The International Maritime Organization (IMO) introduced the mandatory Energy Efficiency Design Index (EEDI) for all new ship constructed after 1^st January 2013. The objective was to promote energy efficient ship designs and thereby contribute to the society with lower emissions and more cost effective sea transportation. Important part of the EEDI verification process is model tank testing. Therefore, the demand for the standard model propulsion test was raised to comply with the EEDI verification objectives and requirements. In this respect some new elements of the propulsion testing were required, such as the mandatory EEDI and sea trial loading conditions, the need for carrying out the so called “load varying” test, the need to elaborate on the correlation allowance coefficients  for different loading conditions, etc. 

The objectives of the proposed paper are to present (shortly) the EEDI verification process; the associated new requirements for the model testing scope; the specifics of the load varying propulsion test and the influence of propeller loading on the propulsive efficiency. The presentation will be further illustrated with practical examples of the load varying test for three typical types of vessels, with demonstration of the propulsive efficiency variation level depending on the propeller load variation. Conclusions and recommendation will focus on the need and importance of the load varying test consideration.

The intended structure of the full paper is presented below:

• Presentation of EEDI and its verification process
• Preliminary verification – model testing input
• Speed/power sea trial – short presentation (block diagram)
• Corrections to be applied
• Direct power method presentation and originating new requirements
• Load varying SP test – presentation
• Explanation of ETAD correction
• Practical Examples – Tanker, Bulk carrier, Containership; magnitude of ETAD correction and influence on the speed/power curve
• Conversion from trial to EEDI condition
• Conclusions and recommendations