Energy Efficiency Technologies Information Portal

Machinery

Propulsion and Hull Improvements

Energy consumers

Energy recovery

Technical Solutions

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.

Technology Groups

More information on these groups can be found on the dedicated Technology Groups page.

EEDI Formula

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)
  • Tankers
  • 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:

The top line of the EEDI formula can be divided into four key parts:

  1. CO2 emissions due to propulsion power, PME + PPTI
  2. CO2 emissions due to auxiliary power, PAE
  3. CO2 emissions reduction through energy efficient technologies reducing the auxiliary power by generating electricity for normal maximum sea load, PAEeff. Examples include waste heat recovery and photovoltaic power generation.
  4. CO2 emission reduction through energy efficient technologies reducing the propulsion power, Peff. Examples include
    air lubrication systems and wind propulsion systems.

The bottom line of EEDI formula consists of capacity and reference speed Vref, which represent the transport work capacity of the vessel.

For more detailed information related to these parameters, please refer to Resolution MEPC.245(66) 2014 Guidelines on the Method of Calculation of the Attained Energy Efficiency Design Index (EEDI) for New Ships.

For new ships the EEDI is an important driver aimed at promoting the use of more energy efficient equipment. By improving the energy efficiency of the vessel, fuel consumption and the EEDI can be reduced. A wide range of different measures and technologies are available in this portal.

Other References

Low carbon shipping and air pollution control – Information page of IMO for air pollution and energy efficiency

EEDI – Information page of IMO on EEDI

Key findings from the Third IMO GHG Study 2014

Technology Groups

Definitions of maturity levels according to uptake across the maritime industry, and degree of proven technology/principle

Mature

Proven, new or existing technology/principle, with high uptake across the industry.

Semi-mature

Proven, new or existing technology/principle, but with limited uptake across the industry.

Not mature

New unproven-, unproven existing- , or proven existing technology/principle but with very few installations and little to no operational experience.

MACHINERY TECHNOLOGIES

NAME
FUNCTION
TECHNICAL MATURITY
APPLICABILITY
Auxiliary systems optimization
Function

Optimizing auxiliary systems to actual operational profiles, not design conditions

Technical Maturity
Semi-mature
Applicability

All vessels

Engine de-rating
Function

De-rating an engine for reduction of the vessel's maximum speed to increase its efficiency by limiting the potential power output

Technical Maturity
Semi-mature
Applicability

Vessels sailing 10-15% slower than design speed

Engine performance optimization (automatic)
Function

Automatic increase of engine efficiency through testing and tuning according to actual operational load and conditions

Technical Maturity
Semi-mature
Applicability

Mainly for two stroke engines

Engine performance optimization (manual)
Function

Manual increase of engine efficiency through testing and tuning according to actual operational load and conditions

Technical Maturity
Mature
Applicability

All vessels

Exhaust gas boilers on auxiliary engines
Function

Exhaust gas boilers recover the heat from the exhaust gas of auxiliary engines to generate steam, hot water or heat for process heating

Technical Maturity
Semi-mature
Applicability

Vessels without shaft generator

Hybridization (plug-in or conventional)
Function

Use of electricity to replace various modes of power consumption

Technical Maturity
Semi-mature
Applicability

Vessels with large fluctuations in power output (ferries, offshore vessels, tugs)

Improved auxiliary engine load
Function

Increase of the auxiliary engines' load and efficiency by reducing the number of auxiliary engines running

Technical Maturity
Semi-mature
Applicability

All vessels

Shaft generator
Function

Produce electricity from the main propulsion engine

Technical Maturity
Mature
Applicability

All vessels with high power needs and long transits

Shore power
Function

Use of cold ironing in ports to reduce fuel consumption on power producing engines

Technical Maturity
Semi-mature
Applicability

For smaller vessels and in ports with developed solutions for larger vessels

Steam plant operation improvement
Function

Improve operations and maintenance of steam plant system saving fuel on oil fired boiler

Technical Maturity
Mature
Applicability

Mainly crude and product tankers

Waste heat recovery systems
Function

Recover thermal energy from the exhaust gas and convert it into electrical energy

Technical Maturity
Semi-mature
Applicability

All vessels with engines above 10 MW

PROPULSION AND HULL IMPROVEMENTS

NAME
FUNCTION
TECHNICAL MATURITY
APPLICABILITY
Air cavity lubrication
Function

Use of air injection on the wetted hull surfaces to improve a ship’s hydrodynamic performance

Technical Maturity
Semi-mature
Applicability

Most vessels in deep sea trade

Hull cleaning
Function

Removal of fouling on the hull to increase the vessel's hydrodynamic performance

Technical Maturity
Mature
Applicability

All vessels

Hull coating
Function

Reduction of the hull's resistance through water

Technical Maturity
Mature
Applicability

All vessels

Hull form optimization
Function

Optimizing the hull for lower resistance through water

Technical Maturity
Mature
Applicability

All vessels

Hull retrofitting
Function

Retrofitting of the bulbous bow, optimizing thruster tunnels or bilge keel to reduce resistance

Technical Maturity
Mature
Applicability

All vessels

Propeller polishing
Function

Removal of fouling on the propeller

Technical Maturity
Mature
Applicability

All vessels

Propeller retrofitting
Function

Retrofitting the propeller to increase efficiency

Technical Maturity
Semi-mature
Applicability

All vessels

Propulsion Improving Devices (PIDs)
Function

Installation of propulsion improving devices

Technical Maturity
Mature
Applicability

All vessels

ENERGY CONSUMERS

NAME
FUNCTION
TECHNICAL MATURITY
APPLICABILITY
Cargo handling systems (Cargo discharge operation)
Function

Reduction of energy consumption while discharging crude oil by use of model-based studies of the discharge operation

Technical Maturity
Semi-mature
Applicability

Tankers

Energy efficient lighting system
Function

Use of energy efficient lighting equipment, such as LED light, to increase efficiency and remove heat loss from light devices

Technical Maturity
Mature
Applicability

All vessels

Frequency controlled electric motors
Function

Regulating the frequency of the motors in order to adapt the motor optimized load

Technical Maturity
Mature
Applicability

All vessels

ENERGY RECOVERY

NAME
FUNCTION
TECHNICAL MATURITY
APPLICABILITY
Fixed sails or wings
Function

Use sails or wings to replace some of the propulsion power needed

Technical Maturity
Not mature
Applicability

Vessels with enough place on deck (general cargo, tankers, bulkers)

Flettner rotors
Function

Use Flettner rotors to generate power from wind energy

Technical Maturity
Not mature
Applicability

Dependent on trading area and sufficient free deck-surface

Kite
Function

Use a kite to replace some of the propulsion power needed

Technical Maturity
Not mature
Applicability

All vessels

Solar panels
Function

Install solar panels for conversion of solar energy to electricity

Technical Maturity
Not mature
Applicability

Dependent on trading area and sufficient free deck-surface

TECHNICAL SOLUTIONS FOR OPTIMIZING OPERATION

NAME
FUNCTION
TECHNICAL MATURITY
APPLICABILITY
Autopilot adjustment and use
Function

Use of an automatic system to control the vessel's rudder in a more energy efficient manner

Technical Maturity
Mature
Applicability

All vessels

Combinator optimizing
Function

Use of optimized pitch settings and propeller speed for optimized efficiency of propulsion system

Technical Maturity
Mature
Applicability

For vessels with controllable pitch propeller

Efficient DP Operation
Function

Optimize the operation in DP mode

Technical Maturity
Semi-mature
Applicability

Vessels with DP mode

Speed management
Function

Management of the vessel's speed in the most efficient manner

Technical Maturity
Semi-mature
Applicability

All vessels

Trim and draft optimization
Function

Optimizing the trim and draft to reduce the vessel's water resistance

Technical Maturity
Semi-mature
Applicability

All vessels

Weather routing
Function

Including weather conditions when planning a voyage

Technical Maturity
Mature
Applicability

All vessels

*This Information Portal is still under development and further images will be added. For suggestions and additional technologies to be included in the Information Portal, please use the GreenVoyage2050 Contact Form.

This Energy Efficiency Technologies Information Portal was developed in cooperation with DNV GL.

This webpage serves as an Information Portal for Energy Efficiency Technologies for Ships. IMO does not make any warranties or representations as to the accuracy or completeness of the information provided. View our disclaimer