Project turns state roadways into a renewable energy source

By University of Illinois at Urbana-Champaign, Illinois Sustainable Technology Center | August 16, 2017

The Illinois Department of Transportation has approved implementation of a renewable energy demonstration project using grasses collected from mowing highway rights-of-way (ROW).

The work will implement the findings of a three-year study by a multi-disciplinary team including the Illinois Sustainable Technology Center at the Prairie Research Institute of the University of Illinois. The team concluded that nearly $2 million in energy could be recouped by harvesting the biofuel for energy. They also calculated that this would not only offset the cost of mowing, but also generate net revenue.

The fourth year of the project will implement the production on a 10-plus acre parcel in Madison County, in addition to the original test plot in Rantoul, Illinois. The operation will produce standard operating procedures and a strategic plan to scale up production elsewhere in the state. The implementation plan also emphasizes including native pollinators and nectar plants on highway rights-of-way, areas which can serve as wildlife corridors for native species.

A video on the multiple science disciplines behind the project is now available.

The biomass will be used to provide heat at IDOT transportation garages and also the U of I Energy Farm’s new biomass boiler, which is part of the low-carbon energy strategy developed in the university’s Illinois Climate Action Plan (iCAP).

ISTC scientists have already pelletized bio-mass from three native species – "Kanlow" switchgrass, IL-ecotype big bluestem, and "Rumsey" Indiangrass – and have demonstrated satisfactory combustion characteristics in commercially available stoves. 

As the project scales up, ISTC will conduct dry runs spanning collection, sizing and conversion of the material to pellets or briquettes. They will give special attention to handling and production issues necessary for co-combustion in coal power plants. The project has also examined the biomass as a fuel to possibly heat IDOT garage facilities near the harvesting plots.

The U of I's Integrated Bioprocessing Research Laboratory will also investigate producing liquid fuels from the mixed species using hydrolysis, fermentation, and gasification technologies, according to principal investigator Hans-Peter Blaschek.

Measurements of energy content by the team also showed that one metric ton of cordgrass, for instance, can yield 77.11 gallons of ethanol or approximately 33 gallons of biodiesel precursors, according to B.K. Sharma, senior research engineer at ISTC. 

The team includes specialists in agronomy, chemistry, genetics, environmental engineering, and logistics from ISTC, the College of Agricultural Consumer and Environmental Sciences (Crop Sciences, Food Science and Human Nutrition), the College of Engineering, and the U of I Extension. The Chicago company Lanzatech is a private partner in the production of liquid fuels.

The Madison County research plot is at the junction of Illinois 255 and Wagon Wheel Road in Edwardsville, Illinois. It is part of more than 100,000 acres of public property that are important to highway safety but otherwise must be maintained at the taxpayers' expense. 

The Illinois Department of Transportation is sponsoring the research as part of their Transforming Transportation for Tomorrow vision which includes "the development of innovative solutions to increase sustainability within the infrastructure system and to share a commitment to environmental stewardship and innovation."