Using Source-Separated Organics to Create Renewable Natural Gas for Vehicle Fuel

The City of London will complete a feasibility study to determine whether they should use refined biogas from the anaerobic digestion of source separated organic material (SSO) from curbside collection (and possibly biosolids from satellite wastewater treatment plants) to fuel municipal vehicles. The City of London garbage packers and other heavy-duty fleet vehicles are currently fuelled with a diesel blend using 5% biodiesel. Substituting diesel for compressed natural gas (CNG) reduces greenhouse gas (GHG) emissions by 15-25%. The City of London plans to blend a portion of renewable natural gas (RNG) produced from biogas with CNG in order to limit the use of fossil fuels and further reduce greenhouse gas emissions. This strategy might also make the curbside collection of organic material in the City of London economically feasible by offsetting the costs of fuel purchase for municipal vehicles. As part of the feasibility study, consultants will gather data from City of London staff, technology suppliers, and relevant utilities pertaining to both the economic case and the environmental impacts of the proposed project. From the economic standpoint, they will analyze the volume of RNG that could be produced from City of London's projected SSO volumes, the compatibility of waste water treatment bio-solids with SSO in an anaerobic digester, RNG production cost, and regulatory requirements. From an environmental perspective, they will compare GHG emissions from proposed CNG/RNG blends with diesel and biodiesel blend. Union Gas will also work with the City of London to identify potential private and public sector fleets that may transition to CNG and RNG. Rough estimates indicate that RNG from SSO has the potential to fuel 45-60% of the city fleet, 15-20% of London Transit Commission (LTC) buses, or comprise about 1% of community-wide diesel use. The proposed project supports the Vehicles and the Transportation System strategy under London's Community Energy Action Plan. The city may also consider sale of its RNG resources for private commercial CNG fleets, which would represent an innovative financial model and GHG reduction opportunity for the community and its transportation sector. The city is committed to knowledge sharing through their participation in the Quality Urban Energy Systems of Tomorrow (QUEST) RNG Working Group, and the Canada Biogas Association. (Project description from original funding application)