Study On Impact Of Air-conditioning Energy Consumption On Office Buildings With Solar-reflective Wall In Chongqing

Since Chongqing became a direct-controlled municipality, the urban construction israpid developing and people’s living standards are improving, energy consumption ofbuildings rising, urgent need to seek suitable energy-saving technology for chongqing torealize building energy efficiency. Solar-reflective coating with high reflectancecharacteristics, its reflectivity is greater than0.8, the solar-reflective roof of officebuilding in Chongqing has achieved many effectiveness, can substantially reduce airconditioning energy consumption of the top floor rooms. Exterior wall as the mainchannels for heat exchange between building and the environment, enhance heatinsulation performance of exterior wall is critical to reduce building energyconsumption, improve the regional thermal environment. but the impact ofair-conditioning energy consumption on office buildings with solar-reflective wall inChongqing has few studies.Firstly, heat insulation and preservation mechanism of solar-reflective exterior wallis studied, using the theory of heat transfer and the solar radiation model to analysis heattransfer of the wall body, in turn, select a office building in Chongqing Jiangjin District,regards two west room of building, exactly same size and orientation, as the researchobject, the west wall of one room at floor3painted with solar-reflective wall coatings,another room at floor4which do not make treatment as the control group. the electricityconsumption of air conditioning and the western wall surface temperatures in summerand winter were measured by the micropower monitor and the infrared imager. Theresults show that office buildings which use solar-reflective wall in Chongqing canreduce air conditioning cooling power consumption0.066kWh/(d m2) in summer, butin winter increase air conditioning heating power consumption0.008kWh/(d m2)during the test.In order to study the energy saving effect of office building’s different orientationusing solar-reflective walls in Chongqing, solar-reflective walls which reflectivity from0.2to0.8of new office buildings and existing office buildings are selected as theresearch object, using the energy consumption simulation software—DesignBuilderv3.0to simulate the annual air-conditionding energy consumption of solar reflectivewalls. it is concluded that different orientation of office building using solar-reflectivewall can reduce the annual energy consumption of air conditioning room in Chongqing,, the energy saving rate of the annual energy consumption is different for the variousfacing exterior wall of new office buildings, the energy saving rate of the east wall is4.49%, the west wall is4.01%, the south wall is3.02%and the north wall is2.79%.For the various facing exterior wall of existing office buildings, the energy saving rateof the east wall is6.49%, the west wall is5.45%, the south wall is3.98%and thenorth wall is3.98%.The measured results show that solar-reflective wall in Chongqing office buildingscan reduce air conditioning power consumption in summer, while, air conditioningincreasing power consumption in winter is only about12.12%of air-conditioningsaving power consumption in summer. The annual energy consumption simulationshows that solar-reflective coatings on the east, west, south and north facing of wallhave greater potential for energy savings, especially in east and west walls. Thoseresults provides a favorable reference for future researches and applications ofsolar-reflecting wall in Chongqing.