Decarbonization Analysis of Mobile Sources

Oak Ridge National Laboratory (ORNL) seeks to assess technologies for reducing the carbon intensity of current mobile sources, especially the hard-to-electrify marine, rail and heavy-duty trucking transportation sectors. More specifically, this effort seeks to determine the efficacy of onboard carbon capture and storage (CSS) technologies and compare these against other alternative mobile energy sources, including hybrid-electric, electric, biofuels and zero-carbon fuels (ammonia, hydrogen, methanol, etc.). Mobile sources pose unique technical challenges associated with packaging and energy requirements, onboard storage of captured carbon dioxide (CO2), and operational profiles. For instance, mobile sources often have highly variable exhaust flow rates, temperatures, pressures and exhaust gas chemistries. A research team comprised of vehicle/engine and carbon capture experts will assess the energy needs, operational boundaries, capture efficiencies and packaging limits of selected CCS technologies for use with mobile sources based on technical, economic and life cycle considerations. For each mobile source, each CCS method will be evaluated and ranked according to energy and space requirements, including opportunities to utilize waste heat, regenerative braking (for terrestrial applications), and ram air (for cooling). The effort will also evaluate the energy and infrastructure needs associated with direct air capture (DAC) for a level baseline cost comparison. The ORNL team will investigate the associated technical challenges and feasibility, while colleagues at the National Energy Technology Laboratory (NETL) will conduct parallel techno-economic and life-cycle assessments of the different technologies under consideration. At the end of the project, a report will be delivered describing the operational boundaries associated with the technologies evaluated, as well as identifying opportunities and pathways for feasible carbon capture system designs and implementations for mobile systems.