Results From The World's Largest Arctic Ships and Advancements of Propulsion Technology

As a result of multi-year ice, shipping activity in Polar regions is growing. A completely new fleet of double-acting Arctic vessels has been developed and successfully proven their capabilities in the harshest environments. The size of Arctic vessels has also grown since the introduction of 172k Arctic icebreaking LNG carriers. Podded propulsion system is an attractive solution making these innovative ship concepts technically and commercially feasible. This paper will discuss practical experiences from Arctic LNG Carriers. ABB Marine & Ports has further developed Azipod® propulsion concepts to meet the demands of even larger icebreaking vessels with high power requirements. This paper aims to present the key design factors when developing propulsion systems for high power icebreaking ships. The largest podded drives for high ice class vessels have been up to 17MW. The new propulsion system has been developed to meet the market demand for a power range of up to 20MW. Scaling the range up offers considerable advantages for larger vessels. To mention a few the increased propeller size results in better hydrodynamic efficiency. Opportunities for increasing both the maximum bollard pull thrust and maximum over-torque both is another example. The unit will suit the highest ice class requirements such as IACS PC 1 and PC 2. The propulsion system utilizes different operating modes to meet the vessel’s operational needs. In difficult ice conditions the Azipod can be operated in specialized ice mode. This gives a very robust and reliable operation to dynamic load variations caused by ice. New technological solutions help ship owners to access opportunities in the Arctic regions by providing safe and reliable operation. The successful operational track record transporting LNG through NSR and Eastern Arctic offers proven propulsion solutions that can be used in Western Arctic energy projects as well. This paper will describe results from the world’s largest icebreaking vessels and the latest developments of the most powerful podded propulsion systems.