Maritime Circular Methanol Cycle, Enabled by Onboard Carbon Capture and Circular Methanol Production on Floaters

Abstract This paper examines a sustainable fuel cycle that combines the production of E-fuels with a significant reduction of emissions in the maritime sector by deploying Onboard Carbon Capture on ships with floating production units for circular methanol. The paper focuses on an integrated cycle in which CO2 is captured and liquefied onboard shipping vessels, significantly reducing their greenhouse gas emissions. This technology, which has already been successfully piloted and is ready for scale-up and commercial deployment, can be applied to both new and existing ships. Upon arrival in port, the captured CO2 can be supplied to a methanol production plant that manufactures circular methanol from the CO2, using the circular CO2 as a feedstock. The key design feature of this cycle is that the manufacturing plant, in this case, is designed and built as an integrated Floating Methanol Production and Storage Unit (FMPS). This enables the clean FMPS technology to be available in any port in the world, either to distribute synthetic methanol to maritime shipping or through other synthetic fuel value chains. The floating facility has a number of advantages: Relatively rapid construction, deployment and autonomous on-site start-up. Beyond established ports, the FMPS could be located at new sites where Renewable Power is potentially available in abundance and produced at a relatively low cost. In these cases, the production of green hydrogen (either on the floating unit or a shore-based facility), coupled with the ship-based captured CO2 as feedstock, produces a truly carbon-neutral fuel. To cover the energy transition period, the FMPS could also be deployed near existing industrial sites where Blue or Grey Hydrogen is produced. In these cases, onshore-produced hydrogen, together with ship based carbon captured CO2, is used as floater feedstock. Relocatable, allowing the entire plant to be moved easily if deployment is required elsewhere. Lower cost, improved safety and quality through fabrication in a controlled shipyard environment. The paper outlines the ship-based Onboard Carbon Capture (OCCS) technology whilst detailing the integrated floater technology, particularly the configuration and deployment options. Case studies, together with supporting economic analysis using the levelized cost of FMPS-produced synthetic fuel production, are presented.