Research On Evaluation Methodology And Performance Requirements For Cooling Source Of Air-conditioning System

In recent years, along with the grim situation about energy and environment, the government has paid more and more attention to this issue. China’s12th five-year plan takes energy and the environment issue as one of the three most important themes. At the same time, the government puts more efforts on energy conservation and emissions reduction gradually, and the requirements about building energy conservation are more demanding. As we know, energy conservation of non-residential buildings is an important part of building energy conservation in China, so energy standard for non-residential buildings is to be updated.In2012, MOHURD set the task about revising’Energy Standard for non-residential buildings’GB50189-2005edition. According to the revision task, this thesis mainly focused on how to evaluate the performance about the air-conditioning equipment and the demands of the energy performance.Firstly, this thesis made a research on evaluation methodology and Performance requirements for cooling source of air-conditioning system in different countries, and analyzed the application situation about IPLV (Integrated Part-Load Value) for chillers in China, and then pointed out the misunderstandings.Based on energy consumption simulation of air-conditioning system with multi-chillers as cooling source, it showed it is reasonable using both COP and IPLV at the same time to evaluate chiller’s performance. Then it introduced the background of establishing IPLV in2005and showed the necessity to revise the IPLV matrix, and established a new IPLV matrix.For the situation of multi-chillers used in a system, how to evaluate the chiller group’s performance was also discussed in this thesis. Bases on the supposed operation strategies, this thesis found out the principle between the number of chillers and the weightings of part-loads. Besides chiller condensers’inlet temperature change characteristics were also included. Thus the evaluation method for chiller group energy performance was put forward.Because of huge difference between climate zones, the way and the time of using air-conditioning equipment are quite different. In order to reach the same energy saving, the emphasis and minimum requirements of energy performance for equipment in different climate zones should be different. So, this thesis tried to set different requirements based on the use situation and energy saving goals for every climate zone.The article used target decomposition concept, based on the data from chiller manufacturers, established comprehensive mathematical models for chiller energy consumption and chiller costs, and established energy consumption and economic model for different kinds of chillers as well. With the help of building energy consumption software, calculating the cooling energy consumption of the whole building and the energy savings for different typical non-residential building models in every climate zone to get their SIRs (Saving to Investment Ratio) of different chiller performances. Then, take the integrated SIR as the target, each building got a desired performance index under the integrated SIR; finally use all the desired results of different buildings in a same climate zone for a same chiller type to get a weighted average index.For chillers designed in operation conditions different from standard testing requirements, this article found out an adjust method for the required values. And it is only applicable for water-cooled centrifugal chillers.Based on the survey data of building energy consumption, this article analyzed and discussed the feasibility of cold source SCOP (summated refrigerating coefficient of performance) and put forward some suggestions.