This book chapter gives an overview of Type 2 Fuzzy Logic (T2FL) and its application in solar energy research. Through a comprehensive investigation, both the applications and limitations of T2FL in the context of solar energy systems are illuminated. It examines the role of T2FL methods in managing uncertainty and draws insights from contemporary academic literature. This book chapter contributes to a differentiated understanding of T2FL methods and their impact in the field of solar technologies. The chapter examines how T2FL helps improve the efficiency of solar energy forecasting models, overcome power control challenges, and improves solar system performance. Furthermore, the integration of T2FL with MCDM (Multi-Criteria Decision-Making) methods for evaluating renewable energy alternatives is discussed. By providing practical insights and addressing potential challenges, this chapter seeks to advance knowledge in these interrelated areas. The content presented here aims to provide valuable perspectives for both academic and professional audiences and to position the T2FL principles in the dynamic landscape of solar energy.  In summary, the holistic view presented here enriches the discourse on T2FL methods and highlights their importance in the specific area of ​​solar energy research.