Grid-consumer interoperability（GCI） implementation foundation and its effects on load curve in a smart grid are analyzed. Basically GCI is fuzzy and adaptive， as a result， it is difficult to quantitatively simulate GCI effect by traditional modeling technology. Intelligent engineering hybrid model is a promising modeling tool to address such difficulty. Based on the characteristics of GCI， an intelligent engineering hybrid model is developed. The model includes control center agent， generation agent and consumer agent. Consumer agent fuzzily inferences its electricity consumption behavior based on the fluctuation of real time price and the size of responsive load in the electricity market environment， then load curve is influenced further. Simulation on IEEE 39-bus New England system demonstrates the validity of proposed quantitative simulation approach and the intelligent engineering hybrid modeling technique.