IMO regulations and winter navigation

Jorma Kämäräinen,
Chief Adviser, D.Sc.,
Finnish Transport and Communications Agency (Traficom),
Finland

IMO – the International Maritime Organization – is the United Nations specialized agency with responsibility for the safety and security of shipping and the prevention of marine and atmospheric pollution by ships. The most important IMO convention related to prevention of pollution of the marine environment by ships is the MARPOL Convention, which contains regulations for the control of pollution by oil, noxious liquid substances, sewage, garbage and emissions to the air. In order to improve the energy efficiency of ships and stimulate innovation in energy efficiency, the regulations based on the Energy Efficiency Design Index (EEDI) for new ships adopted by IMO as part of MARPOL Annex VI in 2011 entered into force on 1 January 2013. The EEDI value for a ship (the ‘attained EEDI’) is defined as an efficiency index, i.e. the ratio of the amount of CO₂ emitted per unit of work done for the society. The work done is defined for cargo ships as the ship deadweight times the ship speed.

Currently, IMO is planning to have new regulations for energy efficiency of existing ships in order to further reduce CO₂ emissions from shipping. IMO has agreed to impose regulations similar to the EEDI regulations to existing ships (Energy Efficiency Existing Ship Index, EEXI) and, in addition, new regulations on operational energy efficiency would also be applied to ships in order to reduce the carbon intensity of international shipping.

The most important short-term measure to reduce CO₂ emissions and energy efficiency from new and existing ships is to reduce their speed, which will require reduction of their maximum engine power. When new regulations are developed, it is important that certain minimum engine power level is maintained in order to secure safe operation of ships in adverse weather conditions. This is taken into account by developing guidelines for minimum engine power for ships for EEDI and EEXI regulations.

In addition to safety issues, it is important to guarantee level playing field in shipping, when new regulations for shipping are developed. In EEDI and EEXI regulations this is taken into account by adopting ship type and size specific regulations for ships, because different ship types have their specific design requirements and, generally, big ships have better attained EEDI and EEXI values than small ships. It is also important that specific design requirements of ships designed to carry special cargoes or operating in special environmental conditions are taken into account. Ships designed to sail safely in ice conditions, i.e. ice-classed ships, is a good example of the latter case.  Many ports in the northern Baltic Sea area are ice covered in winter and therefore ships sailing regularly in this area have an ice class. Fuel consumption and CO₂ emissions of ice-classed ships are higher than those of ships designed for sailing in open water only. The main reason for the higher fuel consumption is that the hull form and the propeller of ice-classed ships are less optimal for the operation in open water, as they must be strengthened for the operation in ice conditions. In addition to the increased fuel consumption in open water, ice-classed ships consume also much more fuel when sailing in ice covered waters compared to sailing in the same area in open water conditions. Due to higher lightweight caused by ice strengthening of the hull of the ship, ice-classed ships have a smaller deadweight, compared to their displacement than ships of a similar displacement designed for sailing in open water only, which has an impact on the attained EEDI and EEXI.

In order to ensure a level playing field between ice-classed ships and ships designed to sail only in open water conditions, the higher fuel consumption and the special technical design requirements for ice-classed ships have been compensated in the EEDI regulations by adopting three correction factors for ice-class ships for calculation of the attained EEDI. These correction factors allow installation of more engine power for ships belonging to certain ship types than for ships without an ice class and they also take into account the special design requirements of ice-classed ships. It is anticipated that the special design requirements of ice-classed ships and higher fuel consumption when sailing in ice conditions would also be taken into account for calculation of the attained EEXI and in the new regulations on operational energy efficiency in order to ensure the level playing field between ice-classed ships and ships not having an ice class.

More and more regulations are adopted for international shipping by IMO. It is very important that the balance between safety of shipping and environmental regulations is maintained as well as the level playing field between ice-classed ships and ships designed to sail only in open water conditions, when new regulations are developed.

Email: jorma.kamarainen@traficom.fi

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