This research is devoted to an overview of the use of system analysis in the context of green energy development in Ukraine. The article focuses on systems analysis methods as an important tool for solving complex problems related to planning, choosing between several alternatives, types of renewable energy, optimisation and implementation of projects in this field. An illustrative project example demonstrates the practical application of these methods. The article describes the process of completing the stages of systematic analysis, such as collecting and analysing information on the state of the country’s energy sector, building a production model for presenting knowledge based on the collected facts, necessary actions and proposals; forecasting and making the most rational decisions based on expert assessment and objective analysis methods. The article also explores the use of mathematical tools based on a systematic approach and methods of mathematical modelling.