As oil resources become increasingly scarce, the need to transition to renewable energy sources is ‎critical for sustainable living. The United Nations first emphasized the importance of sustainable ‎development in 1987, highlighting the "central role" of energy in this effort. After years of research, ‎innovative solutions for sustainable energy have emerged, with energy production from wastewater ‎showing significant potential. Wastewater can be converted into biogas through anaerobic digestion, ‎where microorganisms break down organic matter in the absence of oxygen to produce methane, which ‎can be used for electricity, heat, or fuel. This process not only aids in reducing greenhouse gas ‎emissions but also supports environmental protection and waste management. The growing demand for ‎renewable energy has sparked significant interest in these techniques, which utilize bacteria to generate ‎electricity, further demonstrating the potential of wastewater as a sustainable energy source. Using ‎wastewater for energy not only lowers operational costs but also allows treatment plants to generate ‎energy on-site, reducing reliance on external energy sources and lowering carbon emissions. Exploring ‎these renewable energy sources is crucial, particularly given the large volumes of wastewater generated ‎from agricultural, industrial, and domestic activities. This paper reviews the potential of wastewater as a ‎green energy source, discussing specific technologies for treating various wastewater types and the ‎associated challenges and opportunities. By examining successful case studies and emerging trends, it ‎aims to advance green energy solutions that promote both environmental sustainability and economic ‎growth‎‎.