Practical Application of Energy Storage in Hybrid Commercial Vessels
By Grant Brown, VP Marketing for PBES, Published in The Journal of Ocean Technology
Marine engineers have long been aware of the potential efficiency increases from hybridizing their onboard energy systems; the ability to optimize the use of diesel generators by storing excess energy and using it to provide propulsion during low load times.
However, only recently has the battery technology been improved to the point of allowing large-scale systems to survive in a commercial marine environment. Not only do these new energy storage systems survive, they are designed for and excel in commercial marine environments. Hybrid tugboats, offshore supply vessels (OSV), ferries and a variety of other purpose-built vessels all derive huge efficiencies from the use of onboard energy storage.
These hybrids range from new builds to retrofits of existing vessels. Payback on investment is a critical component in the decision to convert or build a hybrid workboat. However, an often overlooked benefit is the redundancy and increased safety offered to the operator of a hybrid vessel. A vessel employing a large battery or energy storage system (ESS) not only operates more efficiently, it also has an ability to draw upon a reserve of energy instantly. This pool of energy may be used as spinning reserve to keep the vessel from harm’s way in the event of power loss, provide emergency navigation and hotel loads, auxiliary propulsion power, and even extra bollard pull to the main drives in the event of an emergency situation while towing. While these and other advantages, such as the environmental and cost savings benefits, are well-documented, real world lessons learned by an experienced integration and engineering team are exceptionally valuable. This experience helps vessel owners, operators and designers understand how to design and integrate a lithium energy storage system for safe, reliable use, now and for years to come.
Simply put, batteries will reduce a vessel’s exposure to risk and make it fundamentally safer to operate, while providing economic gain for vessel owners.