Energy loss in different conservation methods of poplar chips

In Italy the production of short rotation forestry (SRF) poplar has started to play a significant role as energy purpose biomas5 and as an alternative plantation for farmers. The climatic conditions of some areas of the Mediterranean basin are particularly suitable to the SRF poplar for energy production. Local weather conditions could also affect the storage of the harvested biomass differently. Power plants need biornass during the whole year, while SRF in Italy is normally harvested between December and March . Long period storage is anyway necessary, at least to have the water content reduced to an acceptable value for combustion. Today the transport cost control pushes towards the production of chips : a test to evaluate the energy-wise behaviour of different chips storage systerns was carried out in Northern Italy. Three piles of poplar chips were bui lt in February 2007, with biomass harvested and chipped using a Claas Jaguar 850, mounting a specific head. The piles rep resented four possible different stocking methods: the first was un ventilated pile, the second pile was fo rmed with simply cumulated material, the third was covered with a special non woven fabrlc, the last one was compacted by a tractor to limit oxygen diffusion into the pile. During the storage period, weather data and temperature inside the pi les were monitored. In 2007 october the piles were opened to col lect chips samples and to study microbial growth zones. Moisture content, ash content, elementary analyses and heating value were measured. The best method is therefore, energy-wise, the non woven fabric covered pi le: of course, the cost of the fabric (anyway re-usable) should be taken in account. The compacted pile showed a good result compared to the uncovered one.