Life Cycle Climate Performance Evalution Model For Mobile Air Conditioning System

Assessment of mobile air conditioning environmental (MAC)characteristic evaluation mainly concerns refrigerant’s GWP value, morethan the performance of refrigeration system. Actually the manufacturing,running and disposal of MAC system also affected energy consumption andthe environment. Therefore, a comprehensive evaluation index of airconditioning system named LCCP (Life Cycle Climate Performance and LifeCycle Climate) is introduced. This index includes the direct emission ofrefrigerant, and the indirect emission due to the production, transportation,operation and recycling of MAC system. Because of the index included manyaspects, and the data needed for the calculation is various and complex, thereis no a unified standard to get exact LCCP value.As the background of the cooperative project with SAE, this articleanalyzed items of LCCP, set up a LCCP model with a large number ofexperimental data and vehicle information. The model was available for212major cities’ climatic condition and driving condition. The environmentalperformance of new refrigerants and new MAC technology was compared byLCCP model and experimental research. The model provided tools for theselection of new refrigerant and the establishment of policy.The main content and achievement of this thesis are the following:1) MAC systems were analyzed comprehensively, the quality and typeof component materials, different refrigerant leakage and atmosphericbreakdown products, the coefficient of performance (COP) and parameters ofevaporator cooling capacity (Qe), the driving and climate conditions of eachcity were analyzed. 2) Data from13databases were collected, such as TMY3, IWEC, etc. Adatabase included the temperature, relative humidity, solar radition and otherclimatic data of212cities around the globe was established. Fanger thermalcomfort model was used to create a new method to calculate air conditongrunning time based on PMV-PPD.3) A LCCP calculation mathematical model available for worldwideclimate condition and multiple types of cars and different refrigerants on thebasis of Visual Studio software was builded. This model was proved toprovide human-centered interfaces, run quickly and produces acomprehensive and objective analysis of LCCP through the trial of more than20automobile manufacturers and air conditioning enterprises around theworld.4) The performance of R152a, R134a and50%/50%R152a mixturerefrigerant system were experimently investigated according to the strategyof China. LCCP model was used to carry on a quantitative analysis of thedirect and indirect emission and LCCP of different refrigerant systems. TheLCCP values of different regions using one kind of refrigerant were alsostudied. The LCCP values of R152a and50%/50%R152a system werelower than R134a system. The energy efficiency of MAC system is moreimportant than GWP value.5) Externally, internally controlled variable displacement compressorand fixed displacement compressor in automotive air conditioning systemwere investigated to introduce MAC energy-saving techonolgy in Chinesefourth stage fuel limit laws. The LCCP values were compared with the dataprovided by EPA (Environmental Protection Agency). The promisingtechnology were listed.This model has been spreaded globally by SAE as an industry standard.