Biogas production from microalgae grown in wastewater: Effect of microwave pretreatment

► Microwave irradiation enhanced the disintegration and digestibility of microalgae. ► Algal biomass solubilisation increased by 800% with microwave pretreatment. ► The main parameter influencing biomass solubilisation was the applied specific energy. ► Increased biogas production rate (27-75%) and yield (12-78%) with pretreated biomass. ► Linear correlation between microalgae solubilisation and biogas yield.