Robert Allan-designed, Sanmar-built vessels become the world’s first large dual-fuel methanol-powered escort tugs, delivering up to 120 tonnes of bollard pull
KOTUG International has marked a major milestone in its sustainability strategy with the launch of two next-generation escort tugs, SD AISEMAHT and SD QWIY AANITSA SARAH, setting a new standard for low-emission towage operations in North America.
The vessels, which will operate in British Columbia in support of the Trans Mountain expansion project, have been designed by Robert Allan Ltd. and built by Sanmar Shipyards. At 44 metres in length, they are the world’s first large, purpose-built dual-fuel methanol-powered escort tugs, combining industry-leading escort capabilities with significantly reduced emissions. With 115–120 tonnes bollard pull, they will become among the most powerful escort tugs operating in Canada.
The vessels are equipped with dual-fuel engines capable of operating on diesel or methanol, enabling substantial reductions in CO₂ emissions when supplied with renewable methanol. Fully compliant with IMO Tier III standards, the propulsion system integrates advanced emission control technologies, shaft alternators and optimized energy management systems.
A mechanical cross-link system allows one engine to power both Schottel azimuth thrusters during transit operations. This innovation reduces fuel consumption, lowers engine running hours and improves overall efficiency — particularly during low-load sailing. The result is a smarter energy profile and reduced environmental footprint without compromising operational readiness.
In addition, advanced hull coating solutions help minimize underwater radiated noise, contributing to the protection of sensitive marine ecosystems along Canada’s West Coast, including whale habitats.
Together, these features position the vessels as a forward-looking response to the maritime industry’s decarbonization challenge — combining practical engineering with future-ready fuel flexibility.
Escort tugs operate at high power levels under demanding conditions. Integrating alternative fuels at this scale requires more than incremental adaptation — it demands systemic design innovation.
Kotug’s new escort tugs deliver:
- 115–120 tonnes bollard pull
- Full escort notation for tanker operations
- Dual-fuel methanol propulsion
- Cross-link thruster capability for optimized load sharing
- Integrated onboard power generation architecture
Rather than retrofitting existing tonnage, KOTUG chose to invest in purpose-built escort tugs optimised from the outset for performance, safety and sustainability.
This is not simply an alternative-fuel vessel. It is a high-performance escort platform designed to meet today’s operational requirements while preparing for tomorrow’s environmental standards.
Beyond their escort capabilities, the vessels are equipped with onboard oil spill response systems, including skimmers and recovered oil storage capacity, enhancing environmental preparedness in the Salish Sea. Dedicated firefighting systems further strengthen the safety and standby readiness available to all who navigate these waterways.
The launch of SD AISEMAHT and SD QWIY AANITSA SARAH carries a deeper meaning. The vessels are named in honor of the Sc’ianew First Nation, reflecting a partnership grounded in mutual respect, environmental stewardship and shared responsibility for traditional waters.
This collaboration symbolises a commitment to working alongside local communities in building safer and more sustainable marine operations. It also supports opportunities for engagement, employment and knowledge exchange — ensuring that progress in maritime innovation goes hand in hand with community inclusion.
For KOTUG, sustainability is not only about fuel and emissions. It is about relationships — and about recognizing that long-term operational success depends on trust, collaboration and shared values.
