Analysis On Technical Route Of "Chongqing Design For Energy Efficiency75%of Public Building" And Energy Saving Index Of The Cold Source System

In2005our country implemented “Design standard for energy efficiency50%ofpublic building” and achieved remarkable energy saving effect. Chongqing does verywell in building energy conservation: in2006Chongqing implemented “Designstandard for energy efficiency50%of public building in Chongqing” and willpromulgate “Design standard for energy efficiency65%of public building inChongqing” right now. The energy requirements for public buildings will furtherenhance, and the trend to realize the energy saving75%has become. Energy saving75%will reduces50%building energy consumption compared with standard for energyefficiency50%of public building. This paper focus on two questions: one is how torealize energy efficiency75%of public building in Chongqing, or the technology routeof energy efficiency75%of public building；The other is energy saving design problemof air conditioning cold source system.From the intrinsic connection between the public building energy consumptioncomposition and main design effect factors of the consumption, this essay analyzed thetechnical route of publish building energy saving realizing the75%energy savingdesign target. Energy consumption of the ventilation and air conditioning system andlighting system is restricted by the energy saving design level and is the main part of thetotal energy consumption of public building energy consumption. The thermalperformance of palisade structure makes great effect on the energy consumption ofHVAC systems and lighting system.Compared with the energy50%standard, the article established a business, hotel,and office three typical public buildings model and made a dynamic simulation ofenergy consumption. It analyzed the contribution on reducing the cold and heatconsumption by changing thermal parameters of outer wall, roof, outside the window（or curtain wall） and the technology difficulty. Then it concluded the reasonable thermalparameters of the palisade structure: exterior wall take0.9W/（m²·℃）、roofing take0.5W（/m²·℃）、the window take2.1W（/m²·℃）、and the activities of shading（in WinterSc is0.73，in Summer Sc is0.22）. Using the above parameters can reduce publicbuildings in Chongqing cold and heat consumption of9%. Transition season reasonableventilation can energy saving and public building ventilation season ventilation canreduce by15%cold heat consumption in Chongqing. Using the most advanced lighting appliances, may reduce the lighting power50%⁶4%, and energy consumption oflighting and air conditioning can reduce8%of cold and heat consumption. Above threemeasures can reduce32%of cold and heat consumption. In order to achieve saving50%energy, HVAC system need to improve energy efficiency by36%, and Cold sourcesystem need to improve energy efficiency by36%.A research about the cold source system of120public buildings in Chongqing wasmade and results showed that currently the main emphasis of cold source system energysaving design is equipment selection; energy saving design of cold source system inoperation period is seldom reflected. The existing design index reflects the parametersof the device itself, it cannot response of the designer will and does not consider theactual operation conditions influence of energy efficiency.An analysis about the influence of cold source system was made and the mainfactors are energy efficiency of water chillers、operation mode of water chillers andenergy efficiency of auxiliary machine. Temperature of the cooling water makes a greateffect on energy efficiency of water chillers. Using "cooling tower+water chillers"system as an example and calculated the cooling water temperature of Chongqingpublic buildings in all of operation cycle, and through the experiment shows theaccuracy of the data.The cold source system design energy efficiency ratio SCOP_LV is proposed.SCOP_LV could limit the efficiency of the cold source system including the host andauxiliary equipment and all the equipment could run efficiently in the operation cycle.Theory calculation method of the SCOP_LV is given and according the requirement of the“energy efficiency75%of public building in Chongqing”, the limit of the SCOP_LV forthe air condition cold source system is obtained. Through a calculation，the specificcalculation and use process of SCOP_LV was showed.Through feasibility analysis, there is some request to meet the energy saving aim:①The development of water chiller technology;②Improving the transmissionefficiency of the cooling water pump;③Operation mode of cold source system shouldbe reasonable setting;④Design technology promote.