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What is an 'Eco-ship'?

Article-What is an 'Eco-ship'?

What is an 'Eco-ship'?
Headlines in the shipping press recently declared “Owners are failing to get the cost benefits of fuel efficiency” and that the “Market fails to reward owners of efficient ships”.

The headlines were based on the views of researchers from the UCL Energy Institute and Carbon War Room who confirmed vessels of high efficiency do not get any premium in charter rates, whereas time charterers, who pay for the fuel, have failed to identify this advantage thus do not seem to prefer such vessels.

“Once a lucky charterer hires such an efficient vessel he can have huge savings from the reduced fuel consumption whereas the owner seems unaware of his vessel’s high fuel efficiency,” a keynote speaker told the recent Greener Shipping Summit in Athens recently.

Panos Zachariadis, a long-time member of the Greek delegation to IMO, and designer of “eco-ships” said the researchers urged charterers to exploit this missing price signal by hiring efficient vessels without having to pay and added premium for the privilege!

“This of course flies in the face of how shipping operates in the real world and is just one example of the huge misinformation and fog surrounding the world ‘eco-ship’,” said Zachariadis, before asking, “so what’s the catch?”

He answered: “The catch is how the writers define ‘efficient’.”

He said, they consider as efficient, “ships with a high Rightship environmental index”.

“I have claimed for years now this rating is nothing more than a random number generator. No wonder charterers don’t pay attention to it. They have better tools to choose the most efficient vessel like the owner-guaranteed charter party speeds and consumptions,” said Zachariadis.

He said owners are not stupid - they do not need a regulation to reduce their fuel bill; they can do the calculations themselves. Further, ships are not refrigerators. “You cannot rate their operational efficiency using simple indices such as EVDI, EEDI, EVI, EEOI etc,” he said.

So what is an eco-ship?

Zachariadis explained reduced fuel consumption comes from a good hydrodynamic hull form “being the most important aspect”, a proper size engine “larger than typical but derated” and a good propeller.

“The most important part of the hull for reduced resistance is the bow. For slow speed ships like tankers and bulk carriers’ a slim straight bow ‘titanic style’ seems best. My company applied the concept years ago to our bulbous bows and saved 7.5% in fuel consumption over the yard’s standard design, with a very minor deadweight penalty. Another 7.5% was saved by applying a larger engine, an extra cylinder,” he explained.

He said a super slow speed engine allows for a larger, thus more efficient, propeller . But slow speed engines don’t produce hot exhaust glasses, thus the boiler may need to be fired to produce the required steam, eliminating the larger propeller savings. The boiler consumption is substantial and usually ignored in the calculations.

He concluded: “In general, shipyards now pay more attention to their hull forms; we see many straight bow designs, albeit still a bit to full. Because of EEDI however they use small engines, which in reality increases consumption, and thus CO2 emissions, when the engine needs to run near 100% MCR to achieve the design speed.

“Owners should evaluate the efficiency of potential designs by requesting the total fuel consumption of the ship in various speeds and various drafts. As a minimum: slow / full speed at ballast, design and maximum drafts. Don’t forget to include the boiler consumption.”

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