Study: Battery Power Could Work for Boxships

Battery-electric propulsion could offer the container shipping industry an effective route to decarbonization if mechanisms are put in place to lower the costs of battery and charging points are deployed along shorter maritime routes, a new study suggests.

The new study - written by three energy researchers at Lawrence Berkeley National Laboratory - suggests that it could be possible to install cost-effective batteries in container ships covering a distance of up to 2,700 nautical miles, a development that would significantly cut down CO2 emissions for regional routes like those in the Mediterranean, the Baltic or East/Southeast Asia. 

Though the focus of the shipping industry has been centered on electrofuels for mid- and long-distance freight shipping, the study published in Nature Energy suggests that at battery prices of $100 per kWh, the electrification of feeder routes under 550 nautical miles would economical, with minimal impact to carrying capacity. If the environmental costs of bunker fuel were priced in with carbon pricing, and the cost of batteries fell by half, the economical range would rise to 2,700 nautical miles or more.

The study shows that if vessels were able to stop and recharge at stations en route, the battery cost, lost TEU capacity and additional energy requirements from battery weight would each decrease, potentially making longer-range trips economically feasible. Picking the right charging location could minimize impact on schedule. 

“Battery-electric propulsion has been underexplored as a potential low-emissions alternative in the marine shipping sector, despite its considerable emissions reduction potential, recent decline in battery costs, improvements in battery energy densities, increasing availability of low-cost, renewably generated electricity and its substantial efficiency advantage over e-fuels,” states the study.

Implementation might not be far off. Yara Birkeland is credited with developing the world’s first electric battery-powered container ship, and Maersk is among shipping lines that are piloting battery hybridization on boxships. Similar battery-electric vessel projects are underway in Japan, Sweden and Denmark, some involving cruise ships.

According to the study, several challenges need to be addressed for commercial deployment. Notably, the operating costs of battery-electric ships are much lower than those of conventional ships, but their upfront costs are much higher, primarily due to the cost of batteries. This capex-intensive model would require different financing mechanisms.

Moreover, grid-connected charging stations with capacities in the hundreds of megawatts would have to be built to support ship charging.