Transformation of the Energy Market in Poland in the Context of the European Union over the Last 20 Years

The transformation of the energy market in Poland over the last 20 years has been a process deeply rooted in European Union policies and initiatives, including emissions trading (EU ETS), climate and energy packages and the European Green Deal. Poland, historically dependent on coal, continues to struggle with systemic problems such as low grid flexibility, ageing infrastructure, high CO 2 emissions and the socio-economic costs of the transition in mining regions. The research methodology is based on analysis of reports, scientific articles, EU documents and statistical data. So far, there is a research gap in the research area, mainly concerning two problems. The first is the lack of a multifaceted, integrated analysis of Poland’s energy transition, taking into account not only technological changes and RES participation, but also systemic problems (infrastructure, policy, social acceptance). The second, in turn, relates to the need to identify the impact of EU regulation as a driving force, not just an obstacle. The objective of the article is to provide a comprehensive analysis of the Polish energy market in the context of the EU over the past 20 years, covering (1) systemic problems of the Polish power sector, (2) the impact of key EU initiatives and regulations, (3) the development of renewable energy sources, (4) the modernisation and digitalisation of the grid, (5) current and future market trends, and (6) the main challenges of the transition. The analysis shows that Poland’s electricity sector is still dominated by coal, but its share is steadily decreasing, from ~85% in 2015 to about 60% in 2023. At the same time, the share of renewable energy sources (mainly wind and photovoltaics) has increased from ~10% to ~27%. Nevertheless, the gap with the EU average remains significant.