Impact of urban heat island effect on building heating intensity in Tianjin, China

The impact of urban heat island (UHI) on heating intensity of buildings was analysed based on the observed hourly temperature data during the heating periods from 2009 to 2017 in Tianjin, China. The results showed that the average annual heating intensity decreased 8.08% and 10.30% with the temperature in the urban centre increasing 1.46°C and 1.90°C compared with the suburban and outer suburban areas. The differences in the hourly mean heating intensity (HMHI) between the urban centre and the outer suburban areas reached its peak at 07:00 AM in the whole day, with the HMHI decreasing from the outer suburban to the urban centre. Overall, it is important to take into account the impact of the UHI effect on hourly variation characteristics of the heating intensity because energy use might be overestimated or underestimated at different times and urban areas if ignoring the UHI effect.