Private and social mitigation costs of the main clean energies for electricity generation in China are assessed here. Inputs and outputs for different technologies are calibrated based on the 2007 Chinese IO table and empirical data. Then, a hybrid CGE model is constructed to simulate the scenarios. The conclusion is that, instead of simply set emission targets for power companies, the regulator should induce them to adopt those technologies with lower social costs, such as hydro, bioenergy, wind, solar PV, be cautious about nuclear power plants, and avoid to use gas turbines for carbon reduction.