Ingangsdatum: 01-01-2013
Geldig tot en met: 16-05-2013
4.3 - Final verification of the attained EEDI at sea
trial
4.3.1 Sea trial conditions should be set as
conditions specified in paragraph 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
NOx Technical File as necessary. The test
procedure should include, at 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:
- propulsion and power supply system, particulars of the
engines, and other relevant items described in the EEDI
Technical File;
- draught and trim;
- sea conditions;
- ship speed; and
- shaft power and RPM of the main engine.
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 ISO 15016:2002 or the equivalent.
4.3.6 Ship speed should be measured in
accordance with ISO 15016:2002 or the equivalent and at more
than two points of which range includes the power of the main
engine as specified in paragraph 2.5 of the EEDI Calculation
Guidelines.
4.3.7 The main engine output 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 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, tide,
waves, shallow water and displacement in accordance with ISO
15016:20021 or the
equivalent which may be acceptable provided that the concept of
the method is transparent for the verifier and publicly
available/accessible. 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:
- for ships for which sea trial is conducted under the
condition as specified in paragraph 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 2.5
of the EEDI Calculation Guidelines; and
- for ships for which sea trial cannot be conducted under
the condition as specified in paragraph 2.2 of the EEDI
Calculation Guidelines: if the measured ship speed at the
power of the main engine as specified in paragraph 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 of the EEDI
Calculation Guidelines by an appropriate correction method
that is agreed by the verifier.
An example of possible methods of the speed adjustment is given
in figure 2:
Note: Further consideration would be
necessary for speed adjustment methodology in paragraph
4.3.9.2 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.
Figure 2: An Example of Possible Ship
Speed
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 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.
4.3.12 The EEDI Technical File
should be revised, as necessary, by taking into account the
results of sea trial. Such revision should include, as
applicable, the adjusted power curve based on the results of sea
trial (namely, modified ship speed under the condition as
specified in paragraph 2.2 of the EEDI Calculation Guidelines),
the finally determined deadweight/gross tonnage and SFC
described in the approved NOx Technical File, and the
recalculated attained EEDI based on these modifications.
4.3.13 The EEDI Technical File, if
revised, should be submitted to the verifier for the
confirmation that the (revised) attained EEDI is calculated in
accordance with regulation 20 of MARPOL Annex VI and the EEDI
Calculation Guidelines.
1
ITTC Recommended Procedure
7.5-04-01-01.2 is considered as preferable standard.