Waste Algae for Bioenergy Generation to Mitigate Eutrophication and Greenhouse Emissions in Water Bodies

Eutrophication has a significant negative impact on the ecosystem since it depletes the planet's biological resources and is further responsible for climate change. It is caused by both endogenous and exogenous nutrient enrichment. This phenomenon degrades the water quality and simultaneously increases the greenhouse gases emission from waterbodies resulting in climate change Inland waterbodies contain enormous amounts of nutrients such as phosphorous, nitrogen, and carbon. Thus, it becomes essential to restore these nutrients using proper sustainable approaches. Algae-based technologies have received a lot of attention these days because of environmentally friendly and inexpensive treatment. About 70% of the nutrient load from wastewater can be removed using such technology. The recovered algal biomass after wastewater treatment contains various biomolecules which can be used for the producing of value-added products such as bioenergy in the form of biomethane and biodiesel, cosmetics and pharmaceuticals along with the synthesis of nanoparticles. Therefore, the primary goal of this review is to inform readers about the possibilities of a low-cost integrated biorefinery based on microalgae for resource recovery and to mitigate eutrophication and greenhouse gas emission from water bodies.