Swedish ferry operator Stena Line is investigating the opportunity to convert 25 of its vessels to run on methanol. The case for methanol as an alternative fuel – and the reason why Stena prefers it to liquefied natural gas (LNG) – was presented at an IMO meeting in early February.
Converting vessels to run on methanol would be considerably less expensive and complicated than converting to LNG, said Per Stefenson, a naval architect working for Stena. Methanol can be produced from natural gas, biomass – including waste – and in the future probably from hydrogen and captured carbon dioxide (CO2). Producing it from natural gas requires about 25 per cent of the total energy compared to 10 per cent of the total energy when making LNG, meaning that LNG is cheaper and more energy efficient to produce.
Stefenson showed calculations suggesting that both LNG and methanol would have a price comparable with marine gas oil (MGO) if supplied alongside in Gothenburg, Sweden. In fact, methanol could be slightly cheaper than LNG in terms of energy supplied, and both methanol and LNG would be cheaper than MGO.
Exhaust emissions of sulphur dioxide (SO2), particulate matter (PM) and nitrogen oxides (NOx) when using methanol are equivalent to LNG, said Stefenson.
Source: Sustainable Shipping News, 4 February 2013