Advancing circular bioeconomy through systematic review of multi-product biorefinery approaches for water hyacinth based renewable energy.

The global shift toward sustainable energy has spotlighted water hyacinth (Eichhornia crassipes) as a promising biofuel feedstock due to its rapid growth and lignocellulosic composition. This PRISMA-based systematic review and Covidence software, evaluates studies from 2015 to 2025, to synthesize technological pathways, cost structures, and environmental trade-offs. Water hyacinth biofuels can reduce levelized cost of energy (LCOE) by 25%, increase ethanol yields by 40%, and improve sugar release by 50%. Multi-product biorefineries enhance viability and offset up to 2.5 tons CO2/ha/year. Yet, pilot-scale data, policy alignment, and ecological safeguards remain limited. This review identifies five regional implementation frameworks integrating techno-economic, ecological, and social dimensions. Findings highlight opportunities for circular bioeconomy transitions in developing regions and propose scalable models to transform invasive biomass into renewable energy solutions.