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Grace on the waves

It took 20 years to get a new cruise ferry into service between Finland and Sweden, but it was worth waiting. Viking Line’s Viking Grace is no ordinary ship: it’s the world’s first passenger ferry to run on liquefied natural gas.


TEXT: LENA BARNER-RASMUSSEN PHOTO: INDAV | UNDERWATER | JUKKA NURMINEN

The crew is going through the regular checklist in the engine control room. I’m whisked away and soon find myself standing outside a thick steel door, equipped with a safety lock. We are about to enter the engine room. I prepare myself for the strong smell of fuel. But, as I step in, I realize that there will be no assault on my nostrils. 

In a couple of minutes the engines will be started. Everything looks as it usually does in an engine room, except that this one is shining with cleanliness. And then there are yellow pipes running to the engines from the ceiling, supplying natural gas from the LNG (liquefied natural gas) tanks at the stern.
Apart from being the first passenger cruise ship in the world to run on LNG – and thus the most environmentally sound cruise ferry – Viking Grace is the stunning result of top-notch engineering and state-of-the-art design.

Viking Grace
There is hardly any vibration...



Polluted waters

The Grace operates between Turku and Stockholm; from her large windows you have a view of thousands of small islands scattered across the sea between Finland and Sweden. But although the scene is beautiful, there are perils lurking in the waters.

The Baltic Sea faces challenges, the biggest of which is eutrophication, caused when the water receives excess nutrients that stimulate excessive plant growth. This enhances algae bloom, of which some is toxic. During hot summers when algae flourish, it is even advisable to refrain from swimming in the sea. A more severe problem is their effect on the ecosystem.

The Baltic Sea is relatively shallow, about 55 metres on average, and is almost closed off from the Atlantic by the straits of Denmark, so any pollution that enters Baltic waters tends to stay there. Add to this its busy maritime traffic, inadequate coastal sewage treatment in some cities, and excess phosphorus from farming and industry, and you realise why this sea is among the most heavily polluted in the world.

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Gas is the future

Saving the Baltic Sea has become an acute concern for most people living by its shores. It was axiomatic that Viking Line’s new cruise ferry would comply with environmental legislation from the very start. Viking Line had been eyeing natural gas technology since 2004, but as the supply of LNG in the Baltic Sea was non-existent, they had to wait. In 2007 the drawings were taken out again and, this time around, things looked brighter.

When it became clear that LNG infrastructure would be built in Nynäshamn outside Stockholm, Viking Line took up long-standing negotiations with suppliers of LNG solutions. Wärtsilä won the contract.

There were also a lot of negotiations with the authorities on the LNG infrastructure. The project started in 2011 and, two years later, the ship was cruising on the Baltic Sea, so it has been a swift success.

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Sulphur emissions are being cut to protect the Baltic Sea’s fragile ecosystem.


Indisputable benefits

There are certain signs that you are travelling on a gas-operated vessel as soon as you see her. First of all, there is no smoke from the funnel. If you find soot on the deck, it has come from another vessel. And then there are the huge gas tanks at the stern.

Currently there are no cost savings from switching to LNG, but the environmental benefits are all the greater. The advantages over diesel oil are indisputable.

“The SOx emissions on Viking Grace are close to zero, and NOx emissions are at least 80 per cent lower. Particulates are negligible and CO2 emissions are 25 percent lower,” says Jukka Paananen, who led the sales project at Wärtsilä.

And there are substantial benefits in handling gas, which does not smell. This significantly improves the working conditions of the crew, who used to suffer from headaches on diesel vessels.

Gas is also clean. On this point Viking Line actually expects to save a buck or two, because the decreased need for cleaning machinery will cut the cost of maintenance. Wärtsilä has signed a five-year maintenance agreement, its first long-term agreement for a gas-operated vessel. The agreement covers the four Wärtsilä 50DF dual-fuel main engines, as well as the Wärtsilä LNGPac gas system’s safety valves. The overall target is to extend the intervals between maintenance and to ensure optimal operating efficiency and fuel consumption, thereby lowering operating costs.

Double-walled pipelines

Contrary to what action films tell us, gas does not catch fire easily. In order to ignite it in the engines, the Wärtsilä dual-fuel engines use pilot diesel injection.

“We all know what happens if you play with matches next to petrol. It will flare up. LNG in a cup doesn’t react to a match because the mixture of air and evaporated gas must be precisely right,” says Jukka Paananen.

Still, safety precautions are important. The gas in the tanks situated on Grace’s stern deck is transported in double-walled pipelines to make sure that leakage does not occur. The air space between the pipes is monitored with gas detectors.

The Viking Grace loads up on gas in Stockholm. The terminal is situated in Nynäshamn south of the city. There, the gas is loaded onto three trucks that transport it to a small vessel, the Seagas, anchored in Värta harbour close to downtown Stockholm.

When Viking’s ship arrives in the morning, she is greeted by Seagas and about 75 tonnes of gas are transferred. Her consumption is between 50 and 55 tonnes of gas per Stockholm-Turku-Stockholm round trip, so refilling is about six times a week.

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Green is nice

The crew is excited that the Grace is such a clean ship. When I talk to the people working on board, everyone – from the engineers to the restaurant waiters – seems to take pride in working on board the cleanest ship in the world.

The environmentally friendly solutions are not limited to the use of LNG. The environment has been considered in every single detail on board. The elevators, for instance, regenerate over 70 percent of their energy whenever they brake. The elevators are manufactured by a Finnish company Kone.

Wärtsilä supplied a sound-absorbing system to minimise the noise from the engines. This has been welcomed not only by Grace’s passengers but also by the thousands of people who spend their summers in island cottages along her route. These cottage owners also appreciate Grace’s hydrodynamic hull, which minimises wave formation.

The use of disposables is minimised in all of Grace’s eight restaurants. Naturally glass, paperboard, plastic, metal and biowaste is sorted. Whenever possible, the food served in the restaurants is locally produced.

On the bright day in late winter when I sailed, vast areas of white ice were spread out before my eyes. Hundreds of small islands were each covered with a thick layer of snow. The Viking Grace glided through the waters between them.

Every now and then came the sound of ice being crushed by the hull. A day could easily be spent just looking out of the windows. The archipelago outside Turku offers stunning views.

Compared to other passenger ships, there is hardly any vibration on board the Grace, thanks to the very low-pressure impulses generated by the propellers. As I sit in the champagne bar adjoining the fine dining restaurant, I can leave my glass of gracious yellow bubbles on the neat little table and trust that it will stay there.

Am I really at sea?
© 2018 Wärtsilä