What was disposed of as worthless grass cuttings for years is given a second life in South Holland. Every year, around ten thousand tons of grass are mowed along provincial roads in the province. Until recently, most of it ended up on the compost heap. That is now changing thanks to a broad partnership under the name Greenhub Zuid-Holland.
Greenhub Zuid-Holland consists of more than thirty partners, including municipalities, water boards, contractors and technological parties. They work together on circular applications for roadside grass. The applications are surprisingly diverse. For example, the grass is processed into building panels, paper and soil improvers.
In a pilot in Leiden, garage boxes were clad with panels made of pressed roadside grass. The fibreboards proved to be just as strong as wood. In the provincial government building, even furniture tops were incorporated in which charred roadside grass was used as a pigment. It shows that the applications can be not only functional, but also aesthetically attractive.
Roadside grass also proves useful in the paper industry. Part of the grass is processed into paper that is used for promotional material of the province. This converts a local residual flow into a visible product with communication power.
A third application focuses on agriculture. By drying and heating the grass without oxygen, biochar is created. This carbon-rich substance retains moisture in dry soils and restores soil quality. According to the parties involved, each ton of roadside grass stores approximately twenty-four kilos of carbon in the soil. In addition, a successful trial was carried out on Goeree Overflakkee, where two thousand tons of grass were processed into Bokashi. According to farmers, this fermented soil improver led to more soil life and an increase in insects and birds on the land.
Data and scale
To organize the process, a digital platform has been developed that provides insight into the ownership of verges, the mowing times and the processing possibilities. This platform attempts to make the logistic puzzle of verge management and raw material processing clear.
The ambition is great. Where one hundred and twenty tons of roadside grass is currently processed annually, this must grow to thirty thousand tons in the future. This increase in scale is necessary to contribute to the national objectives for biobased construction. In 2030, thirty percent of new homes must consist of at least thirty percent renewable raw materials. Roadside grass can play a significant role in this.
Local initiative with broad impact
The initiative shows that a local residual flow, if well organised, can grow into a valuable link in the circular economy. Economically, it provides cost savings and new revenue models. For the environment, it means less emissions and better soil management. And socially, it ensures cooperation between parties that previously rarely encountered each other.
South Holland offers an example that deserves to be followed. From verge to building material, the grass along the road turns out to be worth much more than expected.
<strong> More info: </strong> Greenhub-Zuidholland.nl
