Case study on Analysing Whole Carbon Emissions based on Actual Energy Consumption in Existing Buildings

The recent IPCC 6th Assessment Report (AR6) introduced for the first time the concept of calculating carbon emissions over the entire life cycle of a building, i.e. including the embodied carbon (EC) emissions generated in the material production, construction, operation and maintenance, and decommissioning/disposal phases of a building. In this study, operational carbon emissions (OC) were calculated for existing buildings based on actual energy consumption, and embodied emissions (EC) were also calculated for the amount of construction materials initially used at the time of completion.

The Life Cycle Assessment (LCA) method was used to calculate total carbon emissions. As a result, the largest part of the life cycle carbon emissions of the building is the operation phase, which accounts for 84.47% of the total carbon emissions. The materials production phase was the second largest contributor with 15.12% of the total carbon emissions. Finally, we concluded that carbon emissions can be controlled not only by energy source, but also by whether a building is occupied or unoccupied.