The PROGRASS® idea

PROGRASS® focuses on the semi-natural grasslands of the central-European riparian zones and roadside verges. Only a fraction of the grass growing in these areas can be used in animal feeding.

For the protection of wildlife, the ecologically most valuable areas can be mowed only late in the year. Due to the late mowing, the green cut is less suitable for animal feeding or for use in biogas plants. However, a further decrease of agricultural activities could threaten the open character of many central-European grasslands and would favour a conversion to scrublands.

Extensive Cultivation

PROGRASS® aims to conserve the semi-natural character of the central European grasslands by converting the green cut into a profitable energy resource which will stimulate further extensive cultivation of the areas by local farmers.

Usually, the biomass obtained by harvesting extensively used grasslands late in the year contains a large fraction of fibrous and ligneous materials. Such kind of biomass is less suitable for animal feeding. Utilization in biogas plants is inefficient since the material is only poorly digestible and the gas yield would be low. It is also less suited for combustion due to the high ash and nitrogen contents.

These problems can be solved by the innovative IFBB technology (integrated generation of solid fuel and biogas from biomass) which is the heart of the PROGRASS® approach to utilize biomass from semi-natural grasslands for distributed energy production. In principle, it is also possible to transfer this approach to other grassed areas (for example grass verges on roadsides).

Basic prerequisites

for the distributed production of bio-energy by the PROGRASS® approach are:

• Availability, harvest yields of river beds and other grassland sites
• Harvesting feasibility of grassland sites (technical and meteorological requirements, accessibility of sites)
• Site location in relation to the bio-energy plant, affecting transportation costs
• …

• Involvement of stakeholders (farmers etc.) in the implementation process
• Innovative capacity of the local agricultural community
• Limited market for mature grass as animal feed
• Availability of nearby pellet burning furnaces, demand for grass pellets as solid fuel
• Subsidies for grassland management and production of bio-energy
• Willingness of farmers to carry risks and to invest

harvesting biomass

processed biomass

"I took over the project from Dr. Konrad Scheffer, in a process of very straight forward discussion. Of course it was in my interest, that the results of his work wouldn't disappear with his retirement."

Dr. Michael Wachendorf

"I realised that this technique would also be suitable for grasslands. But by then he already had me. 'Couldn't that work on your grasslands?' he asked me. And I replied, if the grassland persists it functions in nature preservation, we may harvest the biomass very late in the year. But it would contain so much fiber, I don't think it will work. And he said, 'yes, but we could try!'

That was the moment, when I was hooked."