Commercial buildings account for over 25 % of the total building area nationwide and exhibit higher carbon emission intensity than other building types. Retrofitting these buildings into virtual power plants (VPPs) offers a promising pathway to mitigate their carbon footprint. A technical and economic assessment method of the virtual power plants renovation in commercial buildings based on commercial buildings participating in carbon trading is proposed, exploring the transformation of virtual power plants in commercial buildings from a full lifecycle perspective. From an economic perspective, the analysis incorporates initial retrofit investment, operating costs, and revenue from carbon trading to evaluate lifecycle economic viability of virtual power plant renovation for existing commercial buildings. From a technical perspective, the characteristics of carbon emissions behavior in commercial buildings are analyzed, and the carbon reduction potential of existing commercial buildings throughout their entire lifecycle based on three types of transformation behaviors are evaluated: energy consumption, energy storage, and power generation in virtual power plants.The simulation results show that as the total cost of virtual power plant renovation in commercial buildings increases, the carbon emissions in the lifecycle of commercial buildings will also relatively decrease. It is necessary to balance the relationship between the two and ultimately achieve a win-win situation between the cost of virtual power plant renovation and carbon reduction in commercial buildings.The technical and economic assessment shows that the static investment payback period for the transformation of commercial building virtual power plants is about 4 years, which is feasible in terms of economy, and the transformation of commercial building virtual power plants has significant carbon reduction potential.Therefore, although a certain initial investment is required, the transformation of existing commercial buildings into virtual power plants is technically and economically feasible.