Effect Of Climate Change On Building Heating And Cooling Energy In Tianjin

As the economic centre of northern China, Tianjin gain high level of urbanization which promotes government to protect environment, save energy and improve living conditions. The energy security issues become increasing serious as energy consumption is increasing, especially extreme energy threat to energy consumption and construction equipment operation. It is analysis the effect of climate change on building energy consumption for providing science basis of energy program, energy strategy, energy consumption forecast.The study simulated heating and cooling energy of three kind of building type in Tianjin during1961-2009using energy simulation software. In addition, the relationship between building energy and meteorological data over the same period was particularly analyzed. The method of convention statistical, Mann-Kendall and multivariable regress were used to investigate the change of energy and extreme energy days, and the impact of climate on uncomfortable days and building energy and extreme energy days. The main results are as follows:(1) The mean temperature, minimum temperature, maximum temperature and wet bulb assumed increasing tendency in heating and cooling periods in Tianjin during1961to2009. Beside, the wind speed, sunshine duration and solar radiation had decreased. The abrupt point of meteorological factors actually showed up in the late1980s and early1990s.(2) The maximum temperature days had dropped significantly, and no significant variation was observed in minimum temperature days in Tianjin during1961to2009. The cold uncomfortable days were reduced and hot uncomfortable days were playing an advanced tendency. The significant correlation between uncomfortable days and mean temperature are appeared in heating period and in air-condition period also. The randomness of uncomfortable climate has increasing trend.(3) The heating energy of three kind of building type significantly decreased in Tianjin during1961to2009, while cooling load weakly with no significance at the0.05level. The main concentration of abrupt points occurs in the late1980s. The variations of heating energy were mainly affected by mean temperature that can account for99%of the heating load. In contrast, the effect of climate variables on cooling energy show month-dependence. Cooling energy of Jun. and Sep. was dominantly related to air temperature, whereas cooling energy was mainly in relation with wet bulb temperature and air temperature at Jul. and Aug.(4) The extreme heating energy days of building more significantly decreased and extreme cooling energy days had not changed significantly in Tianjin from1961to2009. Less extreme energy days occurred in transitional month. The contribution of extreme energy in the total energy showed large decrease in heating period, but it had changed little in cooling period in the past49years.(5) In Tianjin, the extreme heating energy days were mainly influenced by temperature, whereas the extreme cooling energy days were related to temperature, wind speed and moisture. Building energy-saving design and operation phases should therefore be made by fully taking into account of the difference in meteorological factors in the heating and air-condition periods.