Economic feasibility of an alternative fuel for sustainable short sea shipping: Case of Cross-Taiwan Strait Transport

Abstract

Marine shipping has experienced increasing pressure in recent years to reduce its emissions of the greenhouse gases and many key air pollutants. The use of liquefied natural gas (LNG) as ship fuel has been proposed as one of the effective solutions for the problem, mainly because it makes possible simultaneous reduction of both greenhouse gases and key air pollutants. In this study, we want to find out whether the technology can still be as beneficial a solution for ships operating in Taiwan Strait, where no ECA is currently designated while the LNG prices are typically much higher. We analyzed the economic feasibility of retrofitting existing vessels to run on LNG, using two typical types of vessels operating across the Strait as examples, one feeder and one ferry. We considered two different scenarios of HFO price forecast and three scenarios of LNG price forecast, and evaluated the fuel switch based on net present value, annualized net benefit, and the discounted payback period. Consistent with previous studies, our result found that the economic feasibility depends on the price differentials of HFO and LNG. Furthermore, we found the feasibility varied across types or operation methods of vessels. It is generally more feasible for the feeder than for the ferry. The technology investment has positive net present value under most scenarios for the feeder, but only half of the scenarios for the ferry. The investment requires payback period of more than 10 years under all but two cases, with the shortest one being 6.78 years. Marginal abatement cost ranges from -0.126 to 0.040 USD per kg-CO2e when considering GHG reduction alone, indicating minimal economic benefit realizable from the application. As a result, we suspected the strategy would attract as much interest from the marine shipping companies operating around Taiwan Strait.