Impact of modelled global solar radiation on simulated building heating and cooling loads

Two-parameter regression models were used to predict global solar radiation (GSR) for the nine major thermal zones and sub-zones – severe cold (I, II and III), cold (I, II and III), hot summer and cold winter, mild, and hot summer and warm winter – across China. The impact of using modelled GSR on building energy simulation was investigated. A total of nine cities were selected, one for each thermal zone. Generic office buildings were developed for each of the nine cities according the local design/energy codes. Two sets of energy simulation were conducted for each city, one with the measured GSR and the other the modelled data. The computed results were analysed in four aspects – solar heat through the windows, building heating loads, building cooling loads and the corresponding building energy consumption. It was found that simulated annual heating/cooling loads could differ by 0.1–6.2% and total building energy consumption 0.1–1.2%. These differences were also compared with the mean bias error and root-mean-squared error of the modelled GSR.