An investigation on life-cycle energy consumption and carbon emissions of building space heating and cooling systems

•Establish a carbon emission model for building energy system in life circle.•Compare and analyze the carbon emission of renewable energy system and district heating system in their life circle.•Give some advices about the carbon tax of China.

Building space heating and cooling system built-in the town's infrastructure is an important factors for building energy consumption and carbon emission source. In order to understand the roles of building energy system in the global warming, this paper established a mathematical model of energy consumption and carbon emission for the building energy system. Two district heating systems for residential buildings and nine space heating and cooling systems for public buildings were selected to analyze their energy consumption, carbon emission and economy based on a calculating model. The results showed that the two residential building cases B01 and B02 of life-cycle carbon emissions are 743.60 kg/m2 and 620.98 kg/m2, the public building cases B03∼bl1 of life-cycle carbon emissions are 800.15–1377.85 kg/m2. Equipment materials production, installation and maintenance phase embodied energy and carbon emissions proportion reached up to 6%∼14%, energy conservation and emissions reduction potential should not be neglected. The application of some renewable energy reaches a certain effect of energy conservation and emissions reduction in building, but the life cycle cost of emission reduction is much higher than carbon tax in China.