Pioneering bioenergy revolution: Unleashing the acquisition potential of pine cones, needles, and resin

Pinus roxburghii (Chir Pine) residues are a serious ecological problem in the highlands of the Indian Himalayan Region that are causing regular forest fires and causing top soils to become less fertile. This detailed review provides a systematic techno‐chemical and thermodynamic framework for converting these abundant conifer wastes from a resource into a high utility, multi‐vector bioenergy matrix. The results of solid‐phase evaluations show that mechanical densification can successfully overcome the extreme bulk density problem of raw pine needles (≈60 to 80 kg/m 3 ) to produce bio‐briquettes with a high carbon density macromolecular lignin fraction (≈26%) and a strong Higher Heating Value of ≈19 MJ/kg. Due to low ash content of the fuel (≈5%), there is no need for the serious alkali‐silicate sand agglomeration and bed slagging problems associated with lowland agricultural wastes, achieving a fairly constant cold gas efficiency ≈65% with a producer gas production rate of ≈1.6 Nm 3 /kg of dry fuel. α‐pinene and limonene from pine have a Lower Heating Value close to that of petroleum diesel (≈43 MJ/kg). The ultra‐low kinematic viscosity (1.3 cSt) improves the homogeneity of fuel spray atomization, resulting in a quantitative 40% to 60% reduction in exhaust smoke opacity. Finally, this work provides a vision of future research paths with regard to selective catalytic ring‐cracking of bicyclic terpenes and suggests policy instruments to economically promote “local” bio economies in mountain regions.