The purpose of these guidelines is to assist recognized
organizations in the validation of Electric Power Tables (EPT) for
the calculation of the Energy Efficiency Design Index (EEDI) for ships.
As such, these guidelines support the implementation of the EEDI Calculation
guidelines and the Guidelines on survey and certification of
the Energy Efficiency Design Index (EEDI). These guidelines
will also assist shipowners, shipbuilders, ship designers and manufacturers
in relation to aspects of the development of more energy efficient
ships and also in understanding the procedures for the EPT-EEDI validation.
These guidelines provide a framework for the uniform application of the
EPT-EEDI validation process for ships for which required auxiliary engine power is
calculated under paragraph 2.2.5.7 of the EEDI Calculation Guidelines.
3.1
Applicant means an organization,
primarily a shipbuilder or a ship designer, which requests the EPT-EEDI
validation in accordance with these guidelines.
3.2
Validator means a recognized
organization which conducts the EPT-EEDI validation in accordance
with these guidelines.
3.3
Validation for the purpose of
these guidelines means review of submitted documents and survey during
construction and sea trials.
3.4
Standard EPT-EEDI-Form refers
to the layout given in appendix 3, containing the EPT-EEDI results
that will be the subject of validation. Other supporting documents
submitted for this purpose will be used as reference only and will
not be subject to validation.
3.5
PAE
herein is defined as per the definition in paragraph 2.2.5.6 of the EEDI
Calculation Guidelines.
3.6
Ship service and engine-room
loads refer to all the load groups which are needed for the hull,
deck, navigation and safety services, propulsion and auxiliary engine
services, engine-room ventilation and auxiliaries and ship's general
services.
3.7
Diversity factor is the ratio
of the "total installed load power" and the "actual load power" for
continuous loads and intermittent loads. This factor is equivalent
to the product of service factors for load, duty and time.
4.1 These guidelines are applicable to ships as stipulated
in paragraph 2.2.5.7 of the EEDI Calculation Guidelines.
4.2 These guidelines should be applied for new
ships for which an application for an EPT-EEDI validation has been
submitted to a validator.
4.3 The steps of the validation process include:
.1 review of documents during the design stage
-
.1 check if all relevant loads are listed in the
EPT;
-
.2 check if reasonable service factors are used;
and
-
.3 check the correctness of the PAE calculation
based on the data given in the EPT.
.2 survey of installed systems and components
during construction stage
5.1 The applicant should provide as a minimum
the ship electric balance load analysis.
5.2 Such information may contain shipbuilders'
confidential information. Therefore, after the validation, the validator
should return all or part of such information to the applicant at
the applicant's request.
5.3 A special EEDI condition during sea trials
may be needed and defined for each ship and included in the sea trial
schedule. For this condition, a special column should be inserted
into the EPT.
6
PROCEDURES FOR VALIDATION
PAE should be calculated in accordance with the
EPT-EEDI Calculation guidelines. EPT-EEDI validation should be conducted
in two stages: preliminary validation at the design stage and final
validation during sea trials. The validation process is presented
in figure 1.
Figure 1: Basic flow of EPT-EEDI validation process
6.2
Preliminary validation
at the design stage
6.2.1 For the preliminary validation at the design
stage, the applicant should submit to a validator an application for
the validation of EPT-EEDI, inclusive of the EPT-EEDI Form, and all
the relevant and necessary information for the validation as supporting
documents.
6.2.2 The applicant should supply as a minimum
the supporting data and information, as specified in appendix A (to
be developed).
6.2.3 The validator may request from the applicant
additional information to that contained in these guidelines, as necessary,
to enable the validator to examine the calculation process of the
EPT-EEDI. The estimation of the ship EPT-EEDI at the design stage
depends on each applicant's experience, and it may not be practicable
to fully examine the technical aspects and details of each machinery
component. Therefore, the preliminary validation should focus on the
calculation process of the EPT-EEDI that should follow best marine
practices.
6.3.1 The final validation process should as a
minimum should include a check of the ship electric load analysis
to ensure that all electric consumers are listed; their specific data
and the calculations in the power table itself are correct and are
supported by sea trial results. If necessary, additional information
has to be requested.
6.3.2 For the final validation, the applicant
should revise the EPT-EEDI Form and supporting documents as necessary,
by taking into account the characteristics of the machinery and other
electrical loads actually installed on board the ship. The EEDI condition
at sea trials should be defined and the expected power requirements
in these conditions documented in the EPT. Any changes within the
EPT from design stage to construction stage should be highlighted
by the shipyard.
6.3.3 The preparation for the final validation
includes a desk top check comprising:
-
.1 consistency of preliminary and final EPT;
-
.2 changes of service factors (compared to the
preliminary validation);
-
.3 all electric consumers are listed;
-
.4 their specific data and the calculations in
the power table itself are correct; and
-
.5 in case of doubt, component specification data
is checked in addition.
6.3.4 A survey prior to sea trials is performed
to ensure that machinery characteristics and data as well as other
electric loads comply with those recorded in the supporting documents.
This survey does not cover the complete installation but selects randomly
a number of samples.
6.3.5 For the purpose of sea trial validation,
the surveyor will check the data of selected systems and/or components
given in the special column added to the EPT for this purpose or the
predicted overall value of electric load by means of practicable measurements
with the installed measurement devices.
7
ISSUANCE OF THE EPT-EEDI
STATEMENT OF VALIDATION
7.1 The validator should stamp the EPT-EEDI Form
as "Noted" having validated the EPT-EEDI in the preliminary validation
stage, in accordance with these guidelines.
7.2 The validator should stamp the EPT-EEDI Form
as "Endorsed" having validated the final EPT-EEDI in the final validation
stage in accordance with these guidelines.