MEPC.1/Circ.682 - Interim guidelines for voluntary verification of the energy efficiency design index

Interim guidelines for voluntary verification of the energy efficiency design index

682 Interim guidelines for voluntary verification of the energy efficiency design index

Interim guidelines for voluntary verification of the energy efficiency design index  

		dd-mm-yyyy = Entry into force
Document	MEPC.1/Circ.682	17-08-2009
Revoked by	MEPC/Res.214(63)	31-12-2012

682 Interim guidelines for voluntary verification of the energy efficiency design index

 Interim guidelines for voluntary verification of the energy efficiency design index

1. The Marine Environment Protection Committee, at its fifty-ninth session (13 to 17 July 2009), recognizing the need to develop a method for voluntary verification of the energy efficiency design index for new ships in order to promote uniform use of the Interim Guidelines on the method of calculation of the energy efficiency design index for new ships (MEPC.1/Circ.681), agreed to circulate the Interim Guidelines on voluntary verification of the energy efficiency design index, as set out in the annex.
   
   

2. Member Governments are invited to use the annexed Interim Guidelines for the purpose of tests and trials on a voluntary basis.
   
   

3. Member Governments and observer organizations are also invited to provide the outcome and experiences in applying the Interim Guidelines to future sessions of the Committee for further improvement of the Interim Guidelines.

Annex Interim guidelines for voluntary verification of the energy design index

Interim guidelines for voluntary verification of the energy design index

 

 

1 General

1. General

The purpose of these Guidelines is to assist verifiers of Energy Efficiency Design Index (EEDI) of ships in conducting the verification, on a voluntary basis, of the EEDI which should be calculated in accordance with the Interim Guidelines on the Method of Calculation of the EEDI for New Ships (“EEDI Guidelines”, hereafter), and assist shipowners, shipbuilders and manufacturers being related to the energy efficiency of a ship and other interested parties in understanding the procedures of the voluntary EEDI verification.

2 Definitions

2 - Definitions¹

2.1 Verifier means an organization which conducts the voluntary EEDI verification in accordance with these Guidelines, including Administrations, classification societies and other organizations which possess technical expertise necessary for conducting the EEDI verification.

2.2 Ship of the same type means a ship of which hull form (expressed in the lines such as sheer plan and body plan) excluding additional hull features such as fins and of which principal particulars are identical to that of the base ship.

2.3 Ship of a similar type means a ship of which hull form (expressed in the lines such as sheer plan and body plan) excluding additional hull features such as fins and of which principal particulars are largely identical to that of the base ship.

2.4 Tank test means model towing tests, model self-propulsion tests and model propeller open water tests. Numerical tests may be accepted as equivalent to model tests if they are performed under documented conditions agreed by the shipbuilder and shipowner.

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¹ Other terms used in these guidelines have the same meaning as those defined in the EEDI Guidelines.

3 Applications

3. Applications

These Guidelines should be applied on a voluntary basis to new ships for which an application for an EEDI verification has been submitted to a verifier.

4 Procedures for verification

4. Procedures for verification

4.1 General

4.1 General

Attained EEDI should be calculated in accordance with the EEDI Guidelines. Voluntary EEDI verification should be conducted on two stages: preliminary verification at the design stage, and final verification at the sea trial. The basic flow of the verification process is presented in Figure 1.

^* To be conducted by a test organization or a shipbuilder itself.

Figure 1 – Basic Flow of Verification Process

4.2 Preliminary verification

4.2 Preliminary verification at the design stage

4.2.1 For the preliminary verification at the design stage, a shipowner should submit to a verifier an application for the verification and an EEDI Technical File containing the necessary information for the verification and other relevant background documents.

4.2.2 EEDI Technical File, which is to be developed by either a shipowner or a shipbuilder, should include at least but not limited to:

1. deadweight (DWT) or gross tonnage (GT) for passenger and ro-ro passenger ships, the shaft power of the main and auxiliary engines, the ship speed on deep water in the maximum design loaded conditions at the 75% of the maximum continuous rate (MCR) for the main engine, the specific fuel consumption (SFC) of the main engine at the 75% of MCR power, the SFC of the auxiliary engines at the 50% MCR power, and the electric power table for certain ship types, as necessary, as defined in the EEDI Guidelines;
   
   

2. power curves (kW – knot) estimated at design stage under fully loaded condition and sea trial condition;
   
   

3. principal particulars and the overview of propulsion system and electricity supply system on board;
   
   

4. estimation process and methodology of the power curves at design stage;
   
   

5. description of energy saving equipment; and
   
   

6. calculated value of the Attained EEDI.
   
   

4.2.3 Sea trial conditions should be set in fully loaded condition, if possible – e.g., in case of tankers.

4.2.4 The SFC of the main and auxiliary engines should be quoted from the approved NO_xTechnical File. For the confirmation of the SFC, a copy of the approved NO_xTechnical File should be submitted to the verifier. In case NO_xTechnical File has not been approved at the time of the application for preliminary verification, 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 NOx Technical File should be submitted to the verifier.

Note: SFC in the NO_xTechnical 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 problems for further consideration:

- The definition of “member engines” given in NO_xTechnical File is broad and specification of engines belonging to the same family group may vary; and

- The rate of NO_xemission of the parent engine is the highest in the group/family – i.e. CO₂emission, which is in the trade-off relationship with NO_xemission, can be lower than the other engines in the group/family.

Thus, for member engines of which specifications are different from the parent engine, how to determine SFC should be considered further. For instance, measured values of SFC at test bed of manufacturers could be used.

4.2.5 The power curves used for the preliminary verification at the design stage should be based on reliable results of tank test. 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/similar type.

4.2.6 The verifier may request the shipbuilder for additional information on top of those contained in Technical File, as necessary, to examine the calculation process of the Attained EEDI. The estimation of the ship speed at the design stage much depends on each shipbuilder’s experiences, 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 coefficient. Therefore, the preliminary verification should focus on the calculation process of the Attained EEDI that should follow the EEDI Guidelines.

Note: A possible way forward for more robust verification is to establish a standard methodology of deriving the ship speed from the outcomes of tank test, by setting standard values for experience-based correction factors such as roughness coefficient and wake coefficient. In this way, ship-by-ship performance comparison 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.

Note: For ensuring the quality of tank tests, it would be desirable in the future that an organization conducting a tank test be authorized by the Administration or an organization recognized by it in accordance with the guidelines developed by the Organization.

4.2.7 Additional information that the verifier should request the shipbuilder to provide directly to it (i.e. not to be contained in Technical File) includes but not limited to:

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;
   
   

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;
   
   

3. lightweight of the ship and displacement table for the verification of the deadweight;
   
   

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 at fully loaded condition;
   
   

5. detailed calculation process of the ship speed, which should include the estimation basis of experience-based parameters such as roughness coefficient, wake coefficient; and
   
   

6. reasons for exempting a tank test, if applicable; this should include lines and tank test results of the ships of same/similar type, and the comparison of the principal particulars of such ships and the ship in question. Appropriate technical justification should be provided for regarding the tank test unnecessary.
   

 

4.2.8 Such additional information may contain shipbuilders’ confidential information.
Therefore, after the verification, the verifier should return all or part of such information to the shipbuilder at its request.

4.3 Final verification

 

4.3 Final verification of the Attained EEDI at sea trial

4.3.1 Prior to the sea trial, a shipowner should submit the application for the verification of EEDI together with the final displacement table and the measured lightweight, or a copy of the survey report of deadweight, as well as a copy of NO^_xTechnical File as necessary.

4.3.2 The verifier should attend the sea trial and confirm:

1. propulsion and power supply system, particulars of the engines, and other relevant items described in the EEDI Technical File;
   
   

2. draft and trim;
   
   

3. sea conditions;
   
   

4. ship speed; and
   
   

5. shaft power of the main engine.
   
   

4.3.3 Draft and trim should be confirmed by the draft measurements taken prior to the sea trial. The draft and trim should be as close as practical to those at the assumed conditions used for estimating the power curves.

4.3.4 Sea conditions should be measured in accordance with ISO15016:2002 or the equivalent.

4.3.5 Ship speed should be measured in accordance with ISO15016:2002 or the equivalent and at more than two points of which range includes the 75% of MCR power.

4.3.6 The shaft power of the main engine should be measured by shaft power meter or estimated by fuel rack. Otherwise, it should be measured by a method which the engine manufacturer recommends and the verifier approves.

4.3.7 The shipbuilder should develop power curves based on the measured ship speed and the measured shaft power of the main engine at sea trial. For the development of the power curves, the shipbuilder should calibrate the measured ship speed, if necessary, by taking into account the effects of wind, tide and waves in accordance with ISO15016:2002 or the equivalent.

4.3.8 The shipbuilder 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:

1. for ships for which sea trial is conducted in fully loaded condition (e.g., tankers): the Attained EEDI should be recalculated using the measured ship speed at sea trial at 75% of MCR power; and
   
   

2. for ships for which sea trial cannot be conducted in fully loaded condition (e.g., dry bulkers): if the measured ship speed at 75% of MCR power of the main engine 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 in fully loaded condition 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 4.3.8.2. One of concerns relates to a possible situation where the power curve for sea trial condition is estimated in 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 Adjustment

4.3.9 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 NO_xTechnical File, the shipowner or the shipbuilder should recalculate the Attained EEDI by using SFC in the approved NO_xTechnical File.

4.3.10 The shipowner or the shipbuilder should revise an EEDI Technical File, 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 at 75% of MCR power of the main engine at full-loaded condition) and SFC described in the approved NO_xTechnical File, and the recalculated Attained EEDI based on these modifications.

4.3.11 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 the EEDI Guidelines.

5 Issuance of the EEDI

Issuance of the EEDI verification report

5.1 The verifier should issue the Report on the Preliminary Verification of EEDI after it verified the Attained EEDI at design stage in accordance with Sections 4.1 and 4.2 of these Guidelines.

5.2 The verifier should issue the report on the Verification of EEDI after it verified the Attained EEDI after the sea trial in accordance with Sections 4.1 and 4.3 of these Guidelines.

• Informatietype: Internationaal
• Documentsoort: Circulaire niet in wetten.nl
• Toegangsrechten: Intern
• Identificatie: PUC_1683_14
• Versie: 1
• Datum beschikbaarheid: 17-11-2009
• Geldigheid van: 17-08-2009
• tot en met: 31-12-2012
• Wijzigingsdatum: 09-06-2021
• Titel: MEPC.1/Circ.682 - Interim guidelines for voluntary verification of the energy efficiency design index
• Organisatie: International Maritime Organization (IMO)
• Taal: Nederlands
• Thema: MEPC/Circ. 600 until 699