A team from ETH Zurich has mapped out “routes” towards emission-free shipping by investigating shipping activities in the North and Baltic Seas. Infrastructure, costs of new fuels and storage options have also been analysed.
Around three percent of global CO2 emissions results from shipping, making it one of the largest polluters in the transport industry next to road and air transport. The largest culprits are international merchant ships and large freighters.
Shipping companies, governments, and various organisations have therefore set themselves a joint goal: carbon-neutral water transport within the coming years. How to make this transition effectively? That´s where the ETH became involved.
A group from the Department of Management, Technology and Economics at ETH Zurich has now mapped out possible ways to achieve emission-free shipping as part of a project, which aims to translate scientific findings into sustainable practices. The study was commissioned by Christian Oldendorff, entrepreneur and co-owner of the German shipping company Reederei Nord.
North and Baltic Sea region drives innovation
According to lead author Petrissa Eckle, the North and Baltic Seas have already made a name for themselves as a driver of innovation in the shipping industry. As a relatively small area, it is also well suited for testing which solutions actually work in practice. Eckle and her team investigated routes, the existing infrastructure, sustainability and the cost of new fuel options.
Alternative energy sources that will be available in the next five to ten years and that don’t emit CO2 as the ships travel were used for the study. Synthetic fuels such as methane and methanol would in theory provide a CO2-neutral option for the shipping industry; however ships powered in this way still emit CO2 as they travel.
Another key requirement for the proposed solutions was the scalability for international shipping. Although the study did not include measures to enhance efficiency, such as optimised hull design or operational improvements, these would result in even greater energy savings and would, in turn, further reduce carbon dioxide emissions.
Ideal energy source depends on ship and route
Zero-emission propulsion systems in the form of electric motors, fuel cells or combustion engines powered by ammonia hold the greatest potential in the near future. Eckle and her team conclude that the most suitable source of energy depends on the type of ship and length of the route. “In the North and Baltic Seas, ships with electric propulsion systems are already being used for short distances, which makes sense,” Eckle says.
For long distances, ammonia would be a suitable option but due to its toxicity, its use as a fuel is not currently permitted, the report contends. As for hydrogen, there is still a lack of capacity for liquifying and transporting; testing will soon begin on the first cargo vessels.
“The next step is to run pilot projects to find answers to all the unresolved questions. We need shipping companies to test vessels with emission-free propulsion systems,” Eckle says.
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