The Week in Alt Fuels: The grid is the limit

This week brought significant developments in the world of alternative fuels, particularly focusing on the challenges of powering larger ships. A 41 MWh battery ferry began operation between Argentina and Uruguay, marking the first fully electric ship of its kind. Meanwhile, a 151 MWh container ship design was approved by the American Bureau of Shipping (ABS), designed to run on a battery energy storage system that is three times larger than the battery on the 41 MWh ferry.

The 41 MWh ferry, operated by Buquebus, is capable of sailing for up to 1.5 hours on battery power alone. However, the company acknowledged that the harder part lies in providing sufficient power at the quay. Battery-electric ships are no longer limited to short routes, as demonstrated by the new electric fast ferry ordered by Spanish operator Baleària. This 87-meter vessel will sail between Tarifa in Spain and Tangier in Morocco, starting in summer 2027.

Hanwha Power, a South Korean conglomerate, developed a concept design for a 1,700 TEU fully electric container ship, with a 151 MWh battery system. The batteries are in containerized units that can be replaced, allowing for potential decarbonization of short-sea and regional container shipping. However, the design still relies on port charging for direct operation without carbon emissions.

The shift to electrification moves the energy-system burden from the vessel to the port, requiring megawatts to tens-of-megawatts of power for charging large vessels during short turnarounds. This demand can exceed local distribution capacity, leading to severe demand-charge costs. For instance, charging a 151 MWh battery like Hanwha's from empty would take nearly four hours at the Port of Valencia, a city investing in grid capacity for its cargo terminals and shore power for ships at berth.