Calculation of marine air conditioning systems based on energy savings

Abstract

Efficiency) is the comparison standard of the manufacturers of contemporary ships. The standard is based on the application of a more modern design of the diesel engines, the wide use of waste heat and the efficient operation of the ship. In accordance with the Economic Operation, the need to evaluate the design of air conditioning systems has been identified in order to determine the possible savings, which are represented by a decrease in fuel consumption, as a result of: the significant impact of this consumption in the operation of the ship, the current high costs of this energy, the periodic increase in the price of the same, and the international policies for the reduction of emissions to the atmosphere and preservation of the environment. By means of the energy diagnosis of the air conditioning system it is possible to determine the possible opportunities of energy saving during the operation of the ship. The results indicate that the thermal load and the cooling capacity required by the air conditioned spaces have a difference between their maximum and average value of 14%. This justifies the need to use a conditioning system with a variable volume of air supplied to the air conditioned space.El desarrollo de la propulsión de los buques en los aspectos de Operación Económica, Protección del Medio Ambiente y Eficiencia de la Propulsión del buque (Triple E-Economy, Environment, Efficiency) constituye el estándar de comparación de los fabricantes de buques contemporáneos. El estándar está basado en la aplicación de un diseño más moderno de los motores (máquinas) diésel, en la utilización amplia del calor de desecho y en la operación eficiente del barco. En correspondencia con la Operación Económica se ha identificado la necesidad de evaluar el diseño de los sistemas de aire acondicionado con el objetivo de determinar los posibles ahorros, que se vean representados en disminución del consumo de combustible, dado por: el significativo impacto de este consumo en la operación del buque, los altos costos de este energético en la actualidad, el incremento periódico en el precio del mismo, y las políticas internacionales para la reducción de emisiones a la atmósfera y preservación del medio ambiente. Mediante el diagnóstico energético del sistema de aire acondicionado se puede determinar las posibles oportunidades de ahorro energético durante la operación de la embarcación. Los resultados indican que, la carga térmica y la capacidad de enfriamiento requerida por los espacios acondicionados tienen una diferencia entre su valor máximo y medio del 14 %. Esto justifica la necesidad de utilizar un sistema de acondicionamiento con volumen variable del aire suministrado al espacio acondicionado.Key words: Thermal load, solar radiation, life cycle cost, marine air conditioning.

Assessment of Final Space Cooling Consumption in the European Transportation Sector

“…Notably, regarding the ship segment, as mentioned in Section 2, the most relevant source was Lugo-Villaba et al, 2017, which provided results such as the energy consumption of a vessel AHU running for space cooling [53]. In this case, regarding the EFLHs computation, most of the data sourced through the Meteonorm software were gathered from on-shore stations [39].…”

“…Concerning the training sector, Rooftop AC systems with a range between 20 and 35 kW of capacity have been appointed as the most common cooling technology mounted on both locomotives and railcars [52]. Lugo-Villaba et al, 2017 broke down the ship's air-conditioning sector by investigating energy savings of the air handling unit (AHU) of which the maximum SC capacity has been assumed to be around 392 kW [53]. Lastly, regarding the aircraft sector, the air-cycle machine, which also pressurizes the cabin and is powered by the APU, has been appointed with a maximum SC capacity of 56 kW [50,51,54,55].…”

Energy, Economic and Environmental Effects of the Marine Diesel Engine Trigeneration Energy Systems

“…On the other hand, the heating load of the ship has been determined by its purpose, respectively prescribed microclimate of the contained commodities compartments, and of the navigation route, so that it is continuously changing according to which climate zone the ship is in [26]. Apart from the need to balance the heating load, it is necessary to create an appropriate cooling effect for balancing the cooling load [27], which is in almost all modern ships balanced by the compression refrigeration plant (CRP); this significantly increases the electric load, while the heating effect of the installed cogeneration plant is being considerably unexploited [28]. By the use of an absorption refrigeration unit (ARU) with thermodynamic mixtures of water-lithium bromide (H 2 O-LiBr) [29,30], and ammonia water (NH 3 -H 2 O) [31,32], and with negligible electrical load, the utilization of the cogeneration thermal output for a production appropriate cooling effect is allowed.…”