Effects of Energy Saving Measures for Existing Urban Residential Buildings Based on Thermal Simulation and Site Investigation of Energy Consumption

This is one of two papers that predict the effects of energy saving renovation measures for existing urban residential buildings. The previous paper predicted such effects based on thermal simulation, but the simulative outputs are not sufficiently convincing. So in this paper, the measures' effects will be further analyzed based on the factual electricity consumption from site investigation. Firstly, the monthly electricity consumption of the subject building was investigated in 2007/2008. Then, the factual heating and cooling loads were distinguished through climate analysis. Finally, assuming that the relative energy saving effects of the measures are the same in thermal simulation and in fact, the simulative energy saving effects were revised by applying the factual heating and cooling loads, followed by CO2 emission and cost for a 40-year residual life span. The results show that the simulative outputs were too exaggerated, and must be revised based on factual electricity consumption. From the viewpoint of reducing energy use and CO2 emission, it is worth renovating existing residential buildings with energy saving measures, however, the economic benefits following revision are negative because of the too cheap electricity price in China. Therefore the government should provide subsidies for the energy saving renovations of buildings.