MAN Diesel & Turbo designs and develops large-bore diesel engines that comply with the demands and regulations made to the maritime industry. We also cooperate with authorities, governments and international organisations on the development of new regulations to fulfil the goal of reducing exhaust gas emissions by realistic methods. The aim is to develop methods that are applicable and practical to ship operators, and which will maintain a high level of safety and reliability of the engines.
One of the future goals in the marine industry is to reduce the impact of CO2 emissions from ships in order to meet the coming stricter International Maritime Organisation (IMO) greenhouse gas emission requirements. Two CO2 emission indices are being discussed at IMO, an ‘Energy Efficiency Design Index’ (EEDI) and an ‘Energy Efficiency Operational Indicator’ (EEOI). The EEDI is used to evaluate the engine and vessel design and the EEOI is used to guide the operator in developing best practices on board.
The goal is to design future ships with a design index to be stepwise reduced in the period from 2012 to 2018 to a maximum level of possibly 70% compared with the 100% design index valid for average designed ships of today.
One way of obtaining higher system efficiency, and thus lower fuel consumption and CO2 emission, is the use of Waste Heat Recovery Systems (WHR) in conjunction with the two-stroke main engine. MAN Diesel & Turbo is able to offer solutions for the whole range of WHR systems: Power turbine generator, steam turbine generator, and combined power and steam turbine generator systems.
IMO regulation of NOx and SOx emissions is already in place, and MAN diesel engines offer compliance with the strict IMO Tier 2 limits on the NOx emissions of the engine. Research work and service tests are being conducted to enable the MAN diesel engines to also comply with the much stricter IMO Tier 3 limits on NOx emission, which will be imposed for ships with keel laying from 1 January 2016, and which are to operate within designated NOx emission control areas.
SOx emissions can be reduced by removing sulphur from the fuel (use of low sulphur fuels) or, alternatively, using an exhaust gas scrubber system. Tests of scrubber systems have been conducted, and the results of long term service tests are being followed.