Large-scale shipping of low-carbon fuels and carbon dioxide towards decarbonized energy systems: Perspectives and challenges

To meet the projected increase in global demand for energy while tackling sustainability concerns, the widespread adoption of renewable energy is inevitable. Once harnessed, exports of this renewable energy from regions with excess resources are anticipated to those that will require imports of energy. The shipping sector will thus play a pivotal role in enabling such trade through energy carriers such as hydrogen, ammonia, methanol, and liquid organic hydrogen carriers. Furthermore, in addition to these energy carriers, carbon dioxide is also expected to become an important maritime trade commodity to achieve climate targets. Through the deployment of carbon capture utilization and storage, and more recently, negative emission technologies, carbon dioxide will need to be transported to regions with the appropriate infrastructure and resources necessary for their anticipated implementation. Presently, in light of these circumstances, the lack of experience in shipping a number of these energy carriers and carbon dioxide must be addressed. As such, an understanding of the techno-economic and environmental feasibility of the large-scale shipping of these commodities must be established at all scales of operation. Accordingly, this work proposes the use of process systems engineering based approaches to enable the marine transportation of these future energy carriers and carbon dioxide from a multi-scale perspective. To lay the foundation in support of this initiative, a framework that considers the multiple scales involved is then presented for the design and operation of progressive ships and their supply chains as part of a decarbonized energy system.