Potentiality of Agricultural Residues from Pruning Fruit Trees for Energy Source in Northern Thailand

The objective of this research is to investigate the availability and fuel properties of pruning wood from fruit trees as a source of alternative energy production for thermal biomass power plants. The study areas were in four districts of Lampang Province, Northern Thailand. Two different common fruit varieties, such as longan and mango, were selected for data collection. Total planted areas of longan and mango were 3809 ha (longan 3104 ha and mango 705 ha). A field survey was conducted to display the overall data of the study areas, with total areas of longan 196 ha and mango 44 ha. Pruning wood samples were collected directly after fruit harvesting, and the wood samples were then transformed into woodchips. Woodchip samples were taken for property analysis. The results showed that the weight of pruning wood was 36.48 and 26.43 kg/tree in longan and mango, respectively. The availability of fresh pruned wood was 20,571 t/year and 12,525 t/year for dried woodchip. The lower heating values of dried woodchip varied from 17.8 MJ/kg in mango to 18.0 MJ/kg in longan. Then, the minimum installed capacity of the thermal biomass power plant was approximately 2 MW.