Modular Diesel-Electric Power For Coasters

Launched by Thecla Bodewes at its Kampen yard on the lower reaches of the River IJssel, the 7,000dwt Vertom Patty combines a special bow and hull form with a modular electric propulsion solution. Designated the Labrax-type, the project is testament to the unstinting drive by the industry in the Netherlands for efficiency gains in the small-ship sector.

Due to be phased into service towards the end of 2022, the 119m Vertom Patty leads a six-ship contract award to Thecla Bodewes, entailing delivery slots through 2023 and 2024 and into the opening stages of 2025. The Labrax 7000 template has been developed in conjunction with Groot Ship Design, originator of the energy-saving, proven Cross Bow concept, which is a feature of the new ships.

The launch of the lead vessel was immediately followed by official keel-laying of the second and third newbuilds at Kampen, the Vertom Cyta and Vertom Tomma.

Embracing two box-like holds with a total, competitive volume of 329,500ft³, accessed through hatchways that obviate any deck overhang length- or width-wise, the design is suited to working and transporting the gamut of short-sea commodities and products.

Computational fluid dynamics(CFD) optimisation of the hull form has been undertaken so as to achieve a fuel-efficient speed/power relationship, with performance keyed to the innovative use of a modular powering concept. The diesel-electric system consists of multiple generators, allowing the number of sets on-line at any one time to be adjusted in accordance with the vessel’s sailing and operating profile.

The arrangements have also been conceived in mind of future technical opportunities and the progression towards ever-lower environmental impact, by offering the possibility for adaptation to methanol-electric or hydrogen-electric propulsion.

Damen Marine Components was contracted to supply Optima nozzles, Van der Velden ‘plug-and-play’ piston-type steering gear, and Van der Velden Timon flap rudders for the Labrax 7000 series.

Vertom has also joined forces with Groot Ship Design in a subsequent project entailing a series of smaller vessels, of 5,600dwt, based on the same platform as the 7,000dwt type. An ensuing construction contract has been placed with Chowgule & Company in Goa, India, for six newbuilds to the 99m, diesel-electric design.

Each of the 5,600dwt multi-purpose cargo ships has been specified with four main generators, each of approximately 400kW, feeding two 650kW propulsion motors and a 400kW bow thruster. At ‘economical’ speed settings, achieving around 10 knots at design draught, operation will be on three generators.

The order in India involves completions between 2024 and 2026, and the vessels will incorporate a single hold of 260,000ft³ volume compared to the significantly larger capacity in the two-hold ships from Thecla Bodewes.

MAIN PARTICULARS – Vertom Patty