Breaking the ice: opening up the Arctic ocean

The noise is constant. Every surface shudders so violently that a glass of water set down on a table is emptied in seconds by the motion. Aboard the world’s largest and most powerful icebreaker, it is impossible to ignore that you are thundering through Arctic pack ice every inch of the way to the North Pole.

The 50 let Pobedy (50 years of Victory) is capable of continuously smashing through pack ice 2.3m thick at a speed of three knots for days. Ice five metres thick does not present a problem for the Victory, but occasionally the ship comes to a juddering halt as it hits a pressure ridge – an accumulation of ice that can be up to 15m thick. The ship slowly reverses in its track, building up speed as it moves forward to repeatedly ram the ice until it finally relents.

Captain Dmitry Lobusov doesn’t hesitate when asked what qualities an icebreaker captain must have. “Confidence,” he replies. Despite the goliath capability of his vessel and a decade of experience, Lobusov admits that entering the ice always makes him nervous. “No vessel can be complacent out here,” he says. “The ice is always dangerous.”

At 159.6m long, 30m wide and with a draught of 11.08m, the 50 years of Victory has a displacement of 25,840t. The hull is 48cm thick with two layers separated by water ballast. The outer hull is argon-welded armour steel 46mm thick, with a 5-7mm plating of stainless steel positioned at the level where the hull meets the ice, known as the ice-belt. The weight and strength of the Victory is key to its icebreaking ability. Like all icebreakers, rather than slicing through, the bow of the Victory rides up over the frozen sea surface so that its immense weight bears downwards to crush it beneath. The bow is shaped like the back of a spoon, enabling it to easily ride over the ice. However, the main reason the Victory holds the highest possible ice class (LL-1) is due to its formidable propulsive power.

Descend the 12 decks of the Victory (four of which are below water) and it is striking how temperature increases steadily deck-by-deck. This could have something to do with the two pressurised KLT-40 nuclear reactors on board. In a small room containing nothing but a bright red phone on a small desk, it is possible to peer through a tiny lead-lined window at the Victory’s reactors in their shielding of steel, high-density concrete and water. Together they generate an astonishing 75,000hp. The cooling fluid from the reactors is used to produce steam at 310°C, which creates the one kilovolt (kV) DC needed to rotate three 20m-long propeller shafts. Each reactor weighs 160t and contains 245 enriched uranium fuel rods. This represents 500kg of uranium isotopes per reactor when fully fuelled. Even when breaking through the thickest polar ice, maximum consumption is just 200g per day, meaning the Victory only needs to refuel once every five years.

As the largest of six ‘Arktika’ class nuclear powered icebreakers operated by the Russian Atomic Fleet, Rosatomflot, the engineering of the Victory is impressive, but dated. The icebreaker came into service in 2007, but was launched in 1993 and built from 1980s design. The extended delay was caused by the collapse of the Soviet Union.

In contrast, icebreaker engineering has historically always been at the forefront of maritime design and innovation. The evolution from 1,000hp steam-powered icebreaking vessels of the 19th century to the modern, multi-purpose icebreaker fleets of today has needed inventive solutions, many of which have later become standard across all forms of shipping. Azimuth thrusters are a propulsion mechanism in which the propeller is able to rotate 360° around the vertical axis, providing propulsion, steering and positioning thrust all in one. Throughout the early 1990s, the azimuth thrusters designed for icebreakers were housed within pods and the propeller connected directly to the shaft of an electric motor, also contained within the pod, which powered the unit. This arrangement, known as an Azipod, was considerably more efficient, both mechanically and hydrodynamically. By the end of the decade, 11.4MW Azipod units were retrofitted to Finnish oil tankers and routinely incorporated into the design of some of the largest cruise ships in the world.

Other technology innovations driven by icebreakers include specialist low-friction hull coatings that are simultaneously ice-​resistant, trimming tanks in the bow and stern which enable longitudinal or transverse tilting when water is pumped between them, and air-bubbling systems, in which pressurised air is released from nozzles below the waterline to lubricate the hull and reduce friction.

In September 2016, the Finnish Transport Agency took delivery of the icebreaker Polaris. With propulsion power of 21,500kW, capable of breaking ice two metres thick at a speed of two knots, it is the most powerful icebreaker in the Finnish fleet. It is also the world’s first icebreaker to be fuelled by liquefied natural gas (LNG). Designed by Finnish company Aker Arctic Technology Inc and partly funded by the Trans-European Transport Networks (TEN-T) programme of the European Union, Polaris features two nine-cylinder and two 12-cylinder four-stroke dual-fuel engines that can use both low-sulphur marine diesel oil and LNG.

The ship can carry 800m3 of LNG, stored in two vertical tanks, giving it 10 days’ autonomy before needing to refuel or switch to diesel. “This works in the specific case of Polaris, which will operate close to the coast, but the more usual autonomy requirement of 30 to 45 days will be difficult to achieve in clean energy,” says Mika Hovilainen, who has been a senior project manager at Aker Arctic for 10 years and worked on the Polaris concept development. Despite this, Hovilainen believes that more efficient icebreakers are of greater importance to the future than the use of alternative energies. “Our aim is always to design icebreakers that can complete the same tasks but with significantly less power,” he explains. “Efficiency comes first. We design to need as little fuel as possible and then we can try to combine that with the use of environmentally friendly fuel.”

The emergence of oblique icebreakers might provide the next big breakthrough in energy efficiency. The Baltika, which completed its final ice trials in March 2015, is the first icebreaker capable of manoeuvring ahead, astern and diagonally. With an innovative asymmetric hull, and using three 2.5MW azimuth thrusters, the Baltika can alter its angle of attack to clear a channel through the ice much wider than its 20.5m width. Previously, clearing a channel for tankers, which can commonly be 50m wide, had required two icebreakers or a double channel. When operating at its maximum angle of attack, the 76.4m long Baltika can clear a 50m channel through one-metre thick ice without needing the support of another icebreaker. Although the Baltika is still relatively untested, it is clear that oblique icebreakers can offer significant savings in fuel consumption as well as greater manoeuvrability.

The Baltika, like the Polaris, was designed by Aker Arctic, and both icebreakers are highly automated. Whereas the previous generation of vessels required crews of 50 or more, the Baltika needs just 24, while the Polaris operates with a crew of 16. Computerisation is most striking on the bridge of the new generation, where the IT is increasingly sophisticated. The availability of more accurate radar and ever faster satellite imagery has revolutionised route planning in ice conditions, a task which used to involve sending helicopters ahead to survey the ice.

So could completely autonomous icebreakers be on the horizon? Hovilainen thinks not. “Self-automated merchant ships are coming on the market, but it is significantly more complicated in ice than in open water,” he says. “It is necessary to recognise which ice presents the greater risk; it is not easy to read the ice pack. That is difficult even for crew.”

Finland has always been the traditional centre of icebreaker technology, and it builds over 60 per cent of vessels. They are employed to keep 23 different sea ports open during the six months in which the country’s entire coastline is barricaded by ice. However, the advanced technology of modern ships makes them extremely versatile and they can now be found year-round in all parts of the world, carrying out work as varied as laying deep-sea cables off the coast of Brazil, or drilling into the seabed of Alaska and the North Sea. Even in the familiar arena of the Arctic Ocean, ever greater diversity of icebreaker capability is demanded by a rapidly shifting physical and political climate.

According to Nasa, carbon pollution has resulted in a 13 per cent reduction in the extent of the Arctic Ocean’s perennial sea ice per decade since 1978. These dramatic changes present new opportunities, from the establishment of new and shorter intercontinental trade routes, to the access of untapped resources such as fossil fuels and high-latitude fishing grounds. Icebreakers are needed to escort shipping as well as other functions such as oil-spill response, seabed mapping, support and supply of remote communities, search and rescue, science and even tourism. Already the US Coast Guard has reported that the number of vessels navigating into the Arctic through the Bering Strait has doubled since 1998. As the race to exploit Arctic resources begins in earnest, icebreaker technology will be in ever greater demand.

“We have seen a real upsurge in interest in icebreaker construction,” says Klaus Dodds, polar regions specialist and professor of geopolitics at Royal Holloway, University of London. “An accessible Arctic doesn’t mean a safe Arctic, and just because the extent of Arctic sea ice is shrinking, doesn’t mean it isn’t still a hazard,” he points out.

Many Arctic nations have begun to hastily upgrade their icebreaker capability and Russia is leading the charge. In the summer of 2016, Rosatomflot launched a new nuclear icebreaker which, when it comes into service in 2017, will assume 50 years of Victory’s title of ‘world’s most powerful icebreaker’. At 173.3m long, 34m wide and with a draught of 10.5m, the Arktika will have a displacement of 33,540t. Powered by two RITM-200 pressurised water nuclear reactors, each generating 55MWe from 20 per cent enriched uranium-235, the Arktika will be able to generate 81,000hp. Two sister ships of this new LK-60YA icebreaker class, the Sibir and the Ural, have already been laid down and plans for an even larger LK-110YA class of nuclear icebreaker have been announced. Also under construction is the Viktor Chernomyrdin which, when it comes into service in 2017, will be the largest diesel-powered icebreaker in the world. With a displacement of 22,000t, it can produce 46,800hp.

This bolstering of the Russian nuclear and non-nuclear icebreaking fleet has caused a great deal of sensitivity among other Arctic nations about their icebreaker capability, particularly the US, which is noticeably lagging behind. It has just two polar-capable vessels, the Polar Star, a heavy icebreaker built in 1976, and the Healy, which is predominantly designed for scientific work. It is not surprising that the need for modern icebreakers is now seen by many in the US as a matter of national security.

Even non-Arctic nations consider these vessels’ significant price tag to be a priority investment. China announced in January 2016 that it would be embarking on its first domestically produced polar icebreaker. It currently operates the Xue Long (Snow Dragon), which was bought from the Ukraine in 1993. With a displacement of 21,025t and a single diesel engine producing 17,000hp, it can continuously break 1.2m thick ice at a speed of 1.5 knots. The new, as yet unnamed, ship will be able to break 1.5m thick ice at a speed of two to three knots.

Dodds believes that in addition to operational uses, the icebreaker has become a powerful symbol of national Arctic ambitions in many ways. “The Canadians have shown that icebreakers are invaluable in seabed mapping, which is of course crucial to claiming sovereign rights over continental shelves,” he says. “The Swedish see icebreakers as a good form of soft power, promoting science diplomacy to project itself as an Arctic contender. Then look at the work the Snow Dragon does. An integral element of China’s strategy in the Arctic uses the Snow Dragon to very publicly access all parts of the region.”

For Dodds, it is clear that the icebreaker is used to create a visual culture of the Arctic. “If you look at the published material about national Arctic strategies, ships with an icy backdrop feature strongly,” he says. “The icebreaker has become a tool to nationalise the Arctic.”