Biofeedstocks

Biofeedstocks are renewable biological materials used to produce energy, fuels, chemicals, and materials. They include agricultural residues (for example, straw and husks), dedicated energy crops (such as switchgrass and miscanthus), forestry byproducts, aquatic biomass like microalgae, fats and oils, and organic waste streams. Biofeedstocks are distinguished from fossil resources by their renewable origin and potential for lower net greenhouse gas emissions, though actual savings depend on feedstock choice and processing technology.

Conversion pathways include biological and thermochemical routes. Fermentation converts sugars to ethanol or other alcohols; anaerobic digestion yields biogas; transesterification produces biodiesel from fats and oils; gasification followed by Fischer–Tropsch synthesis can produce diesel or jet fuel; pyrolysis and hydrothermal processing generate bio-oil or biocrude for refining. Many processes require pretreatment or enzymatic steps to break down complex polymers such as cellulose and lignin.

Sustainability and economics: Life cycle assessments assess greenhouse gas balances, energy input, land use change, water use, and biodiversity impacts. The benefits of biofeedstocks depend on agricultural practices, supply chain efficiency, and scale. Certification schemes and policies aim to ensure sustainable sourcing and to address land competition, food security, and emissions.

Challenges and opportunities: supply variability, collection logistics for residues, competition with food and land use, and capital costs influence viability. Advances in breeding, pretreatment, and integrated biorefineries seek to improve yields and co-product streams, while policy support and market development shape adoption.