Field tests to examine energy saving effects of occupants' thermostatic radiator valves (TRVs) regulating behavior in district heating systems.

Residential thermostat control is considered to be an effective way to allow individual regulation, and to encourage energy saving behavior. However, energy savings resulting from occupants' regulating behavior still needs to be quantified. We investigated several district heating systems that had thermostatic radiator valves (TRVs) installed, in Beijing and Tianjin, and evaluated the energy saving ratio, and the influence of heat transfer from adjacent apartments for four typical regulation scenarios. To separate out the effects of the occupants' regulation, a reference analysis method is proposed for comparison. Results indicate that when an individual occupant adjusted the TRVs according to a daily schedule for intermittent heating, the energy saving ratio was only about 6%. When the TRVs of an apartment are kept closed for a long unoccupied period (more than 4 days), the daily energy saving ratio was about 20%, and the total quantity of heat transferred from adjacent apartments was about 80% of the heat consumption of the reference apartment. In addition, when the TRVs were kept at a set-value (such as 3), energy saving ratios of about 12% were obtained. The results of this study provide further data for developing better management policies for heating terminal customization. [ABSTRACT FROM AUTHOR]