Impacts of shading effect from nearby buildings on heating and cooling energy consumption in hot summer and cold winter zone of China

The authors studied five major municipalities (Shanghai, Wuhan, Changsha, Chengdu and Chongqing) in China's hot summer and cold winter zone, using eQUEST to perform numerical simulations of the effects of shading by nearby residences on electricity consumption for space cooling and heating. Space cooling demand reductions were as much as 10% to 20%, while space heating demand increases up to 20%. The shading effect from nearby buildings in the targeted region causes reductions in space cooling demand in summer, otherwise this effect outweigh increases in space heating demand in winter. In Shanghai and Wuhan, these two effects counteracted each other, but in Changsha, Chengdu and Chongqing, the effect of increased space heating demand in winter was barely discernible. The negative effect of shading in winter may be disregarded in the three inland municipalities (Changsha, Chengdu and Chongqing), designs may be proposed such that the shading effect from nearby buildings is maximized in summer. In contrast, for Shanghai and Wuhan it is probably more effective to design greater distances between buildings while applying a measure such as planting deciduous trees near the buildings to produce a shading effect from the leaves. Except in Shanghai, the highest reductions can be expected in residential building clusters designed with the suggested minimum distances between buildings. In Wuhan and Changsha, the current recommended minimum distances between buildings are favorable with regard to reducing electricity consumption for air conditioning. The authors extended the target region north and south (Ha'erbin, Beijing, Shanghai, Fuzhou and Haikou), examined the effects of differences in weather values on the calculation results.