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The global need to transition to renewable and decentralized systems entails agricultural systems as producers of residual biomass. Avocado trees (Persea americana Mill.) are one of the main woody crops cultivated in Mexico, with over 150,000 hectares grown in the country. The aim of the present study is to evaluate the use of avocado pruning residues as an energy input, focusing on the revalorization of biomass and the generation of economic benefits for small producers in the region. For that purpose, we developed allometric equations to calculate biomass availability from pruning residues, evaluated their thermochemical properties, and proposed technological alternatives for their energy use. Two allometric equations for pruning residues as a function of tree height and crown diameter were obtained: one for light and minor maintenance pruning (R2 = 0.63) and one for rejuvenation pruning (R2 = 0.86). From these equations, we estimate the mean amount of biomass generated from light and rejuvenation pruning to be 42.7 and 25.1 kg per tree and year, respectively, which amounts to 1324 and 780 kg ha−1 DM (dry matter), with an energy potential of 26.2 and 15.4 GJ ha−1. The thermochemical analysis shows that a higher proportion of leaves generates a higher ash content, which reduces the quality of the residues as a fuel. Avocado pruning residues have high potential for energy use and could be implemented in the industrial and residential sectors, generating a complementary source of income for producers.

Biomass occupies a very important place among renewable energy sources, and the residual biomass recovery chain represents a sector of fundamental importance. Our work focused on the production of pellets by pruning residues from two of the most important woody crops in Italy: hazelnut and olive groves. We found a higher value of bulk density for the hazelnut pellet (581.30 kg m−3 vs. 562.38 kg m−3) and a higher value of length for the olive pellet (16.66 mm vs. 10.47 mm). The percentages of durability were very similar (98%). The low heating value and ash content of hazelnut and olive were 17.21 MJ kg−1 and 3.1%, and 16.83 MJ kg−1 and 2.5%. A higher concentration of Cu, Pb, and Ni was observed in the hazelnut. The contrary was observed for the concentration of Zn. N content was 0.77% and 1.24% for the hazelnut and the olive, respectively. The concentration of S was 0.00% for both. The quality parameters that do not meet current standards could be improved by mixing these materials with different types of wood.