Maritime LNG fuel systems for small vessels—A survey of patents

The goal of the Paris agreement (2015) is to achieve a climate-neutral world by mid-century. For maritime transport, the goal is a 50 % reduction of greenhouse gas emissions by 2050. This may be achieved using low and zero-emission fuels. LNG is a well-known low-carbon fuel for some ship types, but for application to medium to small-sized vessels, more cost-effective, compact, and operational robust solutions must be available. This paper discusses patented LNG fuel system designs and gives a qualitative evaluation of them with respect to their application to this ship segment. The use of a pressure build-up unit in combination with nitrogen injection, and/or heating of the LNG during bunkering, is suggested to be a feasible solution. Another aim of this paper is to highlight the role of patents within this area and contribute to the prevention of patent infringement.