*Technology and energy efficiency
Ballast water treatment technologies
Many ballast water treatment systems are now available on the market and, with ratification of the IMO Convention awaiting, ship owners have an excellent opportunity to evaluate how these systems perform before the Convention enters into force. The careful selection of a treatment system is furthermore important in order to ensure that the system meets the ship-specific requirements, such as ballast water capacity, power limitations and the integration of control systems. Another important advantage is the opportunity to gain insight into the manufacturer’s commercial reliability, support network and quality of supply capabilities. The technology used will depend on the vessel type, trading pattern, vessel size and design. However, all ballast water management technologies involve a filtration process which separates particles from the water flow using membranes and hydro cyclones. The filtration measures are usually easy to install and maintain, and are often necessary to save sensitive components down the line.
SOx reduction technologies
The revised Annex VI to MARPOL 2008 regulates the SOx emissions from ships, mainly by setting a limit for the sulphur content of marine fuel oils. Within specified ECAs, the sulphur limit will be even stricter than MARPOL Annex VI. Based on a review of existing marine engine technology and expected technology developments, ship owners currently mainly have two choices if they wish to continue sailing in ECAs after 2015: install an exhaust gas scrubber or switch to low sulphur fuel including LNG. An exhaust gas scrubber can be installed to remove sulphur from the engine exhaust gas using seawater or freshwater and/or chemicals which are pumped through the scrubber. Scrubbers can be retrofitted to ensure ECA compliance for existing ships, although there is still some uncertainty about the consequences of scaling up such installations for large diesel engines. Low sulphur fuel options will realistically be either expensive distillates or LNG, the latter in practical terms being an option mostly for newbuildings. For newbuildings from 2016 onwards and operating in an ECA, the NOx requirements add another layer of complexity due to possible technical incompatibility between SOx and NOx solutions.
NOx reduction technologies
NOx emissions are regulated through the revised MARPOL Annex VI 2008, which puts a limit on the specific emission from marine engines as a function of the revolutions per minute (rpm). The regulation applies only to newbuildings and is divided into three tiers based on the date of construction and on the operational area. Vessels with keel-laying dates after January 1, 2011 need to comply with Tier II requirements; these can easily be met by engine tuning by manufacturers. After January 1, 2016, newbuildings intended for operation in ECAs will have to meet Tier III requirements, which will require more drastic action. Feasible solutions such as: Exhaust Gas Recirculation (EGR), Selective Catalytic Reactors (SCR), Water injection – Humid Air Motors, (HAM)/Water in Fuel (WIF) and LNG Regardless of a price premium of 15-20% compared to conventional engines, LNG fuel will become more relevant in the coming years for reasons related to both economies of scale and estimated lower fuel consumption.
Energy efficiency and CO2 reduction technologies
The first formal CO2 regulations were adopted by the IMO in 2011. As discussed in the previous chapter, these comprise the EEDI and SEEMP, both of which will enter into force on January 1, 2013. By setting increasingly stringent energy efficiency requirements for new ships, the EEDI is intended to stimulate the development of more energy efficient ship designs, thereby indirectly leading to reduced operational CO2/GHG emissions. The SEEMP, on the other hand, is designed to directly stimulate more energy efficient operational practices. Energy efficiency measures are different from other emission abatement technologies as they fulfill two purposes: they reduce fuel consumption and not emission directly, and they are (potentially) cost effective. The expected higher energy prices and corresponding fuel prices will increase the focus on development of more energy-efficient systems for ships. Ships built today may in the future compete with more efficient ships. The creation of various voluntary rating schemes for environmental performance, including CO2 performance, is providing tools that allow charterers and cargo owners to use only ships that satisfy their new and stringent requirements. Further, several technological measures will be increasingly used in the coming years. The options can be categorized into four groups such as Reduction in ship resistance, Increase in propulsive efficiency, Increase in power production efficiency and Reduction in auxiliary consumption.