Powering towards greener seas with LNG

There is much to indicate that the name of the vessel fuel of the future is spelled LNG, and the future has already begun in Stockholm on 14 January 2013.

“Being first is pleasing, but it is also a challenge. Everything has to work from the start,” says Henrik Cars, Ports of Stockholm Port and Traffic Manager.

“It isn't the tank itself that is important; it's what you have in it that matters.” This is a good summary of status of shipping in the Baltic Sea in the 2012 winter season. On 1 January 2015 the new EU sulphur directive will come into effect. The new directive means that shipping companies will be forced to reduce the sulphur content of vessel fuels from 0.5 percent to 0.1 percent. Only vessels that meet these requirements will be able to call at Baltic Sea ports.

“Many shipping companies have probably waited in the belief that the directive would not be approved, but now it has been ratified and that is why there is a lot happening all at once,” explains Henrik Cars.

This means that the shipping companies have to decide on which strategy to follow. One alternative is to continue with heavy oils as a fuel, but to clean emissions more thoroughly using what are known as scrubbers.

“But I haven't seen emission purification that is completely efficient and so I believe that we will see a development where newly built vessels will run on Liquefied Natural Gas (LNG), with existing fleets switching over to using marine diesel,” says Henrik Cars.

Viking Grace - a unique environmental initiative

This is exactly the Viking Line strategy and Viking Grace, the world's first large passenger ferry to run on LNG, enters service in January. It is a spectacular vessel in many ways and the question is whether the passengers will notice the lack of smoke billowing from the stack, or the absence of soot on the decks.

Probably not, but today's environmentally aware travellers will surely appreciate the fact that the vessel emits around 25 percent less carbon dioxide and 85 percent less nitrous oxide than it would if it ran on oil, in addition to not releasing any sulphur or particle emissions into the atmosphere.

“It will not be possible to travel with a more environmentally friendly passenger ferry on the Baltic Sea,” says Tony Öhman, Viking Line Marine Operations Manager.

LNG meets the environmental targets

LNG is a significantly cleaner fuel than oil, but it is still a fossil fuel and so is non-renewable. AGA, the supplier of the liquefied gas, believes that LNG can be a bridge to running on renewable biogas in the future. The current problem with biogas is that the amounts required over the long-term are not being produced.

“There is no inverse reciprocal relationship between natural gas and biogas. Both will be needed in the future mix of different fuel types. On the contrary, there are good examples to indicate that natural gas can be a bridge towards the increased production and use of renewable energy sources, such as biogas. Until biogas and other renewable fuels are available in sufficient quantities, LNG can be used to meet our environmental targets,” says Carl-Lennart Axelsson, LNG Marketing Manager at AGA.

For Tony Öhman at Viking Line the choice of fuel was fairly obvious, despite the fact that it will initially be more expensive than running on oil.

“If we were to continue to use oil we would need to have two or three purification facilities aboard the vessel to clean up the emissions to meet the future environmental requirements. That is why we opted for LNG, a cleaner fuel that meets the requirements,” explains Tony Öhman.

Can the older vessels be converted to run on LNG?

“No, that is not possible. Instead we will switch to using marine diesel,” states Tony Öhman.

New reliable bunkering solution

Viking Grace is some way from being the first vessel to run on LNG. The fuel is a well tested product in the shipping industry, but Viking Grace is the first large passenger vessel to run on LNG. This has also led to many companies around the world following Viking Line’s work on Viking Grace with great interest.

But it is not just the shipping company that is a pioneer. Ports of Stockholm also believes it is exciting and challenging to be involved at the forefront of the development. This places demands on infrastructure, regulations and procedures over both the short and long-term. Ports of Stockholm must also develop solutions for a future where more and more vessels will run on LNG.

As this is also an area where there is no well-trodden path to follow, Ports of Stockholm has worked together with Viking Line, AGA and the appropriate government agencies to develop regulations and procedures.

The vessel was built in Finland, but the gas will come from Norway and be transported to the newly built AGA LNG terminal at Nynäshamn. From there the fuel will be transported daily by three tanker trucks to Frihamnen and Loudden, where it will be transferred to a bunkering barge that will then refuel Viking Grace at the quay at Stadsgården. The fuel provided by the bunkering barge will be more than enough to power the vessel to Turku and back.

Working towards a long-term solution

When this development gathers momentum, Henrik Cars says that the provision of natural gas using tanker trucks will not be sufficient.

“When volumes increase, and more customers demand provision of LNG at our ports, we will have to find other solutions,” explains Henrik Cars.

Tanker vessel delivery of LNG to Kapellskär, Stockholm and Nynäshamn is one viable option.

Another issue is how to bunker the fuel at the ports. This is a matter of finding sustainable and long-term solutions and is an effort that is being tackled in different ways using several approaches. Not least through the participation of Ports of Stockholm in an EU project, together with six other Baltic Sea ports, where this issue is being discussed.

As always where fuels are concerned, safety is an important issue. Aboard Viking Grace the tanks are located outdoors at the stern of the vessel. If the gas comes into contact with air it rises, as the gas is lighter than air, and this allows the gas to be vented away. In cooled form the pressure in the tanks and pipes is low, but the tanks and pipes are double-mantled so that no gas can leak out. An advanced gas monitoring system detects any leakage and immediately shuts the system down.

“If a leak should occur, the system will switch directly to running the vessel on marine diesel,” explains Tony Öhman.

Liquefied Natural Gas is a tried and tested product that has been handled safely for decades. There are also strict regulations governing the design of the land-based cisterns and tanks. The liquefied gas is considered to be free from toxins and odours and is also non-corrosive. LNG is also difficult to ignite, partly due to its low temperature, but also because the natural gas needs oxygen to burn. As there is no oxygen in the cisterns and tanks, any outbreak of fire cannot spread in the containers.

The environment wins

Henrik Cars at Ports of Stockholm informs that a Norwegian shipping company is also now building a ferry that will run on LNG and operate Baltic Sea services within a few years. He sees the environment as the greatest winner when the new sulphur directive is introduced.

“For that reason it would have been better if the new sulphur directive came into force at the global level and not just in the Baltic Sea and North Sea. It would have been better for the environment and it would also have created similar conditions for shipping the world over,” states Henrik Cars.

“It is naturally difficult to be leading the way, but at the same time this can also turn out to be a major competitive advantage once the rest of the world begins to follow us,” concludes Henrik Cars.

Read more about LNG and LNG bunkering at Ports of Stockholm