The world’s need for sustainable energy solutions has strengthened the search for renewable and eco-friendly alternatives. Water hyacinth (Eichhornia crassipes), extremely invasive aquatic plant, has considered as a gifted biomass resource for biofuel production. This chapter reports the application of water hyacinth as a sustainable energy resources. Its appraisals the plant’s biological characteristics, chemical composition, and suitability for producing biogas, bioethanol, and biodiesel. It also explains detailed thermal kinetic analyses, models like Flynn–Wall–Ozawa (FWO), Kissinger–Akahira–Sunose (KAS), and Starink, validate the pyrolysis behaviour of different biomass parts, revealing understandings into activation energy and decomposition mechanisms. It also explains the previous experimental findings on energy yield from biogas and bioethanol and gives emphasis to process optimization. The environmental and economic impacts highlight water hyacinth’s dual role in mitigating invasive species propagation and contributing to green energy systems. As a final point, future diagnoses focus on advanced biofuel technologies, application of nanocatalysts, and circular economy integration, presenting inclusive pathway for sustainable energy innovations.