Residual organic and food wastes can offer a quasi-renewable and low-carbon source of energy. By processing organic wastes, often under high temperatures, pressures and in the absence of oxygen, organic wastes can be transformed into fuels, which can be used for heating, electricity generation, as well as transportation. A variety of technologies have been developed to generate biogas from organic materials, for example, anaerobic digestion. Such facilities can vary in scale from single units that can process the waste of a single building or neighbourhood, to large-scale facilities that can process the majority of the organic wastes generated from the entire city.

Cities have a key role to support the utilisation of organic materials as biofuels due to their close oversight and influence on the urban waste management system. In particular, cities can support the financing of large-scale facilities to help to overcome the investment costs, as well as develop relationships with businesses to operate such facilities.