Ro-Pax

FEATURE | Filipino shipbuilder embarks on wave-powered trimaran ferry project

Baird Maritime

A new technology demonstrator vessel that promises low-emission sailings with the help of ocean waves is currently being built at a shipyard in the Philippine province of Aklan.

Under a PHP76 million (US$1.59 million) project funded by the country's government through the Department of Science and Technology (DOST), shipbuilder Metallica Marine Consultancy (MMC), Aklan State University (ASU), and local regulatory body Maritime Industry Authority (MARINA) are working on a hybrid trimaran vessel that they expect will later see full operational use as a Ro-Pax ferry on routes in the Western Visayas and other nearby regions.

Once completed, the vessel will be capable of transporting up to 100 passengers, four vans, and 15 motorcycles on each sailing. It will also utilise a specially engineered hull design that the DOST said will not only greatly reduce the risk of capsizing, but will also enable the vessel to withstand harsh environments in the open sea, particularly along the inter-island shipping lanes found throughout the Philippines.

Multiple innovative technologies

Perhaps the most noteworthy feature of the new vessel will be its propulsion system, which the project partners said will include a traditional diesel engine and a system that will use ocean waves to generate propulsive power. Under the latter system, wave energy-powered double action hydraulic pumps will be integrated in the vessel's outriggers. The mechanical movements in these pumps will then be converted into electrical energy that can be used to provide additional power to waterjets fitted with independent-drive systems.

The DOST added that the more waves that the vessel encounters, more power will be produced, thereby making the vessel itself more energy-efficient. The diesel engine will then serve mainly as a backup.

The trimaran ferry under construction at Metallica Marine Consultancy's shipyard in New Washington, Aklan (Photo: DOST/Aklan State University)

The vessel will also be fitted with a semi-independent hydro-suspension system to lessen heave action and to reduce drag, which would otherwise be detrimental to efficiency.

To further reduce emissions especially when the backup diesel engine is in use, the vessel will utilise an exhaust gas filtration and aftertreatment system.

"ASU invited us in 2017 to collaborate with them on this project," MMC owner Jonathan Salvador told Baird Maritime. "This was in fulfillment of a request made by the DOST to local organisations in 2013 to submit recommendations on R&D projects centred on innovative technology."

Salvador added that MMC was selected partly because ASU and the DOST saw that two of the company's earlier newbuilding projects were already in operation on two inter-island routes. Both were built at MMC's facilities in New Washington, a small coastal town just outside Aklan's capital of Kalibo.

Salvador further claimed that a trimaran design was more ideal for demonstrating this new technology compared to a monohull ferry.

"Our analyses revealed that a trimaran would possess improved hydrodynamics over a monohull and can ensure fuel savings of as much as 40 per cent. We therefore expect the propulsion arrangement to enable the ferry to comply with EU Stage V regulations."

The first of many

Construction officially began with the vessel's keel-laying in December 2018 and was originally scheduled to be completed in early 2020. However, a devastating typhoon that swept through the area in 2019 and the subsequent Covid-19 pandemic forced MMC and ASU to repeatedly adjust their schedule in addition to having to operate with a skeleton workforce at the New Washington yard. The partners now expect to carry out a period of sea trials spanning three months within this year.

Salvador has emphasised that, even with its already innovative technology, the ferry will merely be the first in a series of locally-built passenger vessels that will operate on the same principle of wave-assisted propulsion.

"Our long-term goal is to make sure that more and more of the country's coastal provinces will have their own inter-island shipping companies," Salvador told Baird Maritime.