Plant-based asphalt can reduce emissions from road construction, research shows

It is possible to reduce the emission of harmful substances during the construction of roads by 30 to 60 percent when incorporating plant-based substances into the asphalt mixture, concluded scientists from Wageningen University. This can replace fossil fuel substances, which originate from the remains of prehistoric dead animals and plants. The use of these substances contribute negatively to climate change.

One of the substances in asphalt is bitumen, a component of petroleum, which is used to stick stones together. Wageningen researchers have looked into the possibilities of replacing bitumen with lignin. This is a substance that is found in some trees and plants.

If half of the bitumen in asphalt is replaced by lignin, this could prevent the emission of 85 to 170 million kilograms of carbon dioxide and other substances by the middle of this century in the Netherlands alone. If the bitumen is completely replaced by lignin, this would cut emissions by double the amount.

Globally, lignin in asphalt could reduce harmful emissions by 102 billion kilograms per year. "This development will make a significant contribution to achieving European and global climate goals," the Wageningen researchers said.

A few years ago, a road surface was laid with bio-asphalt in Sas van Gent, Zeeland. Half of the bitumen was replaced by lignin. The first test roads without bitumen should be constructed this year or next year.