International Maritime Organisation

Whether we like it or not, there is no avoiding the fact that the modern world is utterly dependent on motorised transport systems that run largely on fossil fuels. Moreover, it is also inescapable that the use of fossil fuels carries an environmental burden. An engine burning fossil fuel will emit a quantity of greenhouse gases (GHGs), principally carbon dioxide (CO2), and these emissions are now widely accepted as being significant contributory factors towards global warming and climate change.

Carbon emissions and fuel efficiency are directly linked. Less fuel consumption means smaller GHG emissions. Shipowners have always sought to minimise their fuel costs for commercial reasons, as fuel represents a significant proportion of their total voyage costs. Their methods have included using the shortest, safest and, therefore, most environmentally-sound routes between ports; economies of scale (the largest container ships being built now hold approximately 12,000 containers as opposed to 5,000 in 1990); and optimisation of hull design, engine technology and propeller design.

Improved design and efficiency

In recent decades, improved hydrodynamics in vessel hull design have brought reductions of between 2 and 4% in fuel consumption. More advanced propulsion systems and, in particular, propeller design have realised similar reductions. Better engine efficiency has resulted in even larger reductions. A new engine with the same power output consumes about 10% less fuel than its predecessor installed ten years ago. Of course, the long operational lifetimes of ships, on average about 25 years, does mean that the emission benefits associated with such new technology take a long time to achieve their full effect.

Since the adoption by IMO of air pollution regulations for international shipping in 1997 (now under revision), which included a ban on ozone-depleting substances, the Organization has engaged in further discussion on ways to reduce emissions from ships. An IMO study into GHG emissions from ships was undertaken and, in May 2000, the Organization decided to also prohibit the use of perfluorocarbons (PFCs) onboard ships. PFCs have extremely long atmospheric lifetimes (in excess of 5000 years) and possess high global warming potential.

Since then, and in support of a 2003 IMO Assembly resolution – A.963(23) on IMO Policies and Practices related to the Reduction of Greenhouse Gas Emissions from Ships – the Organization has been actively engaged in the development of a GHG Indexing Scheme for ships. Interim guidelines for this purpose were approved in July 2005 to establish a common approach for trials to enable shipowners to evaluate the performance of their fleet with regard to CO2 emissions. As the amount of CO2 emitted from a ship is directly related to the consumption of bunker fuel oil, CO2 indexing will also provide useful information on a ship’s fuel efficiency.

It has already been observed from such trials that identical ships in seemingly similar trades produce diverse results; the difference may result from different weather conditions or from operational differences concerning the specific utilisation of individual ships involved in the trials. Issues such as the length of time spent waiting in port areas, the length of ballast voyages, whether the ship is fully laden or not, can all make a difference.

As a result of IMO’s and the shipping industry’s efforts, a number of areas have been identified in which there is considerable potential for the further reduction of CO2 emissions from ships, such as optimisation of hull shape, hull maintenance, propeller design and maintenance, fuel choices, machinery monitoring, ship-routeing considerations including speed reduction, and optimising vessel trim, engine performance, propeller pitch and rudder angles.

Continual commitment to reductions

We continue to examine such options because it has been recognised and agreed that climate change caused by GHG emissions from burning fossil fuel is a steadily growing concern for most countries, and that the threat from global warming is far too serious to be ignored. Therefore, shipping, although already an environmentally- friendly and fuel-efficient mode of transport, must take further action and, in 2006, IMO adopted a work plan with timetable for future work on GHG reduction. We also agreed that the Organization should maintain its leading position in developing GHG strategies and mechanisms for international shipping and cooperate closely with other relevant UN bodies to avoid unilateral action on a global, regional or national level.

Currently, we are engaged in a comprehensive review to assess the wider impact of all the various options for reduction of air pollution proposed in connection with the revision of MARPOL Annex VI, and in a thorough updating of the 2000 IMO Greenhouse gas study.

In the Organization’s endeavours to achieve emission reductions, it is important not only to remain focused on the desired goal, but also to ensure that improvements in one area are not compromised by negative impacts in others. It is, therefore, essential to take a holistic and inclusive approach, to understand the “big picture” and to find balanced and workable solutions that achieve a positive net effect for the global environment.

These issues have to be tackled at the truly international level and, for shipping, that can only mean through IMO, which is the Specialized Agency of the United Nations with a specific mandate for creating the international regulatory framework for the safety, security and efficiency of international shipping and for the protection of the marine environment from ships. It is unquestionably the proper place for these matters to be resolved, both for reasons of principle and for practical considerations.

What is often overlooked in any discussion about overall levels of GHG emissions from shipping is that the total amount of shipping activity is not governed by shipping itself, but by global demand for shipborne trade. There is no doubt that shipping is a clean, green, environmentally-friendly and very energy-efficient mode of transport. Although, overall, it is only a small contributor to the total volume of atmospheric emissions, nevertheless, significant reductions in harmful emissions from ships and increases in fuel efficiency have been achieved over recent years, and this work must and will continue to be a high priority for all stakeholders.

That is why I was personally delighted that the IMO Council selected our response to current environmental challenges to take centre stage this year in the theme for World Maritime Day, and to be a centrepiece in a host of other activities and initiatives, forming part of a concerted action plan that we have been undertaking to educate people, increase their awareness about the true, and deteriorating, state of the planet, and help us all to become responsible citizens, in its fullest sense.

W: www.imo.org