The use of biomass as a source of bioenergy has intensified in recent years and has gained strength in replacing fossil fuels and their derivatives. Jatropha curcas L. oil is currently used as a raw material for the production of biodiesel through the physical extraction of the fruit, generating a large amount of waste. The heterogeneity characteristics of these materials impose the need for thermal pre-treatments for their recovery, such as torrefaction. Thus, this study aimed to investigate the biomass of Jatropha curcas as affected by water availability and its response to the torrefaction process. This research analyzed the biomass physical, chemical, and energy characteristics. TGA/DTG evaluated the thermo-degradation profile, and infrared spectroscopy (FTIR) determined the aromatic chemical structure. The fresh biomass of epicarp and cake presented different behaviors regarding water availability conditions, as variations in lignin contents from 29% to 2.7% and 30.9%–5.7%, respectively, and extractive range from 45.3% to 19.8% and 44.6%–21.6%, respectively. Torrefaction contributed to the increase in physical-chemical characteristics such as lignin and fixed carbon levels, from 29% to 82.4% and 19.8%–52.7%, respectively, and net calorific value of biomass, valuing them for energy use, as well as to decrease in the content of volatile materials from 80.7% to 71.8%. Using renewable biomass of Jatropha curcas cake and epicarp for energy purposes contributes to the reduction of environmental impacts by reducing the disposal of these residues in the environment, providing a sustainable and more efficient destination.