by Song Peijing

Special to the Tsinghua News Center

(Professor Jiang Yi with his students)

Large-scale public buildings have high energy density, which on average consume 5 to 15 times more electricity than residential buildings. In Beijing, those public buildings account for about ten percent of the total building area, but their energy consumption (except heating) amounts to more than thirty percent of the total. Few electric meters are installed in those public buildings, however, making it more difficult to monitor how the energy is used.

Recently, a new real-time monitoring and online analysis system to collect and analyse electricity consumption data from large-scale public buildings was successfully developed at Tsinghua’s Building Energy Research Center (BERC). The new system monitors the real-time electricity usage of facilities and equipment. Based on the collected data, unnecessary energy consumption can be identified and retrofits can be made to cut down on energy consumption.

(Online Benchmarking for Building Energy Consumption)

The system has been implemented already in more than ten public buildings with real economic benefits. For example, the system installed in one office building revealed that the air conditioner fans never turned off after they were installed. After some adjustments, 13,700 kilowatts of electricity were saved in just three weeks.

China has set a target of decreasing energy consumption per unit of GDP by 20 percent over 2005 in the next five years. Energy efficiency of buildings plays an important role in reducing China’s energy consumption. The director of BERC, Professor Jiang Yi, believes that the system will make a meaningful contribution to the above target and provide an important reference for better energy efficient building design.