Newcomer Zephyrus Marine has signed a preliminary deal with Mirai Ships to build pioneering vessels that will produce zero greenhouse gas emissions as they serve offshore wind farms.

The battery technology provider said the memorandum of understanding with the Japanese shipbuilder envisions construction of a wind farm service operation vessel (SOV) with smaller crew transfer vessels (CTVs) that use PwrSwap, a battery swap technology developed by Shift Clean Energy.

“We need to make it easy for shipowners and the offshore wind sector to go zero carbon,” said Rob Stewart, director at UK-registered Zephyrus.

“By partnering with Mirai Ships in building our unique solution, we can move the needle towards a net zero shipping industry and we can do so while improving the operational cost and reducing the risk profiles within the offshore Japanese wind sector.”

The Zephyrus Zero Carbon Offshore hub is designed to meet the needs of the Japanese offshore wind sector, according to an announcement by Shift Clean.

The design involves building a fully electric SOV mothership that will serve both as a hotel and a charging station for the electric daughter vessels that can be stowed on deck or return to shore. The CTVs will be designed by the UK’s Ad Hoc Marine Designs.

When the daughter vessels’ charge is low, they will be able to return to the mothership and dock at its stern, where spent batteries can be swapped with fully charged replacements in minutes.

Class approval

Japanese classification society ClassNK has approved the PwrSwap modular battery systems, which Shift Clean says save space, weight and costs.

Zephyrus will utilise the batteries on a pay-as-you-go energy subscription contract.

Delivery is estimated for the first quarter of 2024.

Subscribe to Green Seas
Get our weekly newsletter on sustainability, ESG and decarbonisation to stay on top of the developments as the shipping industry faces pressure to transform.

“It is a challenge and requires dedication, passion, and, most of all, teamwork,” said Takeyoshi Kidoura, chief executive of Mirai Ships

“As JFK once said, ‘Our problems are man-made; therefore, they can be solved by man. Man’s reason and spirit have often solved the seemingly unsolvable. I believe they can do it again’. I believe he was correct, and we can do this in Japan as well.”