The Adoption of Liquefied Natural Gas as a Ship Fuel: A Systematic Review of Perspectives and Challenges

Abstract

The stringent ship emission regulations under IMO's (International Maritime Organization) MARPOL Annex VI are a main driver to consider liquefied natural gas (LNG) as a ship fuel. Research into LNG as a marine fuel saw a strong growth in recent years, but no study has analyzed in a systematic way the level of convergence among the findings presented in the wide range of studies. In order to fill this gap, this paper seeks to perform a systematic review to synthesize the findings of 33 published studies on the use of LNG as a ship fuel. The aim is not only to obtain a much broader understanding of the current perspectives and challenges for applying LNG as a bunker for ship propulsion, but also to identify the gaps and weak points in the literature which could suggest future research. Moreover, given the output of the synthesis, the paper presents an extensive decision-making framework for shipowners when deciding on a fuel switch for their fleet from conventional oils to LNG in order to achieve a level of conceptual development beyond that attained in individual studies. In addition, the study also identifies the important role of ports in facilitating and encouraging the large-scale adoption of LNG in the maritime industry.

Keywords:

• LNG
• ship fuel
• ECAs
• air emission
• systematic review
• research synthesis

Notes

1. IMO MARPOL Annex VI sets stricter standards for the sulfur content of marine bunkers and sets stringent limits on NO_x emissions from ship engines, especially in ECAs. The current sulfur standard for ship fuels in ECAs is at 1% and will further be reduced to 0.1% from January 2015. The NO_x emission (Tier III) limits enforced only in ECAs requires 75% NO_x reduction for ships built after 2021.

2. Porter's five forces include three forces from ‘horizontal' competition: the threat of substitute products or services, the threat of established rivals, and the threat of new entrants; and two forces from ‘vertical' competition: the bargaining power of suppliers and the bargaining power of customers.

3. Twenty-four of the 33 selected studies refer to this issue. Through checking the studies marked with colors (no matter what color is) in Column Nos. 1–3 in the table of Appendix 5, it is known which 24 studies discuss this factor.

4. SIGTTO: Society of International Gas Tanker and Terminal operators. OCIMF: Oil Companies International Marine Forum. IGC code: International code for the construction and equipment of ships carrying liquefied gases in bulk.

5. It means the studies marked with the color light green (L.g.) in Column No. 2 (Col.2) in the table of Appendix 5 (App.5) are the referred literature. The same method is adopted in the rest of the paper in order to link the synthesis to the original literature. Please note that the four colors are noted as D.g. (Duck green), L.g. (Light green), R (Red) and O (Orange).

6. DNV: Det Norske Veritas; LR: Lloyd's Register; GL; Germanischer Lloyd; ABS: American Bureau of Shipping.