GREEK SECTION TECHNICAL MEETING REPORT
TOPIC: ‘‘Model-Based Methods for Energy Efficiency Improvements on Board Ships’’
Report by Dr. Christos A. Kontovas
On June 14th, 2012 the tenth and final technical meeting for the 2010-2012 season took place
in the auditorium of Maran Tankers Management, Inc, in Athens. Dr. Nikolaos Kakalis, Head of
Research & Innovation at Det Norske Veritas (DNV), Greece, presented the titled topic to more
that 50 SNAME members and guests.
Dr Kakalis first explained today’s shipping environment which is characterized, on the one hand,
by rising fuel costs, huge market uncertainties and market volatility rates and, on the other
hand, by a very demanding environmental regulatory regime. These are all driving the maritime
industry towards the adoption of more cost-effective and environmentally friendly operations
and technologies. However, these technologies are of increased sophistication and complexity.
Computer-aided methodologies can successfully address the increasing complexity of integrated
As he pointed out, a class of systems engineering methodologies have been developed by
DNV Research & Innovation. Dr. Kakalis presented the main methodology which includes the
1. Identify relevant system components
2. Mathematical model development
3. Computer code implementation
4. Model validation
5. Model library development
Then, Dr. Kakalis presented COSSMOS (Complex Ship Systems Modelling & Simulation), a
computer tool for integrated marine systems synthesis, design and operation optimization.
The potential of COSSMOS was highlighted via illustrative case studies including the dynamic
simulation of marine boilers and the optimal design of heat recovery unit to maximize total
efficiency for a 4,500 TEU containership.
In addition, a case study of the decision support for Crude-oil Discharge Operations (CDO)
of tanker vessels was also presented. The results of the performance assessment for the
optimization of tbe discharge operations of the crude oil carrier were based on onboard data
measurements and simulation using the vessel-specific model developed in COSSMOS.
Dr. Kakalis concluded his presentation presenting some preliminary, but very interesting,
findings on the impact on overall performance of marine scrubbers.
In the case study that was presented, the sea water scrubber on vessel having a two-stroke
slow speed marine diesel engine for main propulsion resulted in an increase of the fuel
consumption of approximately 8 – 9%. Their analysis also suggested that forced draft fans may
be used to mitigate the increase in consumption but this may increase the electric load needs by
approximatelly 4.5% to 6%.
After this presentation of significant current interest, a reception was held at an adjacent hall at
Maran Tankers, Inc.
From left: D. Economou (EC member); N. Kakalis (Author); P. Lalangas (Secr / Treasurer); G. Grigoropoulos (Ex-Chair).