Machinery: This technology group includes measures that improve the energy efficiency of main and auxiliary engines. These include measures such as auxiliary systems optimization, optimizing heat exchangers, waste heat recovery systems, electronic auto-tuning, batteries and other solutions.
Propulsion and hull improvements: Technologies in this group focus on improving the hydrodynamic performance of the vessel. This includes solutions that reduce the resistance of the vessel and/or also improve the propulsive efficiency of the vessel. Examples include measures such as propeller polishing, hull cleaning, PIDs (Propulsion Improving Devices), air lubrication and more.
Energy consumers: Consumers are equipment or devices that use energy when operated. Technologies in this group focus on minimizing the energy consumption by improving the device or optimizing the utilization of the device. Examples of measures in this group are frequency controllers, cargo handling systems, low energy lighting and more.
Energy recovery: Technologies in this group focus on capturing energy from the surroundings of the vessel and using or transforming this to useful energy for the vessel. This involves measures such as application of kites, fixed sails or wings, Flettner rotors, or solar panels.
Technical solutions for optimizing the operation: Technologies in this group focus on improving the operation of the vessel more than improving the vessel itself. The list of suggested measures includes both technologies and suggestions for best practice (without direct application of a technology). Measures in this group include trim and draft optimization, speed management, autopilot adjustment and use, combinator optimizing, and others.
Improving the energy efficiency of vessels means lower fuel consumption and reduced CO2 emissions. With this concept in mind, IMO adopted the Energy Efficiency Design Index (EEDI) – the first industry-wide global regulation of CO2 emissions.
The EEDI establishes the energy efficiency requirements of individual vessels in terms of CO2 emissions per capacity-mile, i.e. grams CO2 per tonne-mile. The EEDI for a given vessel is calculated by a mathematical formula which takes into account the vessel’s theoretical energy consumption based on the engines installed, measures to improve efficiency, and the vessel’s size and capacity. The lower the calculated EEDI for a vessel, the more energy efficient the vessel is deemed to be. The regulation mandates that the calculated EEDI for a given vessel should be below a required level. The limitations will gradually become stricter towards 2025. Calculation of the EEDI is mandatory for new ships over 400 gross tonnes of the following types and keel-laid dates:
Ships with conventional propulsion contracted after 1 January 2013 or delivered after 1 July 2015:
- Bulk carriers
- Gas carriers (including LNG carriers)
- General cargo ships
- Container ships
- Refrigerated cargo carriers
- Combination carriers
- Passenger ships (no required level)
Ships with conventional propulsion contracted after 1 September 2015 or delivered after 1 July 2019:
- Ro-ro vehicle carriers
- Ro-ro cargo ships
- Ro-ro passenger ships
- LNG carriers (new calculation method)
- Ships with non-conventional propulsion machinery contracted after 1 September 2015 or delivered after 1 July 2019:
Cruise passenger ships
The scope of the EEDI may be extended to include passenger ships (other than cruise ships with non-conventional propulsion machinery) and other ships with non-conventional propulsion machinery in the future.
Ships that are not propelled by mechanical means, platforms including FPSOs, and FSUs and drilling (regardless of propulsion), and cargo ships with ice-breaking capacity are exempt from the EEDI requirements.
The formula for calculating the EEDI is shown in more detail below: