Research on residential thermal environment differences in relation to transition and heating periods in Beijing

Abstract

In Beijing, municipal central heating is normally scheduled from 15 November each year and energy consumption for space heating is growing rapidly. This field study aimed to investigate residential thermal environment and its effects on subjective thermal responses and behavior adjustments in cold climate. The investigation was conducted in 12 apartment houses in six communities in Beijing from October to December 2019, involving both transition period before the space heating and heating period after the space heating. Indoor environmental parameters were collected by self-recording instruments, while heating equipment, subjective evaluations and adaptive behaviors were obtained though paper questionnaires. The results demonstrated that average air temperature in bedrooms of transition period was 19.5 ± 1.3 °C, significantly lower than 22.9 ± 1.9 °C in heating period. Moreover, there are large variations in indoor thermal environments among the heating systems/equipment. During heating, the interior air in houses was overheated (>24 °C) and low humidity(<30%) for 28.2% and 40.6% of the time respectively, especially above 30% of physical data measured were in prefer-warmer comfort zone, resulting in energy consumption waste and thermal discomfort. Although some of the indoor climate distributions in the transition period were out of the comfort zone, the residents reported that indoor thermal environment was still acceptable through adaptive behavior adjustment. This paper could be beneficial to the design and operation of reasonable heating temperature for both building energy saving and thermal comfort.