Design Considerations for Methanol Fuelled Ships

In a sector where emissions restrictions are growing methanol, the simplest alcohol, is one of the most promising alternative fuels. It can be produced from different feedstock but bio-methanol from renewable sources is the only that can reduce emissions and carbon footprint over the entire chain. As sulphur-free chemical its combustion does not produce SOx emissions, NOx emissions are still present but reduced compared to fossil fuels and there are easy solutions that allows to respect Tier III regulation. It is liquid at atmospheric conditions this allows easy storage and transport; but its low LHV together with important safety measures leads to have to find large volumes on board for methanol tanks. This paper, as well as an overview on methanol as fuel on board aims to do design considerations and, in particular, on tank positioning that is one of the barriers for the adoption of methanol as marine fuel; the work is based on ABS’s guideline for methanol and ethanol fueled vessels. The green alternative has been analysed also from an economic point of view, with an OpEx-CapEx evaluation for the ship used as case study.