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The Science of Hybrid Propulsion: The Great Debate

Following up Technical Editor Nigel Calder's 2-part series, marine expert and PassageMaker contributor Steve D'Antonio takes a stab at why he believes the marine world is not yet ready for Hybrid technology.

Editor's Note:Following up Technical Editor Nigel Calder's 2-part series, marine expert and PassageMaker contributor Steve D'Antonio takes a stab at why he believes the marine world is not yet ready for Hybrid technology. Leave us a note in the comment section below and let us know what you think of hybrid technology and if you would consider making it a part of your cruising.

 Too Complex for Marine Industry, D’Antonio Says

To his credit Calder’s two-part series on the subject begins with, “For the past five years I have been involved in research to determine if hybrid propulsion technology represents a viable alternative to conventional marine propulsion systems. I have come to the conclusion that the answer is a more or less unqualified ‘Yes’, [are these not contradictory?] but not necessarily for the efficiency reasons cited by most proponents.”

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In short, while making it clear that hybrid propulsion isn’t as efficient as some have claimed, he advocates the use of this technology to improve the quality of life while afloat. Quoting Calder again: “The powerful generator and large battery pack [associated with hybrid propulsion systems] are an enabler for more extravagant lifestyles. It is these lifestyle issues—lots of house power and substantially reduced engine run times with the concomitant silence and freedom from exhaust emissions—that will ensure the success of hybrid systems.”

I’ve worked on and with marine propulsion and electrical systems for more than 25 years, and one fact has been made plainly evident to me, the marine industry is very good at innovating, there’s no end to its creative and marketing genius, it’s inspiring to be sure; however, we struggle when it comes to supporting, maintaining and repairing systems, particularly cutting edge technology.

Even if one assumes hybrid propulsion systems are more efficient for onboard energy production or propulsion (something we’ve been told over and over again by a host of manufacturers, yet now after five years of intensive, well-funded study, Calder tells us this isn’t necessarily so), I remain reluctant to embrace them for one overriding reason: Hybrid systems are extremely complex, and I don’t believe their manufacturers or the industry at large will be able to maintain, troubleshoot or repair them efficiently and cost-effectively. The net benefit simply isn’t worth the risk and expense.

It’s challenging enough for boat owners to get conventional propulsion and electrical systems installed, serviced and repaired without increasing their complexity by an order of magnitude. My fear is boat owners will be left holding the proverbial bag, and it will be an expensive one.

Instead, we are asked to believe that these incredibly complex, computer-controlled charging systems, which are intertwined with the most sacred and vital system aboard your boat, propulsion, are worth having for the sake of more onboard energy, quiet running at low speed, and no smoke. I’m doubtful.

Electronically controlled diesels, which are extremely efficient and reliable, are pretty quiet when properly insulated and virtually smoke-free. High-output, reliable and proven charging systems exist, and these can already power air-conditioning systems overnight on battery power, and when that’s not enough power, we have compact, efficient, reliable, relatively inexpensive (when compared to hybrid systems) generators that can fill the gap, most of which have large dealer networks and a ready supply of parts, while veritably sipping fuel.

I’m hard pressed to see how or why an industry that already struggles with support of technically complex, as well as some not so complex systems, should add to the technical and financial burden of boat owners with hybrid on board energy production and storage.

Have a Little Faith, Calder Responds

I suspect that there is little disagreement between Steve and myself on the technology or the issues associated with it. In particular, we both see the need for hybrid systems to be cost-effective and reliable, and for the marine industry to be able to develop the ability to support and service these systems. Our differences are largely related to these aspects.

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Electrical systems problems are the number one problem on boats that have anything more than a rudimentary electrical system. Ever since electricity has been put on boats, the boating industry has struggled to keep these systems running in a troublefree manner and has significantly failed to do so. Steve looks at this record and kind of throws his hands up in horror at the thought of the additional complexity of hybrid systems and their associated management issues.

I look at the way modern technology has taken our cars, for example, which used to require major attention and maintenance at regular intervals but now can pretty much be guaranteed to run at least 100,000 miles before any significant attention is required. This has been done with an enormous escalation of complexity, but with this complexity hidden from the user and working reliably in the background. I believe over time, and undoubtedly with considerable teething problems, hybrid technology will evolve into a similar solution for the problems that have plagued the electrical systems on our boats.

Maybe this is because I wear rose-colored glasses! We shall have to wait and see!

D'Antonio's last word

Although I respect his position and expertise, Nigel is correct; we do take a substantially different approach.

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Nigel may be an eternal technical optimist because he operates in a rarified world of manufacturer’s facilities, labs and his own test vessel. I, on the other hand, work from the trenches; I guide boat owners and buyers (and builders) on a daily basis, on many occasions I serve as their confidant and sea counselor, listening to and assisting them in resolving their vessel’s woes, and as a result I take a more pragmatic view.

The automobile analogy is one I hear often and it’s a stretch at best, by the time Toyota made the 10,000th Prius, they pretty much had it perfected. The marine industry is fortunate to be able to make five boats that are exactly the same, much less hundreds or thousands.

Complex systems can be done right and they are done right by a handful of boatbuilders and equipment manufacturers. In virtually every case those ‘done right’ systems are the result of exhaustive engineering, thorough real-world testing and exemplary support from those manufacturers, today, tomorrow and five or ten years from now.

Will hybrid propulsion and power generation system manufacturers be around to service, repair and provide parts for these systems today and five or ten years from now? Some early adopters have already discovered the answer to this question, and so have I, having supervised the removal of one of these hybrid system aboard a 70-foot motor yacht because it was dreadfully unreliable and ridiculously complicated.