Brazilian towage group Starnav has selected Schottel RudderPropellers for a quartet of escort tugs to be built in Brazil.

The vessels concerned are being built at Detroit Shipyard in Itajaí, Brazil, the investment being part of Starnav’s aims to reach IMO 2030 and 2050 goals to reduce greenhouse gas emissions. Schottel Rudderpropellers will power the vessels, the first of which will feature its Sydrive-M technology from the start, the remaining three configured to be Sydrive-M ready.

Starnav's latest quartet will feature Schottel thrusters (Schottel)

Starnav’s latest quartet will feature Schottel thrusters (Schottel)

Schottel states the mechanical hybrid solution ensures lower maintenance costs and lower fuel consumption without the costly complexity of common hybrid technology. For Starnav, the quartet will offer more profitable and emission-reduced towing services and the contract strengthens its relationship with the German propulsion system manufacturer with 34 of the former’s vessels propelled by Schottel thrusters.

The 32m long, 11.6m beam ASD tugs will each be fitted with two type SRP 490 RudderPropellers, featuring 2.8m diameter fixed-pitch propellers developing 2,525kW each and delivering a bollard pull of more than 80t and speed 12.5kn. The Sydrive-M system is simple in its operation, adopting a mechanic connection between the port and starboard thrusters allowing the two to be driven together by one engine, for example during periods of low load. This results in reduced main engine running hours, lower maintenance and less fuel consumption. No additional electronic components are required and the system translates into three main operational modes for the tug master: light operation or free sailing mode, full thrust operation mode and firefighting mode. The first of the four vessels is scheduled to enter service with Starnav in 2022.

The IMO’s strategy in reducing greenhouse gases in the form of its 2030 and 2050 goals may seem a long way off but the fact that vessel owners such as Starnav have one eye on such future developments will no doubt indicate to shipyards, vessel designers and component manufacturers that the appetite from the top of the chain is there, including of course the desire for green operations by the tug operators own clients.

IMO’s challenge to maritime industry stakeholders to find, develop and integrate more energy-efficient solutions includes a set of toolkits such as the Ship Emissions Toolkit and Port Emissions Toolkit which provide practical guidance on assessing emissions and identifying fleet reduction opportunities.