Application evaluation of passive energy-saving strategies in exterior envelopes for rural traditional dwellings in northeast of Sichuan hills, China

With the increase of residents' requirements for the living environment, the current indoor thermal environment cannot meet the needs of modern rural residents who live in the northeast of Sichuan, China. Passive energy-saving strategies can not only improve the thermal performance of envelopes but also create high economic benefits. Evaluating the application effect of passive energy-saving strategies for traditional dwellings can provide a guide for local residents and policy makers to select rational passive strategies. Seven energy-saving strategies are proposed based on the current local building construction and heat transfer model, and then their energy-saving potential is evaluated by using EnergyPlus and the dynamic investment payback period method. Results show that adding exterior envelope insulation and setting on-top sunspaces on the roof simultaneously can save 83.9% of building energy consumption. However, the most economic energy-saving strategy is only employing exterior envelope insulation for local traditional dwellings when considering the economy. It can save 842 CNY/m(2) during 100 years and its dynamic investment payback period is 14.1 years. In addition, building orientation also affects the energy-saving effects and the energy-saving rate can be increased by 8.4% under the optimal orientation (facing south) compared with the worst orientation (facing west).