Hermetia illucens as an innovative feedstock for biodiesel: properties, production techniques, and regulatory...

The urgent need for sustainable energy is intensifying research on biodiesel feedstocks that cut environmental impact and fossil dependence. Among these, Hermetia illucens upcycles organic waste into lipid-rich biomass, enabling a circular bioeconomy. Compared with first- to fourth-generation feedstocks (edible oils, waste cooking oils/residues, microalgae, engineered microorganisms), it avoids food competition and dedicated cropland, supports diet-tunable lipid profiles, requires no water-intensive cultivation, and has a short production cycle; indicative carbon footprint values (∼0.8 kg CO₂ eq/kg lipid) suggest advantages over conventional oils. This review critically examines the fuel properties of H. illucens biodiesel and benchmarks them across feedstocks. Under optimized conditions, literature-reported yields reach ∼94-98 % (defined here as FAME/biodiesel mass yield on a lipid-feedstock basis). The fuel shows cetane ∼50-58, kinematic viscosity 4.0-5.2 mm²/s (generally compliant, near the EN upper bound), and flash point >120 °C; water and total glycerol meet international standards. Oxidative stability reaches 7.7 h with antioxidants (meets ASTM ≥3h, typically below EN ≥8h without optimization). In H. illucens biodiesel, the acid value is usually >0.50 mg KOH/g; however, standard treatments bring it within limits. In H. illucens, diet can be leveraged to tailor both the fatty-acid profile and the lipid yield for target applications. Preliminary evidence on process energy and costs across extraction and transesterification routes indicates that economics remain feedstock-driven and depend on scale, heat/solvent recovery, and enzyme reuse. In sum, H. illucens is a scalable platform for waste-derived biodiesel; this review distills evidence and practical levers to close remaining gaps and accelerate adoption.