Paper: Modeling and scenario analysis of residential building energy conservation in cities of different weather

Abstract

Building models are used to predict energy consumption and CO2 emissions under current and future conditions and serve as a basis for building design. The most important energy saving potentials in buildings can be achieved by improving the thermal performance of building and the efficiency of the district heating system. This study investigated energy savings in buildings in cold and hot regions of China and Africa and developed a modeling approach for energy savings in heating and cooling of residential buildings. We have provided an overview of long-term scenarios for energy demand and carbon dioxide (CO2) emissions. Using the industry-renowned software RETScreen, parameter simulations and optimizations are performed over the three time periods (currently 2030 and 2050). As a result, it was found that energy consumption has also increased and the comfort level of high-rise houses is about 10–21% higher than that of cold regions. The comfortable temperature range in these different cities is between 20°C and 29°C. We have showed the difference between the observed values and the model simulations (model bias) for HDD and CDD in cold and hot regions of China and Africa. This model represents spatial patterns and scales observed in Harbin, Shenzhen and South Africa. These features are characterized by an increased north-south gradient in eastern China, a topographically dependent distribution in western China and an associated increase in average temperature. The most commonly used types of heating in residential areas are heat pumps (31%) and district heating (21%). This is also the preferred case for condensing boilers (17%). In non-residential areas, heat pumps (32%), district heating (27%) and condensing boilers (11%) are the most commonly used heating systems. The total energy demand in Africa and China will be increased from 2020 to 2050. It is expected that the total demand for primary energy in China will be 8770 Mtoe in 2050, which corresponds to an increase in demand for primary energy of 1.9%, while Africa will see an increase of 2.7%. Final energy consumption in China and Africa will be 5776 Mtoe and 970 Mtoe respectively.