The emerging energetic crisis paves paths for alternative energy sources and also reverts to classical wood fuels augmented by new production technologies. By compressing wood residues, comparably higher combustion heat values, facilitated transportation and warehousing are obtained. Technological processes are different, depending on the final products being either woodchips, pellets, or briquettes. Their energy efficiency is influenced by the quality of densified wood logs (slugs) and the moisture contents, while their applicability features depend on the conditions during apiston-and-mould process. We tested the moisture and temperature dependencies in several laboratory experiments. A mould was constructed and used in a Zwick testing machine. We balanced beech wood saw residues at 9.8 %,11.8 %, 14.8 %, 18 %, and 27.4 % moisture levels and, afterwards, compressed them at temperatures 50 °C, 60 °C, 70 °C, and 80 °C. After the compression completed in about 72 s, we observed intrinsic tensions in the logs during the relaxation phase. We normalised the resulting measurements by the compression and relaxation models. The experiments proved the best quality densified logs with highest compactness were obtained with moistures below 15 % and temperatures above 50 °C.
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