Are the relative variation rates (RVRs) approximate in different cities when the same energy-efficiency reform is taken to the same building?

On the assumption that the same envelope reform is made on two buildings located in 19 cities of China, America and Europe, this paper simulates the annual heating and cooling energy consumption before and after the reform with tools of DOE-2, DeST-h and the authors' characteristic temperature method (CTM), and makes further analysis on the relative variation rates (RVRs) of energy consumption. It can be found that the absolute reductions of annual heating and cooling needs may differ up to tens of times in different cities for the same buildings with the same energy-efficient measures. On the other hand, there is no obvious difference in initial investment for the same energy-efficient reform in various cities of a country or an economic district, therefore, the energy efficiency potentiality and economic value of the same reform are completely different under various climatic conditions, which illustrates that it is very important to harmonize the local climates when selecting an energy-efficient project in different locations. However, when the same measures are taken to the same building, the annual heating RVRs are approximate and the annual cooling RVRs are also approximate in different cities, which is the common rule of building energy efficiency.