Investigations of Nearly (net) Zero Energy Residential Buildings in Beijing

Zero energy buildings have attracted more and more attention recently in the world. This research work studied the feasibility of a 12-storey plank-type building achieving zero energy. The study used Software TRNbuild to establish a 12-story residential building, as a reference building, based on DB11/891 - 2012(Design Standard for Energy Efficiency of Residential Buildings of Beijing). On the one hand, the study does passive building design, including high performance envelope, air-tightness and fresh air heat recovery efficiency, to reduce heating and cooling load. On the other hand, TRNSYS was used to simulate building energy system, such as solar domestic hot water systems (SDHW), unitary air-source heat pump for space heating and cooling, and renewable electricity system-PV. Annual energy consumption of reference buildings (central heating system for heating, ASHP for cooling) is 30.33 kwh/(m²•a). By contrast, that of NZEBs(ASHP for heating and cooling)is 11.1 kwh/(m²•a), declining by more than half. PV array production on the roof can meets its energy demand. If domestic hot water energy consumption is also included, PV array production on the roof can offer 95.8% of total electricity demand. In general, it's entirely feasible for residential buildings in Beijing to achieve nearly zero energy.