Classification society DNV on Thursday (16 November) released a Maritime Impact report on the decarbonization of ferries. The following is excerpts from the article:
As shipping examines a range of options to reduce greenhouse gas emissions, recent technological innovations in the ferry industry have focused on electrification and battery power. DNV presents three key technologies driving the decarbonization of ferries.
With IMO decarbonization targets becoming more ambitious, and social and political pressure building, each sector of the maritime industry needs to examine the most practical and cost-efficient ways of reducing greenhouse gas emissions. For ferries, electrification and battery power are high on the agenda.
Electrification and battery power perfect fit for ferries
“Ferries are the perfect segment for electrification and battery power,” says Hans Eivind Siewers, Segment Director of Passenger Ships and RoRo at DNV. “Short, regular routes between the same ports makes it easier to charge regularly and reduces the need for large batteries.”
Three new technologies have emerged in recent years which are expected to have an impact on the ferries market. For all, the development has been facilitated by recent technological developments, most notably improvements in the energy density of batteries. Two of these innovations are based on hydrofoiling, an established technology which is making a comeback due to energy efficiency gains.
Hydrofoiling: Back to the future with Fast Foil Ferry
Hydrofoil technology – where a foil lifts the vessel up from the water as it gathers speed – was popular in the 1970s due to passenger comfort and high speeds, but this was eventually sidelined due to poor fuel and energy consumption. However, over the past few years, advancements in high strength and lightweight composite materials, gains in hydrofoiling technology and – most importantly – increases in the energy density of batteries have reopened the door to this technology.
Collaborative innovation: Developing a fully electric Fast Foil Ferry
In 2020, Kitsap Transit (a public transit agency serving Kitsap County, Washington, part of the Seattle metropolitan area), Foil Ferry LLC (a collaboration between Anacortes-based Bieker Boats and Seattle naval architecture firm Glosten) and Washington Maritime Blue received a Federal Transit Administration innovation grant to develop a proof-of-concept design for a fully electric Fast Foil Ferry. This has led to the delivery of a preliminary design for a high-speed hydrofoil passenger ferry, aided by DNV-led studies around shoreside infrastructure and permitting requirements and economic and environmental impacts.
Decarbonization just one advantage of Fast Foil Ferry
“These ferries use around one-third of the energy of conventional fast ferries and have zero local emissions,” says Cassidy Fisher, Programme Director of Washington Maritime Blue, which is coordinating the Fast Foil Ferry project. “They produce negligible waves as the hulls fly above the water’s surface. This is important for protecting sensitive shorelines such as those along Rich Passage, Washington, which makes up a significant portion of the Bremerton–Seattle route.”
With a cruising speed of 30 knots (around 55 km/h), the ferries have a range of about 30 nautical miles. This means they will be able to complete one full round trip on the proposed Bremerton to Seattle commuter route without recharging.
Financial benefits make the business case for Fast Foil Ferry
Besides the extensive list of advantages, including reduced motion compared to non-foiling hulls, providing passengers with a more comfortable ride, reduced noise, and the hope that increased ferry traffic will result in fewer cars on the roads of Washington State, the Fast Foil Ferry will also deliver significant savings to its operators.
“We have estimated a 35% reduction in annual operating costs compared to conventional diesel-powered ferries, mainly due to energy savings, although this depends on the price of diesel,” continues Fisher. “Alongside the decarbonization benefits, this is a strong business case and removes any significant barriers to further development.”
The project is aiming to secure another USD 4 million in federal funding so it can advance and complete the design development stage, while full-scale trials, construction and deployment, and the development of shoreside infrastructure will require another USD 18 million in funding.
From LNG to battery power
In Uruguay, ferry operator Buquebus is preparing to start operating the largest battery-powered ship in the world. Currently under construction at Tasmania-based shipbuilder Incat, the 130-metre ship will have a battery capacity of over 40 MWh, almost four times the capacity of any battery-powered vessel constructed before.
Following the success of the DNV-classed HSC Francisco Papa, Incat’s first LNG vessel delivered to Buquebus in 2013, the new DNV-classed vessel was originally planned to run on LNG. This was switched to electric/battery propulsion after Robert Clifford, founder of Incat, showed Buquebus his plans for a new electric/battery-powered ship.
“Our President Mr. Lopez Mena asked Incat if it was possible to use the electric propulsion on our future vessel,” explains Gerardo Babini, Technical Manager, Buquebus. “After a couple of weeks of weight and speed calculations, Incat came back to us and said it would be possible.”
The future of ferries is battery-powered
While the Buquebus ferry is very different in design to the two hydrofoil vessels, all of these technologies showcase the key role that electrical/battery power can play in the decarbonization of shipping. This is likely to increase, particularly in the ferry industry, as battery technology develops even further.
“These technologies are all extremely exciting and impressive, but we can expect so much more from battery power over the next ten years,” says Hans Eivind Siewers. “Improvements in density will extend ranges, opening up longer routes and reducing the reliance on scarce carbon-neutral fuels. This will contribute greatly to shipping’s quest to reach net-zero by 2050.
Note: DNV’s full Maritime Impact report on ‘Decarbonizing ferries: Technological innovation and electrification’ can be found here.
Photo credit: DNV / Incat Tasmania
Published: 24 November, 2023