Green methanol best candidate to make shipping climate-neutral - report

Climate-neutral industrial alcohol made with renewable electricity appears to be the most suitable synthetic fuel to decarbonise international shipping, researchers from the Institute of Maritime Energy Systems at the German Aerospace Centre (DLR) have found. Switching to green methanol could reduce CO2 emissions by 96 percent over the entire life cycle of ships, the researchers said in a report commissioned by NGO Greenpeace.

The International Maritime Organisation (IMO) will decide at a meeting this week in London which measures should be taken to make shipping climate-neutral by 2050. International shipping continues to run almost exclusively on fossil fuels and causes around three percent of global greenhouse gas emissions, in addition to large quantities of harmful air pollutants, such as nitrogen or sulphur oxides.

“When comparing the options according to specifications and safety, storage and bunkering, emissions, availability of technology and regulations for use on board, methanol currently shows the greatest potential,” the report concluded. Unlike hydrogen or ammonia, methanol is easy to handle and technically ready for use in shipping. Moreover, existing ship engines can be easily converted, the authors said. Producing green methanol requires green hydrogen made with renewable electricity, and sustainable CO2 from renewable biogenic sources or from direct air capture (DAC). Electrification is not a viable option for heavy shipping, because the batteries would be prohibitively large.

However, the report also listed numerous problems afflicting the use of green methanol, for example the necessity to install tanks that are twice as large so that ships can cover the same distance as with fossil fuels. In addition, green methanol has hardly been available on the fuel market to date and remains very expensive. The report said that up to 5.7 million tonnes of green methanol will be needed per year for shipping in Germany alone.

According to the authors, several different fuels will be used in the shipping industry in the long run, not just green methanol. “It is unrealistic to expect that only one alternative solution will prevail in the shipping industry. It is to be expected that various fuel options will be available on the market and that the solutions will differ depending on the type of ship, route and numerous other parameters,” the report said.

Greenpeace said the IMO should adopt binding quotas for the use of alternative fuels to ensure that shipping decarbonisation picks up speed now. “And a CO₂ price is needed that reflects the climate benefits of green methanol compared to fossil fuels,” the organisation added.