This chapter systematically elaborates on the global energy context, technical characteristics, and development prospects of nuclear power generation, emphasizing its core advantages such as high energy density, cleanliness, and abundant resource potential. It also explores the strategic role of nuclear power in china’s clean energy transition, aligning with the china’s nuclear development history and the “dual carbon” goals (carbon peaking by 2030 and carbon neutrality by 2060). The chapter analyzes the thermal system structures and operational principles of nuclear power plant (NPP) types, including pressurized water reactors (PWRs), boiling water reactors (BWRs), and high-temperature gas-cooled reactors (HTGRs). Based on thermodynamic principles, it introduces thermo-economic performance indicators (e.g., gross efficiency, steam consumption rate) and analytical methods, aiming to optimize energy conversion efficiency.