Sound barriers and snow fences along highways have the potential to provide clean energy in Minnesota.

A newly funded MnDOT study, Harnessing Solar Energy through Noise Barriers and Structural Snow Fencing, is investigating how to utilize existing noise barriers and snow fences on Minnesota highways to harvest clean, cost-effective energy.

“Snow fences and noise walls are structural barriers with a singular purpose. Snow fences are intended to limit snow from drifting onto our highways and noise walls are intended to reduce noise to a comfortable level for communities living near our highways. Finding a way to integrate solar that maintains their structural integrity could transform the use of these barriers from single purpose to multi-purpose,” says Dan Gullickson, MnDOT’s Blowing Snow Control Shared Services Program Supervisor, who is overseeing the research project.

Solar energy is energy captured from the sun and converted into thermal or electrical energy. It is a clean and abundant renewable energy source and generally requires very little maintenance after installation. Solar energy has a variety of uses, including providing electricity to power street lamps and homes, heating and cooling spaces, and heating water.

“We’ve seen some applications of solar panels on noise walls—primarily in European countries—but the addition of solar panels to snow fences is an entirely new concept,” says Gullickson.

The innovative nature of this project brings many unknowns that MnDOT hopes to answer, such as: Is it possible to engineer these structures without disrupting their functionality? What safety measures need to be taken to ensure the public and MnDOT workers stay safe if they come into contact with the panels? What are the lifecycle costs of installing and maintaining solar? How much energy could they generate and how does that connect with existing power grids?

One estimate shows that a thousand miles of solar panels could power all the street lights along Minnesota highways or 43,333 residential homes. (Assuming each solar panel is 330W and 1,000 panels could generate up to 330kW per mile.)

“We know Minnesota and North Dakota winters bring a lot of snow—which is disruptive to our travelers and farmers. We hope to create a sustainable solution that aids drivers and farmers, but also harnessing energy which would be able to offset the cost of construction and installation,” says Mijia Yang from North Dakota State University, the lead researcher.

Gullickson and a diverse team of MnDOT experts – from the field of environmental stewardship to traffic engineering – will guide the research and review findings.

The study will include surveys, lab testing or modeling of possible design options and a cost-benefit analysis—planned to be completed by of June 2021.

Currently, the research team is developing surveys to better understand public opinion on solar energy (including energy prices and solar panel infrastructure), power companies’ interest in purchasing solar energy generated through the right-of-way and legal considerations for harvesting solar energy through the rights-of-way.

 “Surveying the public and utility providers may uncover questions that we hadn’t previously anticipated. We hope to address those hurdles throughout the study,” says Gullickson. Follow along for project updates on MnDOT’s Office of Research & Innovation website.