Optimization Analysis Of Public Building Energy Saving Design In Chongqing

Nowadays, air conditioning energy consumption takes over a large proportion in building energy consumption, and different air-conditioning design programs have a significant impact on the energy consumption of the air-conditioning system. In the design stage, there is no systematic and comprehensive optimization process for the design of the specific air treatment plan(except for the cold and heat source and water system). In this paper, the typical air treatment schemes are compared, and the specific form of the air conditioning energy saving scheme in the public building design while the optimization measures are put forward.In order to obtain the more accurate calculation results of building air conditioning energy consumption, DeST is chosen to be the calculating software. In this paper, the present public building features, considering the influence of the thermal performance of building envelope structure and main functional rooms on the building load, a variety of building energy saving design typical programs are put forward in the light of the present public building energy consumption features. The load characteristics of the architectural environment, which meet the requirements of room function, are predicted through numerical calculation. And the optimized scheme is confirmed comparing of typical parameters(such as the number of hours and the room load). In addition, with the indoor environment control, air conditioning unit, air treatment methods and other variables dividing the design stage, the air-conditioning system energy saving scheme is gradually confirmed. The system load under different design schemes is obtained through the calculation software of energy consumption. According to the system load characteristics of different design schemes, the optimization of system scheme and equipment configuration are confirmed, and the optimal design scheme of energy saving in the air conditioning system is obtained.Firstly, the optimal design of the building load is obtained through the comparison of the scheme. The main factors that affect the building load would be chosen from three types: building envelope, indoor thermal disturbance and air conditioning settings, the changing trend and degree of the effect on load of the building or main function rooms by the single factor was analyzed with sensitivity analysis method, and compared the significant of the effect on load of the building or the main function rooms by these main factors. Find out the key factors, and obtain the optimized design scheme. Analysis results show that the average sensitivity sorting of envelope impact factors on building annual load: window-wall ratio > external window shading coefficient> external window heat transfer coefficient> external wall heat transfer coefficient; the average sensitivity sorting of Indoor thermal perturbation impact factors on room annual load: personnel density > lighting power density; the average sensitivity sorting of design parameters impact factors on room annual heating load: design temperature in winter>fresh air volum> design relative humidity, the average sensitivity sorting of design parameters impact factors on room annual cooling load: design temperature in wummer > design relative humidity>fresh air volum.Secondly, optimal scheme of terminal HV&AC system obtained. According to main function room plans and using characteristics, full air system and VRV system were chosen. The design process of full air system is divided into two stages: HV&AC system form and air handling units, and put forward the scheme design of terminal HV&AC system in stages, analyzed the optimal scheme of next stage based on optimization results of previous stage. In the perspective of thermal comfort and functional requirements, took room satisfaction, system satisfaction and annual load as evaluation index to analyz, and get the optimal HV&AC system form. Air handling could be subdivided into fresh air plan, heat recovery and terminal reheat scheme, simulate the annual air conditions in AHU, assure the most energy-saving under the condition of meeting demands, to obtain the AHU scheme. Conclusion as follow: full air VAV system with constant fresh air volum, no reheat and sensible heat recovery, would used in supermarket and showrooms; full air VAV system with variable fresh air ratio, reheat volume of 1200 W and sensible heat recovery, would used in offices; VRV system with fresh air sent to indoor by fan and full heat recovery sould used in guestrooms.Finally, energy consumption model of the target building was established after the selection of conventional cooling and heating source units by DeST software, annual running energy consumption was calculated, the conversion power consumption per unit area is 43.77kW·h/(a.m2). Otherwise, compared the index of load per unit area and the conversion power consumption unit area with similar building in the current literature. The results show that the index of load per unit area and the conversion power consumption unit area of target building after design scheme optimized have energysaving benefit in some degrees, and the energy conserving potential of the optimal design scheme is verified.Reach the goal of building energy consumption perdiction and optimization by the analysis of energy conservation design of public buildings in stages, to solve the problem of inappropriate cooling and heating sorce units capacity and low operation load rate, which caused by large cooling and heating load index design and irreasonable AHU module design. Not only reduce initial investment, but also improve the energy using efficiency, excavate the most energy-saving potential of building. In the mean time, provide a reference for building energy efficiency management and control mode by considering the best way of building energy using, help designers evaluate the design scheme from the perspective of thermal comfort and energy consumption, offer constructive energy saving measures on AHU module configuration.