1 General
The purpose of these guidelines is to assist verifiers of the Energy
Efficiency Design Index (EEDI) of ships in conducting the survey and certification
of the EEDI, in accordance with regulations 5, 6, 7, 8 and 9 of MARPOL Annex VI, and
assist shipowners, shipbuilders, manufacturers and other interested parties in
understanding the procedures for the survey and certification of the EEDI.
2.1 Verifier means an Administration, or organization duly
authorized by it, which conducts the survey and certification of the EEDI in
accordance with regulations 5, 6, 7, 8 and 9 of MARPOL Annex VI and these
Guidelines.
2.2 Ship of the same type means a ship the hull form (expressed in
the lines such as sheer plan and body plan), excluding additional hull features such
as fins, and principal particulars of which are identical to that of the base ship.
2.3 Tank test means model towing tests, model self-propulsion
tests and model propeller open water tests. Numerical calculations may be accepted
as equivalent to model propeller open water tests or used to complement the tank
tests conducted (e.g. to evaluate the effect of additional hull features such as
fins, etc. on ships' performance) with the approval of the verifier.
3 Application
These guidelines should be applied to new ships for which an application for an
initial survey or an additional survey specified in regulation 5 of MARPOL Annex VI
has been submitted to a verifier.
4 Procedures for survey and certification
4.1.1 The attained EEDI should be calculated in accordance with regulation 20 of MARPOL Annex VI and the
2018 Guidelines on the method of calculation of the attained Energy
Efficiency Design Index (EEDI) for new ships (resolution MEPC.308(73)) (EEDI Calculation Guidelines).
Survey and certification of the EEDI should be conducted in two stages: preliminary
verification at the design stage and final verification at the sea trial. The basic
flow of the survey and certification process is presented in figure 1.
4.1.2 The information used in the verification process may contain
confidential information of submitters which requires Intellectual Property Rights
(IPR) protection. In the case where the submitter wants a non-disclosure agreement
with the verifier, the additional information should be provided to the verifier
upon mutually agreed terms and conditions.
Figure 1: Basic flow of survey and certification process
4.2 Preliminary verification of the attained EEDI at the design stage
4.2.1 For the preliminary verification at the design stage, an
application for an initial survey and an EEDI Technical File containing the
necessary information for the verification and other relevant background documents
should be submitted to a verifier.
4.2.2 The EEDI Technical File should be written at least in English. The
EEDI Technical File should include as a minimum, but not limited to:
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.1 deadweight (DWT) or gross tonnage (GT) for passenger and
ro-ro passenger ships, the maximum continuous rating (MCR) of the main
and auxiliary engines, the ship speed (Vref), as
specified in paragraph 2.2.2 of the EEDI Calculation Guidelines, type of
fuel, the specific fuel consumption (SFC) of the main engine at
75% of MCR power, the SFC of the auxiliary engines at 50% MCR
power, and the electric power tablefootnote for certain ship types, as
necessary, as defined in the EEDI Calculation Guidelines;
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.2 power curve(s) (kW – knot) estimated at design stage under
the condition as specified in paragraph 2.2.2 of the EEDI Calculation
Guidelines, and, in the event that the sea trial is carried out in a
condition other than the above condition, also a power curve estimated
under the sea trial condition;
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.3 principal particulars, ship type and the relevant information to
classify the ship as such a ship type, classification notations and an
overview of the propulsion system and electricity supply system on
board;
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.4 estimation process and methodology of the power curves at design
stage;
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.5 description of energy saving equipment;
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.6 calculated value of the attained EEDI, including the calculation
summary, which should contain, at a minimum, each value of the
calculation parameters and the calculation process used to determine the
attained EEDI;
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.7 calculated values of the attained EEDIweather and
fw value (not equal to 1.0), if those
values are calculated, based on the EEDI Calculation Guidelines; and
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.8 for LNG carriers:
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.1 type and outline of propulsion systems (such as direct drive
diesel, diesel electric, steam turbine);
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.2 LNG cargo tank capacity in m3 and BOR
as defined in paragraph 2.2.5.6.3 of the EEDI Calculation
Guidelines;
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.3 shaft power of the propeller shaft after transmission gear at
100% of the rated output of motor (MPPMotor)
and η(i) for diesel electric;
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.4 maximum continuous rated power
(MCRSteamTurbine) for steam turbine;
and
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.5 SFCSteamTurbine for steam
turbine, as specified in paragraph 2.2.7.2 of the EEDI
Calculation Guidelines.
A sample of an EEDI Technical File is provided in appendix 1.
4.2.3 For ships equipped with dual-fuel engine(s) using LNG and fuel oil,
the C F-factor for gas (LNG) and the specific fuel consumption
( SFC) of gas fuel should be used by applying the following criteria as a
basis for the guidance of the Administration:
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.1 final decision on the primary fuel rests with the
Administration;
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.2 the ratio of calorific value of gas fuel (LNG) to total
marine fuels (HFO/MGO), including gas fuel (LNG) at design conditions
should be equal to or larger than 50% in accordance with the formula
below. However, the Administration can accept a lower value of the
percentage taking into account the intended voyages:

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whereby:
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Vgas is the total net tank volume of gas
fuel on board in m3;
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Vliquid is the total net tank volume of
every liquid fuel on board in m3;
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ρgas is the density of gas fuel in
kg/m3;
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ρliquid is the density of every
liquid fuel in kg/m3;
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LCVgas is the low calorific value
of gas fuel in kJ/kg;
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LCVliquid is the low calorific
value of liquid fuel in kJ/kg;
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Kgas is the filling rate for gas
fuel tanks;
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Kliquid is the filling rate for
liquid fuel tanks.
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Normal density, Low Calorific Value and filling rate
for tanks of different kinds of fuel are listed below.
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Type of
fuel
|
Density (kg/m3)
|
Low
Calorific Value (kJ/kg)
|
Filling
rate for tanks
|
Diesel/Gas
Oil
|
900
|
42700
|
0.98
|
Heavy Fuel
Oil
|
991
|
40200
|
0.98
|
Liquefied
Natural Gas (LNG)
|
450
|
48000
|
0.95*
|
* Subject to verification of tank filling limit.
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.3 in case the ship is not fully equipped with dual-fuel
engines, the CF-factor for gas (LNG) should apply only for those
installed engines that are of dual-fuel type and sufficient gas fuel
supply should be available for such engines; and
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.4 LNG fuelling solutions with exchangeable (specialized) LNG
tank-containers should also fall under the terms of LNG as primary
fuel.
4.2.4 The SFC of the main and auxiliary engines should be quoted
from the approved NO x Technical File and should be corrected to the value
corresponding to the ISO standard reference conditions using the standard lower
calorific value of the fuel oil (42,700 kJ/kg), referring to ISO 15550:2002 and ISO
3046-1:2002. For the confirmation of the SFC, a copy of the approved
NO x Technical File and documented summary of the correction
calculations should be submitted to the verifier. In cases where the NO x
Technical File has not been approved at the time of the application for initial
survey, the test reports provided by manufacturers should be used. In this case, at
the time of the sea trial verification, a copy of the approved NO x
Technical File and documented summary of the correction calculations should be
submitted to the verifier. In the case that gas fuel is determined as primary fuel
in accordance with paragraph 4.2.3 and that installed engine(s) have no approved
NO x Technical File tested in gas mode, the SFC of gas mode
should be submitted by the manufacturer and confirmed by the verifier.
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Note:
SFC in the NOx Technical File are the values of a
parent engine, and the use of such value of SFC for the EEDI
calculation for member engines may have the following technical issues
for further consideration:
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.1 the definition of "member engines" given in the
NOx Technical File is broad and specification of engines
belonging to the same group/family may vary; and
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.2 the rate of NOx emission of the parent engine
is the highest in the group/family – i.e. CO2 emission, which
is in the trade-off relationship with NOx emission, can be
lower than the other engines in the group/family.
4.2.5 For ships to which regulation 21 of MARPOL Annex VI applies, the
power curves used for the preliminary verification at the design stage should be
based on reliable results of tank tests. A tank test for an individual ship may be
omitted based on technical justifications such as availability of the results of
tank tests for ships of the same type. In addition, the omission of tank tests is
acceptable for a ship for which sea trials will be carried out under the condition
as specified in paragraph 2.2.2 of the EEDI Calculation Guidelines, upon agreement
of the shipowner and shipbuilder and with the approval of the verifier. To ensure
the quality of tank tests, the ITTC quality system should be taken into account.
Model tank tests should be witnessed by the verifier.
4.2.6 The verifier may request further information from the submitter,
in addition to that contained in the EEDI Technical File, as necessary, to examine
the calculation process of the attained EEDI. For the estimation of the ship speed
at the design stage much depends on each shipbuilder's experience, and it may not be
practicable for any person/organization other than the shipbuilder to fully examine
the technical aspects of experience-based parameters, such as the roughness
coefficient and wake scaling coefficient. Therefore, the preliminary verification
should focus on the calculation process of the attained EEDI to ensure that it is
technically sound and reasonable and follows regulation 20 of MARPOL Annex VI and the EEDI
Calculation Guidelines.
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Note 1: A possible way forward for more robust
verification is to establish a standard methodology of deriving the ship
speed from the outcome of tank tests, by setting standard values for
experience-based correction factors such as roughness coefficient and
wake scaling coefficient. In this way, ship-by-ship performance
comparisons could be made more objectively by excluding the possibility
of arbitrary setting of experience-based parameters. If such
standardization is sought, this would have an implication on how the
ship speed adjustment based on sea trial results should be conducted, in
accordance with paragraph 4.3.8 of these Guidelines.
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Note 2: A joint industry standard to support the method and role
of the verifier is expected to be developed.
4.2.7 Additional information that the verifier may request the submitter
to provide includes, but is not limited to:
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.1 descriptions of a tank test facility; this should include the name of
the facility, the particulars of tanks and towing equipment, and the
records of calibration of each monitoring equipment;
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.2 lines of a model ship and an actual ship for the verification of the
appropriateness of the tank test; the lines (sheer plan, body plan and
half-breadth plan) should be detailed enough to demonstrate the
similarity between the model ship and the actual ship;
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.3 lightweight of the ship and displacement table for the verification of
the deadweight;
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.4 detailed report on the method and results of the tank
test; this should include at least the tank test results at sea trial
condition and under the condition as specified in paragraph 2.2.2 of the
EEDI Calculation Guidelines;
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.5 detailed calculation process of the ship speed, which should include
the basis for the estimation of experience-based parameters such as
roughness coefficient and wake scaling coefficient;
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.6 reasons for exempting a tank test, if applicable; this should include
lines and tank test results of ships of the same type, and the
comparison of the principal particulars of such ships and the ship in
question. Appropriate technical justification should be provided,
explaining why the tank test is unnecessary; and
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.7 for LNG carriers, detailed calculation process of
PAE and SFCSteamTurbine.
4.2.8 The verifier should issue the report on the Preliminary
Verification of the EEDI after it has verified the attained EEDI at the design
stage, in accordance with paragraphs 4.1 and 4.2 of these Guidelines.
4.3 Final verification of the attained EEDI at sea trial
4.3.1 Sea trial conditions should be set as the conditions specified in
paragraph 2.2.2 of the EEDI Calculation Guidelines, if possible.
4.3.2 Prior to the sea trial, the following documents should be
submitted to the verifier: a description of the test procedure to be used for the
speed trial, the final displacement table and the measured lightweight, or a copy of
the survey report of deadweight, as well as a copy of the NOx Technical
File, as necessary. The test procedure should include, as a minimum, descriptions of
all necessary items to be measured and corresponding measurement methods to be used
for developing power curves under the sea trial condition.
4.3.3 The verifier should attend the sea trial and confirm:
4.3.4 Draught and trim should be confirmed by the draught measurements
taken prior to the sea trial. The draught and trim should be as close as practical
to those at the assumed conditions used for estimating the power curves.
4.3.5 Sea conditions should be measured in accordance with ITTC
Recommended Procedure 7.5-04-01-01.1 Speed and Power Trials 2017 or ISO 15016:2015.
4.3.6 Ship speed should be measured in accordance with ITTC Recommended
Procedure 7.5-04-01-01.1 Speed and Power Trials 2017 or ISO 15016:2015, and at more
than two points of which range includes the power of the main engine as specified in
paragraph 2.2.5 of the EEDI Calculation Guidelines.
4.3.7 The main engine output, shaft power of propeller shaft (for LNG
carriers having diesel electric propulsion system) or steam turbine output (for LNG
carrier having steam turbine propulsion system) should be measured by shaft power
meter or a method which the engine manufacturer recommends and the verifier
approves. Other methods may be acceptable upon agreement of the shipowner and
shipbuilder and with the approval of the verifier.
4.3.8 The submitter should develop power curves based on the measured
ship speed and the measured output of the main engine at sea trial. For the
development of the power curves, the submitter should calibrate the measured ship
speed, if necessary, by taking into account the effects of wind, current, waves,
shallow water, displacement, water temperature and water density in accordance with
ITTC Recommended Procedure 7.5-04-01-01.2 Speed and Power Trials 2017 or ISO
15016:2015. Upon agreement with the shipowner, the submitter should submit a report
on the speed trials including details of the power curve development to the verifier
for verification.
4.3.9 The submitter should compare the power curves obtained as a result
of the sea trial and the estimated power curves at the design stage. In case
differences are observed, the attained EEDI should be recalculated, as necessary, in
accordance with the following:
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.1 for ships for which sea trial is conducted under the
condition as specified in paragraph 2.2.2 of the EEDI Calculation
Guidelines: the attained EEDI should be recalculated using the measured
ship speed at sea trial at the power of the main engine as specified in
paragraph 2.2.5 of the EEDI Calculation Guidelines; and
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.2 for ships for which sea trial cannot be conducted under
the condition as specified in paragraph 2.2.2 of the EEDI Calculation
Guidelines: if the measured ship speed at the power of the main engine
as specified in paragraph 2.2.5 of the EEDI Calculation Guidelines at
the sea trial conditions is different from the expected ship speed on
the power curve at the corresponding condition, the shipbuilder should
recalculate the attained EEDI by adjusting ship speed under the
condition as specified in paragraph 2.2.2 of the EEDI Calculation
Guidelines by an appropriate correction method that is agreed by the
verifier.
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.3 An example of the scheme of conversion from trial condition to EEDI
condition at EEDI power is given as follows:
Vref is obtained from the results of the
sea trials at trial condition using the speed-power curves predicted by
the tank tests. The tank tests shall be carried out at both draughts:
trial condition corresponding to that of the S/P trials and EEDI
condition. For trial conditions the power ratio αP between
model test prediction and sea trial result is calculated for constant
ship speed. Ship speed from model test prediction for EEDI condition at
EEDI power multiplied with αP is
Vref.

where:
PTrial,P : power at trial condition
predicted by the tank tests
PTrial,S : power at trial condition
obtained by the S/P trials
αP: power ratio
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.4 Figure 2 shows an example of the scheme of conversion to derive the
resulting ship speed at EEDI condition ( Vref) at EEDI
power.
Figure 2: An example of scheme of conversion from
trial condition to EEDI condition at EEDI power
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Note: Further consideration would be necessary for
speed adjustment methodology in paragraphs 4.3.9.2 to 4.3.9.4 of these
Guidelines. One of the concerns relates to a possible situation where
the power curve for sea trial condition is estimated in an excessively
conservative manner (i.e. power curve is shifted in a leftward
direction) with the intention to get an upward adjustment of the ship
speed by making the measured ship speed at sea trial easily exceed the
lower-estimated speed for sea trial condition at design stage.
4.3.10 In cases where the finally determined deadweight/gross tonnage
differs from the designed deadweight/gross tonnage used in the EEDI calculation
during the preliminary verification, the submitter should recalculate the attained
EEDI using the finally determined deadweight/gross tonnage. The finally determined
gross tonnage should be confirmed in the Tonnage Certificate of the ship.
4.3.11 The electrical efficiency η(i) should be taken
as 91.3% for the purpose of calculating the attained EEDI. Alternatively, if a value
of more than 91.3% is to be applied, η(i) should be obtained by
measurement and verified by a method approved by the verifier.
4.3.12 In case where the attained EEDI is calculated at the preliminary
verification by using SFC based on the manufacturer's test report, due to the
non-availability at that time of the approved NOx Technical File, the
EEDI should be recalculated by using SFC in the approved NOx
Technical File. Also, for steam turbines, the EEDI should be recalculated by using
SFC confirmed by the Administration, or an organization recognized by the
Administration, at the sea trial.
4.3.13 The EEDI Technical File should be revised, as necessary, by
taking into account the results of sea trials. Such revision should include, as
applicable, the adjusted power curve based on the results of sea trials (namely,
modified ship speed under the condition as specified in paragraph 2.2.2 of the EEDI
Calculation Guidelines), the finally determined deadweight/gross tonnage, η
for LNG carriers having diesel electric propulsion system and SFC described
in the approved NOx Technical File, and the recalculated attained EEDI
based on these modifications.
4.3.14 The EEDI Technical File, if revised, should be submitted to the
verifier for confirmation that the (revised) attained EEDI is calculated in
accordance with regulation 20 of MARPOL Annex VI and the EEDI
Calculation Guidelines.
4.4 Verification of the attained EEDI in case of major conversion
4.4.1 In cases of a major conversion of a ship, the shipowner should
submit to a verifier an application for an additional survey with the EEDI Technical
File duly revised, based on the conversion made and other relevant background
documents.
4.4.2 The background documents should include as a minimum, but are not
limited to:
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.1 details of the conversion;
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.2 EEDI parameters changed after the conversion and the technical
justifications for each respective parameter;
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.3 reasons for other changes made in the EEDI Technical File, if any; and
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.4 calculated value of the attained EEDI with the calculation summary,
which should contain, as a minimum, each value of the calculation
parameters and the calculation process used to determine the attained
EEDI after the conversion.
4.4.3 The verifier should review the revised EEDI Technical File and
other documents submitted and verify the calculation process of the attained EEDI to
ensure that it is technically sound and reasonable and follows regulation 20 of MARPOL Annex VI and the EEDI
Calculation Guidelines.
4.4.4 For verification of the attained EEDI after a conversion, speed
trials of the ship are required, as necessary.
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