www.astesj.com 83 Enhanced Ship Energy Efficiency by Using Marine Box Coolers Abdallah Aijjou * , Lhoussain Bahatti, Abdelhadi Raihani Laboratory: signals, distributed systems and Artificial Intelligence, ENSET Mohammedia, University Hassan II Morocco. A R T I C L E I N F O A B S T R A C T Article history: Received: 13 August, 2018 Accepted: 24 October, 2018 Online: 01 November, 2018 Climate change, increasing fuel oil prices and new international regulation on ship emissions lead to more focus on shipping fuel consumption and energy efficiency. There are various solutions for improving the ship energy efficiency. In this manuscript, we aim to present a real case of energy saving by adopting the central cooling system with box cooler on the ship instead of conventional system. The electric energy power necessary for operating the machinery cooling system of the ship is calculated for conventional cooling system and compared to the cooling system using box coolers in term of fuel oil consumption and CO2 emissions. This study quantified the fuel saving potential that could be achieved with use of keel coolers. Adopting central cooling with box coolers may contribute in reduction of fuel oil consumption and improving the ship energy efficiency. systems. should not contain citations. Keywords: Ship energy efficiency Box / keel coolers Central cooling Sea water pumping 1. Introduction The ship machinery is essentially composed by propulsion diesel engine, auxiliary engines for electric power production and boiler for heating purposes. Other auxiliary equipment necessary for the operation are also fitted such air compressors, air conditioning plant, steam condensers, hydraulic power pack for ship mooring and cargo operation etc. All this equipment produces undesirable heat and need cooling which remove excessive heat out of surfaces of material, safeguard the metal mechanical properties and keep the temperatures within the limits specified by makers for maximum performances during operations. The propulsion plant (mostly diesel engines) is the largest source of energy to dissipates by cooling system [1]. The cooling system is designed to covers machinery cooling needs when most of the equipment are in operation at its maximum powers. Safe margin is also added. When we look at the electric energy balance of various types of ships we notice that cooling water pumps are among the largest and the most equipment running over the time, since they are solicited either when the vessel is at sea or alongside. Therefore, cooling pumps are the largest electric power consumers on board and are accounted for 10% of the kilowatt- hour consumed. This fact explains why several researches dedicated to ship energy efficiency focus on cooling system components. These studies have focused mainly on improving the performance and efficiency of the conventional cooling system (piping and sea water pumps) i.e. [2,3,4,5] studies on energy saving by improving the pumping system, [6] diagnosis and corrosion protection, [7] cooling system reliability. Very few studies discussed the possibilities of elimination of sea water pipes and pumps from cooling system [8]. The use of box or keel coolers is one of the solutions available for the ship building industry. Adopting box coolers for cooling systems allows to eliminate the pumps, filters, valves and reduces the piping length therefore the installation is more simple and cheaper. In addition, elimination of these components will reduce also the cost of the operational maintenance. This paper aims to demonstrate the effect of box cooler use on ship energy efficiency hence after this introduction we give an overview of different ship cooling systems in section II, in section III box and keel coolers principles are described, in section IV we study an application of box cooler for real ship in operation. Conclusion is given in section V. 2. Ship machinery cooling system: There are three basic types of cooling system commonly used in the marine machinery on board the vessel. 1-Direct cooling system with sea water (Fig.1): sea water is used as cooling media for heat exchangers in open circuit. Sea ASTESJ ISSN: 2415-6698 * Abdallah Aijjou, Email: thalassa1310@yahoo.fr, Tel: +212 661 42 34 17, Advances in Science, Technology and Engineering Systems Journal Vol. 3, No. 6, 83-88 (2018) www.astesj.com Special Issue on Multidisciplinary Sciences and Engineering https://dx.doi.org/10.25046/aj030608