Assessing the effect of new control and payment methods on heating energy consumption and occupant behaviour in Chinese dwellings

Energy demand reduction has become a global issue involving all countries, including China. As major energy consumers in today s society, the need for buildings to be built and operated more energy efficiently is well recognized. In 1995, the national standard on building energy efficiency in China (JGJ 26-95) was refined and updated to become the new residential Buildings standard (JGJ 26-2010) published in 2010. In the new version, many changes have been made to support the construction of more energy efficient buildings in China. For example, in the new standard, all buildings are highly recommended to install personal control on the heating system, such as by Thermostatic Radiator Valves (TRVs), together with pay for what you use tariffs. Previous practice comprised uncontrolled heating with payment based on floor area. In order to reduce building energy consumption, Chinese government has revised the Chinese building design standard. In the new guide the use of individual room temperature control is highly recommended for new and refurbishment buildings. However, evidence to quantify the extent to which this improvement impact upon on the building energy consumption is currently lacking. This thesis evaluates the impact of updated building design standards on thermal conditions and energy consumption in Chinese residential buildings. In order to evaluate the impact on the building energy consumption, two types of residential buildings have been chosen, one complying with the old Chinese building design standard, while the other complies with the new standard. The study was carried out in seven apartments in each type of building, a total of fourteen apartments and comprised with a longitudinal monitoring of indoor air temperature, outdoor air temperature, window position and energy consumption of each apartment. The impact of the new design standard has been evaluated in relation to a number of aspects, that include building construction, indoor thermal environment, occupant behaviour, thermal comfort and building energy consumption. It is concluded that updating the building design standard has had a positive influence on the building conditions and energy consumption. Furthermore, a thermal comfort survey was carried out in both new and old apartments according to updated standards. The results show that the Predicted Mean Vote (PMV) model has a efficiently adequate predictor of occupants thermal comfort in both type of apartments. Thereby allowing confirmation that the new control refine did not compromise on thermal comfort. The percentage of acceptable of occupants is higher in new apartments compared with the old apartments.