Promoting green, low carbon and environmental protection of power and energy is the key to future energy construction and solving a series of global environmental problems. Firstly,aiming at the problem of clean energy supply potential assessment,the impact of clean energy on power system operation and the core factors that restrict the development of clean energy are analyzed.Then, based on the assessment of clean energy supply potential, a power system operation simulation method for multi type power supply coordination and interaction in wide area spare time scales is stuided, and a specific evaluation index system for clean energy supply potential is constructed. On this basis, taking the actual power system of a province in China as an example, the potential of clean energy supply under different evaluation dimensions is compared and analyzed. The analysis results show that the method can be effectively applied to the assessment of the power supply potential of clean energy in the provincial power system.