With a major charterer stipulating a requirement for vessels with hybrid power to support their efforts to decarbonise, Norwegian ship management company Østensjø Rederi approached Wärtsilä to retrofit two of its vessels, the Edda Flora and Edda Fauna, with a hybrid/battery solution. In addition to helping Østensjø Rederi secure the new contract, the upgrade also increased their attractiveness to potential new charterers through improved efficiency and reduced maintenance costs.
Østensjø Rederi strives to be a leader in sustainable operations and to reduce its carbon footprint – goals that are shared by the energy companies that charter its vessels. In order to make their vessels as attractive as possible to charterers, an increasing number of whom are insisting on hybrid operations in their contracts, the company decided to retrofit two of its light construction vessels with the Wärtsilä HY Upgrade. The Edda Flora and Edda Fauna were built in 2008, are powered by third-party engines and are contracted mainly to conduct inspection and sub-sea work on pipelines and wells. While the Edda Fauna had already secured a new charter contract prior to the upgrade, the Edda Flora secured a renewal of its charter as a direct result of the upgrade.
A truly integrated solution
Østensjø Rederi is already well aware of Wärtsilä’s extensive experience, vast knowledge and world-leading technical capabilities, having installed Wärtsilä’s LLC (low loss concept) power distribution system for electric propulsion on a number of its offshore support vessels. The Wartsila HY Upgrade work began in July 2020, with Wärtsilä providing advice and working closely alongside Østensjø Rederi to plan, develop and install a tailored solution below deck in the vessels’ existing spaces. The work was completed in March 2021.
“We got involved at an early stage, providing a deep and honest evaluation to ensure that we could deliver the right technical solution that would be practical in the long term for the vessels’ operational profile. Other providers had over-promised on the battery capabilities, and rather than just saying what the customer wanted to hear, our more practical, realistic assessment was seen as a positive,” explains Helge Solberg, Senior Proposal Engineer, Hybrid Sales, Wärtsilä Marine Power.
“The solution leverages Wärtsilä’s expertise in marine electrical, automation and engine technology to create a single integrated hybrid power module where the individual components – including the engine, the power drives and the energy storage system – are optimised to work together.
– Helge Solberg, Senior Proposal Engineer, Hybrid Sales, Wärtsilä Marine
“Wärtsilä was the obvious choice to carry out this upgrade project, which has already been instrumental in helping us secure a new contract.
– Egil Arne Skare, Chief Project Officer, Østensjø Rederi
Wärtsilä’s highly sophisticated Energy Management System (EMS) is the ‘brains’ of the solution and controls the energy flows between the different power consumers and producers. This kind of control is not possible with conventional systems where the energy storage element is simply added to the mix without being optimised to work in unison with the other components.
Reduced emissions, fuel costs and maintenance requirements
A hybrid retrofit reduces the vessel’s exhaust emissions, energy consumption and operating costs. By using a hybrid-battery system to provide back-up and redundancy power, the ship’s main engine can operate closer to its optimum design point where it has the highest efficiency and lowest emissions.
Aside from enabling an enhanced environmental profile for the Edda Flora and Edda Fauna that makes the vessels more attractive to potential customers, the HY hybrid system benefits Østensjø Rederi in other ways too. The upgrade allows the vessels to maintain the same performance while taking one of the two main engines out of operation. This reduces the fuel and maintenance costs of the main engines and also means that the one in operation can be run at a higher, more efficient load. The upgrade also increases safety by providing instant power, spinning reserve and blackout prevention.
Improving the vessels’ efficiency also translates into increased time between overhauls and a higher rate of vessel availability.
“As a leader in marine hybrid solutions and an OEM whose qualities we are very familiar with, Wärtsilä was the obvious choice to carry out this upgrade project, which has already been instrumental in helping us secure a new contract, will enable us to deliver on our commitment to providing vessels with a strong environmental profile and help us to remain an attractive proposition long into the future.” Egil Arne Skare, Chief Project Officer, Østensjø Rederi
