The assessment of carbon dioxide emissions resulting from electricity in public buildings during their operational phase within the construction industry is typically conducted using the carbon emission factor approach. The power grid’s average carbon emissions factor serves as the basis for the calculation, which has a certain lag. To address this issue, this thesis seeks to find out the dynamic carbon emission factor that can reflect the differences in time and space through the carbon emission stream theory. From the ‘carbon perspective’, this paper centers on the impact of users’ electricity usage behavior on carbon emissions, and proposes a low-carbon demand response mechanism employing the dynamic emission factor as the reference signal. This method’s effectiveness is verified via simulation by comparing the carbon reduction effect with that of the demand response using price as the incentive mechanism.