LNG Fueled Ships: Recent Technical and Regulatory Developments

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February 15, 2012

By Sean Bond, ABS Director of Environmental Solutions

The potential of LNG to be a ‘fuel of the future’ for the shipping industry is a subject we hear about almost daily. There is no doubt that LNG ticks the box in terms of emissions reductions compared to conventional fossil fuels. But the expansion of LNG as a fuel into the mainstream shipping industry throws up a combination of technological and regulatory challenges that the industry must address.

To some extent, this already is happening. ABS has provided insight over the past year on the drivers for adopting LNG as a fuel, examining the Classification issues of technology, safety and the regulatory framework, and we definitely see there is interest.

LNG as a fuel is not new. What is changing is the scope and scale of application as LNG as fuel grows beyond its traditional role on LNG Carriers and its use on a limited number of small ferries during the past decade.

Expanding the application to new vessels types in diverse configurations has created a need for construction and arrangement requirements as well as standards to maintain existing levels of safety in the shipping segments using the new fuel. That’s where we come in. As a Class Society our mission is to provide for the safety of life, property and the natural environment.

american bureau of shippingOn the regulatory front, the fact that LNG fuelled projects are moving forward for uses other than traditional LNG carriers means Class Rules have had to evolve ahead of global regulation. For example, while the IMO has issued Interim Guidelines on Safety for Natural Gas Fuelled Engines on Ships ABS has issued its Guide for Propulsion and Auxiliary Systems for Gas Fuelled Ships in May 2011, which incorporates elements of those guidelines as well as additional needed criteria not yet specified in the IMO Guidelines.

On the regulatory side, the next step will be to complete the International Code of Safety for Gas Fuelled Ships, but its completion and ratification are not expected before 2014. In the interim, Class will continue to support owners, designers and shipyards as they determine what the concepts will mean to them.

Having recognized a need not just for Classification Rules and their interpretation, but also for recognized standards supporting the application and use of the technology, the industry is making progress developing standards with the International Standards Organization on LNG bunkering.

Today, LNG fuels a fleet of more than 380 LNG carriers, most of which burn part of their cargo as fuel, and a further fleet of some 22 small LNG-powered vessels. , However, technical and other questions remain as to the suitability of LNG fuel for specific projects. As a result, concept designs and newbuilding plans must be assessed on a case-by-case basis depending on their intended operating profile, fuel availability, commercial feasibility and several other issues. As projects begin to be realized, project developers will better understand the usefulness of the concepts to their own circumstances.

Major issues include the question of LNG bunker supply and demand. LNG bunker suppliers rely on demand to develop the supply infrastructure, while operators and owners require a supply before investing in a vessel that relies on that supply. In addition, the costs of bunkering an LNG vessel are not necessarily known as there is not a large existing market for small volumes of LNG to be used on gas fuelled ships.

And as emission regulations for all ships continue to tighten, the cost and availability of alternatives to ordinary heavy fuel oil, including LNG, potentially will change over the coming decade. All of this has to be weighted against the relative capital expenditure among competing fuel type concepts.

In many ways, the questions around LNG fuel supply are similar to those for low sulphur fuel oil: How good is security of supply?, Where are the bunkering locations?, How good is the availability? and What is the cost? Theseare the same questions that were asked about today’s commonly used fuels before they became widely accepted.

Regarding the fuel itself, owners also need to understand both its properties and handling. LNG is a mixture, not a homogenous product. It has different compositions, which result in variable properties.  The energy in each cubic meter and the methane number can impact the volume of fuel required and the way the fuel is handled as well as engine performance.

Other items to consider include the power profile of the vessel and to what degree it operates below or at maximum power, an issue engine manufacturers already are addressing.

This does not means the technology issues cannot be overcome. Instead, using LNG as a fuel becomes an issue of design and suitability on a project-by-project basis rather than a one-size-fits-all solution.

To address these issues, ABS has completed joint development projects with South Korean shipyards on large vessel designs and worked with owners including AP Moller-Maersk on the practical implications of LNG as a fuel on the current and next generation of large containerships.

In addition, Harvey Gulf International Marine has selected ABS as the class society for its two new dual fuelled LNG-powered offshore supply vessels being constructed at Trinity Offshore LLC for operation in the Gulf of Mexico.

Projects like this reinforce the argument that a move toward LNG as fuel could happen more quickly than has been anticipated. If we start to see positive operational results and compelling economic results on early projects, the move towards LNG fuel could come quickly.

For ships operating mainly in the IMO’s ECAs, LNG could be a very attractive option, and here we are talking about as soon as 2015 and 2020 or 2025, depending on how the IMO judges low-sulphur fuel availability. That in turn could lead to a ramping up of bunkering infrastructure, further strengthening the argument in favour of LNG.

Of course, this too will have its consequences. Training – and who will train the crew who will be handling this bunker fuel – is an important issue which needs to be addressed. The ISO bunkering standard mentioned above will help, and ABS is also developing training resources around this issue, but this is something the industry should take note of.

The success of the LNG industry in training crews to handle the product safely and in increasing ship size as demand has grown shows these challenges can be overcome. How LNG as a fuel works in this new environment is a somewhat different question. With many more gas-powered vessels in operation, the level of risk potentially is increased, so these risks have to be addressed and mitigated.

The use of LNG as fuel by the mainstream shipping industry is a journey rather than a destination. The role of ABS has remained the same since its founding 150 years ago; to promote the security of life, property and the marine environment, in particular when the maritime industry embarks in a new direction.

Sean Bond is Director, Environmental Solutions within the European Division of ABS.  Sean is a Graduate of the University of Michigan with a degree in Naval Architecture and Marine Engineering.  He joined ABS in 1989 as an Engineer in the Paramus, New Jersey office. Since then Bond’s ABS career has involved working in New York, Pusan and London in increasingly senior engineering positions. He has experience in rule development, design review and classification of various ship types, and accumulated specialist knowledge in the classification of tankers and gas carriers in particular. His current position, as Director, Environmental Solutions, involves close contact with the maritime industry throughout Europe, serving as a link between new environmental technology, emerging industry needs and environmental related developments in ABS.

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