Harvest storage and handling of round and square bales of giant reed and switchgrass, an economic and technical evaluation

This study evaluated an innovative collection system for biomass based on single-pass harvesting to reduce handling and storage costs. Trials were conducted on two herbaceous perennials: giant reed (Arundo donax L.) and switchgrass (Panicum virgatum L.). A technical and economic evaluation compared two single-pass harvesting systems in which the biomass was cut-shredded-baled in the same operation. The two systems were composed of a Nobili biotriturator (for biomass shredding and windrowing) front-mounted on a 4-wheel-drive tractor and two types of balers: a KUHN VB2160 round baler and a KUHN LSB 1290 large square baler. Costs of harvesting, handling, storage and delivery to the conversion plant were evaluated. Three distances of delivering were considered (0–20; 20–40; 40–60 km). It was estimated that the harvesting system could produce round bales of switchgrass and giant reed stored in-field under a plastic tarp at a cost of 22.3 € Mg−1 and 23.3 € Mg−1 dry and square bales at 26.0 € Mg−1 and 21.7 € Mg−1 for switchgrass and giant reed respectively. The costs of harvesting, handling, in-field storage and delivery to the conversion plant amounted to 43.7 € Mg−1 and 45.7 € Mg−1 dry for round bales and 43.1 € Mg−1 dry and 34.9 € Mg−1 for square bales of switchgrass and giant reed for delivery distances of less than 20 km.