Norway’s Vard develops ocean charger: Offshore wind charging for service operation vessels

Vard, the Norwegian shipbuilder and ship designer, is working with sister company Seaonics to develop Ocean Charger, offshore wind turbine-based battery charging, primarily designed for Service Operation Vessels, (SOVs) that service offshore wind farms.

The Ocean Charger concept was officially launched in February 2024. Vard says: “Now, with a strong consortium of industry and research partners, VARD will lead the way from research to testing, validation, and commercialization of new technological solutions for energy transfer to battery-powered ships offshore.”

High-voltage charging tests were conducted in port to charge the batteries on the Rem Offshore-owned diesel-electric hybrid CSOV (Construction Service Operation Vessel) REM Power (built 2023) as well (as) offshore from a charging point (cable reel, winch, and control system) mounted on a wind turbine.

In a September 10th announcement, Bjørnar Huse, Sales Manager, Offshore Energy at Seaonics explained: "At 10 years old, the turbine is one of the smallest offshore, but the prototype proved it is possible to install the Ocean Charger on an existing turbine and charge an SOV from day one, using 11 kilovolt (KV) current delivering 6 MW of charge. Apart from a handful of improvement points to fix, the concept and control system are complete, and the product is available for sale as is. We're first in the market and already in talks with wind farm owners."

He adds that because power current varies between wind parks and wind turbines, the commercial version will have to be customized for each project.

SOV A Game Changer

The ability to charge vessels offshore in a cost-effective way is a central enabler for shipbuilders to deliver zero-emission SOVs to the offshore wind industry. "Connecting vessels to the power grid in the wind farm and charging batteries regularly is a big step towards increasing sustainable operations without using any additional energy sources. It saves the time and energy needed to return to port to charge, while the operating cost of electric SOVs versus diesel and alternative fuels is much lower, because both the energy is cheaper, and you reduce engine maintenance demands. You still need diesels for back-up power, but quite a lot smaller than for a full diesel operation, with lower Capex," said Huse.

A large, 60-person SOV consumes 20 to 25 MW hours per day, so at 6 MW it is possible to charge for a full day's SOV operation in three to four hours. "But it's better for the lifetime of the battery pack to never be completely depleted nor fully charged – between 50 and 80 percent is best. You could charge for six hours at night, say, then do ad-hoc charging during the day," Huse said.

Meanwhile, wind farm owners are moving away from the idea of locating charging points on a substation or expensive floating buoys. "The standard will most likely be to locate the charging point on a turbine. Downscaling the weight and cost also means you can have many charging points reducing the need to cruise long distances to charge. The turbines are usually owned by the developer, so they can fit as many as required. It is easier mechanically to have charging points on a substation but as these are usually owned by the grid owner, there is some doubt as to who would be responsible for their maintenance and insurance etc. This will have to be sorted out project by project," Huse added.

Ocean Charger Project

In December 2022, the Ocean Charger project was awarded the equivalent of $3.6 million U.S. dollars through the Norwegian Government's support.

The Norwegian Minister of Trade, Industry and Fisheries, Jan Christian Vestre, launched the new project at a press conference in Oslo: "We are carrying out the largest restructuring of the Norwegian economy ever. Everything will become greener. It is private companies that must lead the way in this transformation, with the public sector as a supporter," Vestre said.

The Ocean Charger was developed by a consortium led by Ålesund-based Vard Design and sister companies Seaonics and Vard Electro, alongside partners Rem Offshore, Solstad Offshore, SINTEF Energi, SINTEF Ocean, DigiCat, Sustainable Energy, Equinor, Source Galileo Norge, Corvus Energy, Plug, Shoreline, Sustainable Energy, University of Bergen, Norce and Maritime CleanTech: "Coming up with a pioneering product at speed demonstrates what great partners with different expertise can achieve in collaboration – which is the only way to accelerate sustainability in our industry," Huse concluded.

Transitioning To Battery-Powered PSV’s & SOV’s

Oystein Longva, Chief Technical Officer, Vard Electro, told AJOT, “We looked at the possibilities to have a full electric PSV (Platform Supply Vessel) operating in and out from the oilfields. We saw that this is possible if there are possibilities for the vessel to charge offshore. After this, we realized that this is even better fit … in the offshore wind industry and since we currently are building a lot of SOVs (service operation vessels for offshore wind), we started the … Ocean Charger project to build and do a full-scale live test of an offshore charger. This test was performed outside of Norway at the floating wind turbine Zefyros.”

Longva said that the Ocean Charger solution is leading the transformation: “Ocean Charger is a joint delivery from Vard Electro and Seaonics (Seaonics is also a company 100% owned by Vard). Vard Electro delivers the charger and the PMS (Power Management System) on the vessel. Seaonics delivers the 3D compensated crane and the plug holder on the vessel, and the cable winch on the offshore structure … “

The “SOV is operating “in the wind farms and the PSV are operating in the oil fields. A Dynamic Positioning (DP) system keeps the vessel at a fixed position … You want to keep the vessel in position … And then it's much more efficient if you do this with electric power, because almost all our vessels do have electric propulsion,” Longva added

On the offshore wind farms, maintenance and repair work is sizeable and requires the transport of 60-100 workers going from wind turbine to wind turbine: “So they are going … with a lot of people on board, maybe 60 to a 100 people ... And then they go from turbine to turbine and deploy people. Then they work … during the day, and then they pick them up again: “Because of this we do the charging during night to not disrupt the operation during the day …”

Longva says “this is an operation that can be automated in the future, but the first step can maybe be … remote control.”

Automated Systems

Vard is also developing more automation in the ship engine room. The Vard designed engine room utilizes cameras, monitoring and digitization and can allow for remote control of operations from a shore side site: “We will not remove everyone but slowly reduce manning,” he says.

Longva says more functions may need to be automated because mariners find being away from home for four weeks at a time challenging: “It is not easy to get people to go on to offshore vessels because … in our region, they typically are out for four weeks, are away from their family and everything, and then they are all back home for four weeks. And then they go out for four weeks again. And we see now that people would like to stay closer to the family and have their weekends and so on. And this is also our … reason because to attract crew is not that easy anymore. “

Corvus Norway is a leading battery power supplier to the global maritime industry. Corvus is at the forefront of the adaptation of hybrid-electric propulsion technology. Many groundbreaking electric and hybrid projects for the marine industry are powered by Corvus Energy battery systems.

Corvus Norway have supported the project with models to ensure accurate simulation models for dimensioning of battery packs, life cycle analysis and battery arrangements: “We see that the concept of battery-electric PSVs is feasible and when we now also realize offshore charging through our innovation Ocean Charger, this will be very attractive for the offshore and renewables market,” according to a Vard representative.