Energy mix as the basic regularity of the principles of sustainable development

. Energy sources are a basic factor of economic development. Within the framework of the climate and energy policy of the European Union (EU), the rural areas that allow the use of renewable energy sources become more important. The aim of the article is to show the direct impact of contemporary EU policy in this area on the economic situation of states. At the same time, we are developing recommendations for the EU regarding future climate and energy policy by analysing empirical data developed by the world's largest organizations and institutions, such as the International Atomic Energy Agency, the World Nuclear Association, Eurostat and the International Energy Agency, and practices used by EU countries. The basis of the presented considerations and recommendations is a review of the subject literature and statistical analysis of empirical data. Conclusions are presented in accordance with the economic effectiveness of various energy sources and the principles of sustainable development.