The SynBios project in Bologna, Italy, is revolutionizing the treatment of wastewater by transforming it into green energy sources like hydrogen and biomethane. This initiative, led by Gruppo Hera, aims to convert renewable energy and wastewater into valuable resources that contribute to a greener future. The plant utilizes power-to-gas technology to convert renewable electricity into synthetic natural gas, effectively reducing pollutants at the sewage treatment plant. By repurposing wastewater and sludge that was once considered waste into energy sources, the project demonstrates a circular approach to waste management. The SynBios plant's core objective is circularity, with the project being hailed as a flagship circular economy project by Gruppo Hera. Through innovative technologies like Proton Exchange Membrane (PEM) for hydrogen production and biological reactors for methane synthesis, the plant upgrades biogas to biomethane, which can be injected into the natural gas network. This process not only generates energy but also enhances the quality of the purification process and contributes to decarbonisation efforts. Once operational, the SynBios plant is expected to have a significant environmental impact, preventing the release of carbon dioxide equivalent to that of 400 cars annually. This aligns with Gruppo Hera's and Italy's decarbonisation goals, positioning the country as a leader in sustainable energy practices. Additionally, the project promotes sector coupling by integrating gas and electricity distribution in a circular regime, showcasing a forward-looking approach to industrial synergy and sustainable development. The SynBios project in Bologna exemplifies how innovative initiatives in the energy sector can drive positive environmental outcomes and support a transition towards a more sustainable future.