Optimizing the logistics of compressed natural gas transportation by marine vessels

Compressed natural gas (CNG) has been recently proposed as a potentially economical alternative to liquefied natural gas (LNG) for marine transportation of relatively modest amounts of natural gas over short distances. Because the main capital expenditure in a CNG project is on marine transport vessels, careful design of CNG transport fleets and compatible distribution plans is important. In this work, a structured optimization framework is developed to uncover trends and patterns for optimal selection of the number and capacities of CNG vessels along with corresponding schedules for CNG distribution. An important conclusion from this analysis is that medium-capacity vessels may result in lower capacity for an entire fleet, thus offering significant economical advantages. A case study of potential CNG distribution in the Caribbean illustrates the proposed approach.