Abstract
Energy policy affects the functioning of the economic and financial systems of countries worldwide. This paper provides a theoretical overview of the economy−energy nexus and discusses the particular cases of the energy policy dynamics amid the sustainability goals. This paper integrates multiple perspectives on the energy−economy nexus, with a particular focus on the energy trilemma, 4As of energy security and PESTEL approach. This allows the development of a comprehensive framework for the analysis of energy security and the sustainability interaction. A review of manifestations of the different dimensions of energy security and sustainability is carried out to identify the most topical facets of the issue. Then, the cases of the selected European Union countries (Ireland, Greece, Denmark and Lithuania) are presented to highlight the effects and features of the recent energy policy changes there. Indeed, these countries apply a PSO levy mechanism on electricity tariffs and are diverse in their geopolitical situation, economic development, geographical situation and energy dependency level. The analysis of the situations of such different countries applying the PSO levy mechanism makes it possible to perform a broader and more in-depth assessment and comparison of electricity tariff regulations. Thus, the developed theoretical model is applied to identify the major outcomes of the energy policy regimes (with a focus on tariff regulation) in the selected countries.