Propulsion Technology for Polar Expedition Ships
Authors: Irgens Ole-Jacob , Kokkila Kimmo , Hänninen Samuli 
Published: October 2018

Abstract
The cruise industry is seeking new markets and products to trigger a growing customer base around the world. As the more traditional cruise ships have become bigger and more geared towards mass tourism in typical locations like the Mediterranean and the Caribbean, there has also emerged a need for smaller niche type of cruises, typically higher end and more exclusive. Exploration of the Arctic and Antarctic is exotic and is seen as the next step after the popular cruises to places like Alaska has become mainstream.
To enable the cruise industry to conquer Polar region a new generation of cruise ships is entering the market. A common feature for all of these is that they are smaller ships with more luxurious accommodation. Strong focus on safety, customer comfort along with sustainability and low environmental footprint are also all key drivers in this market. To achieve these objectives some of latest technology in terms of propulsion, power generation and distribution, navigation and digital solutions is critical. As per today more than 25 such expedition cruise ships are on order, most of which have been contracted in 2017.
Ensuring the safety, comfort and satisfaction of 100s if not 1000s of passengers and crew in such inhospitable regions is no mean feat. Through the experience and innovation in hip power management and propulsion systems some companies have become the leader in providing these type of solutions to the cruise industry. The past 25 years the leading companies have worked closely with ship owners, operators, designers and shipyards to develop the technical that is now setting the standard in the cruise industry.
Historically, naval architects have tackled these issues independently, working within rules developed by individual classification societies. However, the exhaustive harmonization work done in developing the IMO's new Polar Code has delivered a type of equivalence in structural and machinery specifications, as set out in the International Association of Class Societies Unified Requirements for Polar Class (PC) ships, which come into force on 1 January 2017.
Podded propulsion systems offer major safety benefits for ice-going vessels and has built a strong track-record across the sector, as demonstrated by the fact that it already satisfies IMO's Polar Code requirements and is available with PC notations suitable for a range of ice conditions. This level of confidence stems from past performance, with more than 60 vessels now in operation or ordered working in icy waters, including Pechora Sea, Kara Sea, Ob Bay, and Yenisei River.
In addition to ice-going ships, today, around 100 cruise ships are fitted with podded propulsion, including the world's largest such vessels - Royal Caribbean's Oasis class. In fact, due to better vessel maneuverability, improved passenger and crew safety, greater fuel efficiency and lower total cost of ownership, podded propulsion have largely superseded conventional shaftline propulsion in combination with rudder steering across the cruise market.
Given the strength demonstrated by podded propulsion in these distinct markets, it came as little surprise that PC6 classed Podded propulsion was selected for polar discovery yacht Scenic Eclipse-the world's first passenger vessel to be constructed explicitly to Polar Code standards-and for three Endeavor class ships which will be the world's largest expedition yachts with ice class. Before the end of 2017 Lindblad Expeditions Holdings, Inc. signed an agreement with Norwegian shipbuilder and ship designer Ulstein to build a new ice class expedition ship relying on podded propulsion system. According to recent news VARD Holdings Ltd. will build unique state-of-the-art LNG dual fuel electric hybrid icebreaker expedition vessel with the second highest icebreaking class Polar Class 2. When delivered, this ship equipped with pod propulsion will be revolutionary in its class. Taking all this into account, it is fair to consider the modern propulsion technology as the natural starting point for new generation cruise ships crossing polar and sub polar waters.