rule also requires states and grid customers to share the costs of new transmission projects rather than expecting renewable energy developers to cover the bill.

Growing the grid using land along highways owned and managed by states is a great opportunity. Minnesota sees the potential. The state recently approved the ability to install high-voltage transmission lines along its highways, a move we hope inspires other states, particularly those that currently ban the practice of putting high-voltage lines along highways.

These states are concerned the lines would restrict their ability to expand the road in the future and pose a possible crash-risk for drivers. Mitigation efforts, including buried transmission lines and informed planning using software like Esri’s right-of-way transmission mapping tool to prioritize setting transmission lines back from the highway and to plan for future expansions, diminish many of these concerns.

The need for more energy and transmission is acute.

We could have as many as 42 million electric vehicles on U.S. roads by 2030, along with wider use of heat pumps and electric appliances and expanding artificial intelligence technology. We will need clean energy to power it all.

Meanwhile, more than 2 terawatts worth of wind and solar energy and battery storage projects are waiting to connect to transmission lines, according to the U.S. Energy Department. There simply hasn’t been the grid capacity to take on many promising renewable energy projects.

It won’t matter how many wind turbines are erected or solar panels are positioned if we don’t have an electric grid with more capacity to absorb the power being generated to fuel our clean energy cars, homes and businesses.

The quickest and most efficient way to update the energy grid is by using what we already have — the unused public land on the sides of federal and state highways that rarely receives more than a glance.