Local Energy Use of Biomass from Apple Orchards-An LCA Study

Generation of heat in small and medium-size energy systems using local sources of energy is one of the best solutions for sustainable regional development, from an economic, environmental, and social point of view. Depending on the local circumstances and preferences of the agricultural activity, different types and potentials of biomass are available for energy recovery. Poland is the third-largest producer of apples in the world. The large cumulative area of apple orchards in Poland and necessity of regular tree pruning creates a significant potential for agricultural biomass residues. In this paper, the LCA analysis of a new and integrated process chain focused on the conversion of cut branches coming from apple orchards into heat is conducted. Furthermore, the obtained results of the environmental indices have been compared to traditional mulching of pruned biomass in the orchard. It was shown that in terms of the LCA analysis, the biomass harvesting, baling, and transportation to the local heat producer leads to an overall environmental gain. The cumulative Climate Change Potential for pruning to energy scenario was 92.0 kg CO2 equivalent center dot ha(-1). At the same time, the mulching and leaving of the pruned biomass in the orchard (pruning to soil scenario) was associated with a CO2 equivalent of 1690 kg center dot ha(-1), although the soil effect itself amounted to -5.9 kg CO2 eq.center dot ha(-1). Moreover, the sensitivity analysis of the LCA showed that in the case of the PtE chain, the transportation distance of the pruned bales should be limited to a local range to maintain the positive environmental and energy effects.