Evaluating the utilisation of clean fuels in maritime applications: A techno-economic supply chain optimization

Interest in reducing the environmental impact of maritime shipping operations has recently been induced by the International Maritime Organization's latest set of regulations. Consequently, this study involves a macro-level view of the entire supply chain, emphasizing how liquefied natural gas exporters can reduce the environmental impact of shipping activities of energy commodities (LNG, hydrogen, ammonia and their blends) through greater uptake of cleaner fuel alternatives. This study tests the notion that demand for alternative fuels will continue to increase as the transportation sector integrates cleaner fuels to comply with increasing environmental regulations. Using Qatar as a case study, linear programming was used to develop a mathematical model where several scenarios are assessed, and the optimal combination of fuels sold, and bunker fuel consumed is determined. Firstly, by looking for maximum profit given the constraints imposed; secondly, by looking for minimal greenhouse gas emissions under the same constraints; and thirdly, by looking for maximum profit and minimum environmental impact. Results demonstrate that cleaner fuels can reduce emissions of maritime industry. While solving for minimal emissions regardless of profit, outcomes suggest that LNG is the most favourable fuel to sell due to the high demand and high production capacity, whereas NH3 is the most favourable for fuelling ships. This solution yielded a significant reduction of CO2 emissions as opposed to that expected from HFO.