Path to zero emissions? Leave room for larger batteries

Offshore charging

Meantime, the next big thing in ESS could be offshore charging. In early 2023, a powerful Norwegian-driven consortium launched a three-year project that aims to develop zero-emission solutions to connect vessels to the power grid in the windfarm itself. Funded by the Norwegian government to the tune of Nrk38M [US$3.6M], the Ocean Charger programme would mean batteries are recharged at sea without the use of fossil fuel. It would apply to a wide variety of vessels, including OSVs. The official aim is to “power operations at the field, without using any additional energy sources.”

Lead by Vard Design, the project involves other Norwegian heavyweights in the pursuit of zero-emissions for OSVs and other vessels. The collaboration comprises Rem Offshore, which has a fleet of OSVs, Solstad Offshore, the not-for-profit Sintef Energi, Norwegian Offshore Wind and Marine Energy Test Centre, energy giant Equinor, Ireland’s renewables group Source Energie, US hydrogen fuel-cell manufacturer Plug Power, Marine Energy Test Centre, University of Bergen, the Maritime Cleantech cluster, and Norse Research, which runs thousands of maritime consultancy projects around the world.

With its Blue Whale technology having completed sea trials late last year and now ready for delivery, Corvus is also involved in the Ocean Charging project. The ESS specialist sees a big future for Blue Whale in OSVs: “The wind segment is next in line for full zero-emission operations,” predicts Mr Husøy. “With requirements for even larger battery systems, we see that Blue Whale has great potential for this type of vessel.” In anticipation of demand, Corvus has boosted production of Blue Whale at its Vancouver plant.

“The potential for reducing emissions and costs by installing batteries is very high”

Blue Whale has been under development for nearly five years, as part of Corvus Energy’s pursuit of the next-generation ESS for maritime applications. The first product in what promises to be a series of breakthroughs, Blue Whale is designed for bigger vessels requiring high volumes of power. That is why the trials were conducted on board Seaspan Reliant, a drop-trailer cargo ferry owned and operated by Seaspan Ferries Corporation, which runs a commercial cargo ferry service between four coastal terminals on Vancouver Island and British Columbia’s mainland. Seaspan Ferries has already installed Corvus systems on four dual-fuel hybrid ferries.

According to Seaspan, the gains emerged quickly. “During the sea trials it was impressive to witness the advantages of this new technology by discharging the battery system to 3% capacity while still outputting peak power to propel the vessel,” says the ferry group’s project manager Ahmed Khan. “We envision being able to operate on a single generator and using the battery system to maintain target speeds, which will reduce fuel costs and total engine hours. In addition, the 1.8 MWh capacity of the Reliant’s new system affords new modes of operations, such as powering the vessel by battery power only during port cargo exchanges.”

Harly Penner, Seaspan’s general manager, is equally enthusiastic: “The Blue Whale system is a remarkable product which is particularly well suited for the Reliant’s existing architecture.”

At nearly 150 m-long and 26 m-wide, the dual-fuelled 2017-built Reliant certainly qualifies as a vessel requiring high energy. It has a payload capacity of 59 trailers and an ESS capacity of 545 kWh. By Seaspan’s estimates, the batteries save nearly 100,000 litres of diesel a year and knock 266 tons off CO2 emissions, quite enough for the OSV industry to take note.