The aim of the research, the results of which are used in this publication, was to identify the motives for mergers and acquisitions in the energy sector after the introduction of green economy elements in Western Europe. The mentioned region is the group of countries where changes related to the move to green energy are most visible (in addition to some countries from other regions, such as Singapore, New Zealand, or countries of the Arabian Peninsula). The research assumed the hypothesis that over the years since the Paris Conference the themes of mergers and acquisitions have changed from motives close to the views related to energy generation in traditional systems (black energy in large, monopolistic systems) to motives close to green energy (the research hypothesis). This was confirmed in the research, as business risk diversification (defined as diversification of the power sources from black to green) was the most popular M&A motive. In addition to emphasizing the direction of changes in the M&A motives, the authors of this study decided to check whether since 2015 (when the Paris Conference was organized) the motives behind the M&A transactions conducted by companies operating in the electrical energy generation sector have changed, making their motives close to the green energy dominant in Western Europe. Apart from verification of the abovementioned hypothesis, the aim of the research was to check whether there are any characteristic directions of changes in M&A motives across companies from particular Western European countries. The motives are changing from positional approaches to motives closer to resource approaches (green economy). The research used a critical analysis of the literature on the subject, a study that used desk research based on openly available sources and our own analytical tool developed for the needs of this analysis, which is the transformation of the concept of analysis of the M&A motives proposed in K. Borowski’s research: “The strategic development of the technology companies. The mergers and acquisitions perspective”.