Wastewater treatment plants (WWTP) are said to consume significant energy and produce GHG emissions. Enhancing their efficiency is generally important to meet certain targets, especially the use of energy and the reduction of GHG emission at WWTPs. As the reduction in GHGs play a major role in promoting sustainability. This current study focuses on analysing the energy usage trends, the main sources of GHG emissions at WWTPs and at the same time suggest effective strategies for their enhancement. From the existing literature, a review has been conducted to explore the current approaches for decreasing energy consumption and GHG emissions at WWTPs.