Italian experiences on Arundo harvesting: Economic and energy appraisal

Abstract

Giant reed (Arundo donax L.) is recognised as a promising energy crop. While many studies have been conducted on agronomic practices, specific researches on cost-effectiveness and energy demand of the harvesting phase are limited. In the present work, four different harvesting systems, already evaluated from a technical point of view, were considered: system 1, self-propelled forage harvester (SFPH) on low-yielding cultivation; system 2, mower plus SFPH; system 3, SFPH on high-yielding cultivation; system 4, shredder plus round-baler. Systems 1 and 2 were tested on a 1-year-old cultivation; systems 3 and 4 on a 3- and 4-year-old, respectively. The study was aimed at identifying the main factors affecting the economic and energy cost of harvesting. Crop condition, age of plantation, and yield had a key role in determining the field efficiency of the machine and, in turn, the extent of harvesting cost. The lower field efficiency of the SPFH when harvesting older and unevenly arranged plants (system 3) required a higher economic and energy cost. System 4 (shredding plus baling) showed the lowest economic cost (112.90 € h-1), while system 1 was the most energy-saving (4.46 GJ ha-1).