Renewable energy is one of the most discussed topics nowadays, more so than traditional combustible energy sources and nuclear energy. There is an apparent need to study its public acceptance and the general public's knowledge about it, especially in the context of more advanced inventions, such as smart grids, energy storage, or photovoltaic inverters. In this research, the results of a custom survey and those of several types of public social media datasets were processed to gain insights into the acceptance and awareness of these technologies. The second aim was to investigate technologies and related public opinions about manufacturers. One social media dataset was processed by a novel technology based on automatic data collection from popular social media sources, blogs, forums and public news. All the collected and anonymized data were restored in a custom-made data lake (unstructured database) and analyzed by a natural language processing (NLP) engine to extract the required information. The results showed that the Hungarian public's knowledge differs from the European reference values by a very high percentage. A further goal for new research in the investigated area will be to achieve a business intelligence rated system in order to predict future trends and events. Since different methods provide results from different viewpoints, the conclusion is that combined analyses have to be used for investigating popular topics related to energy, such as various technologies, issues related to energy transition, or even car sharing services for a sustainable future.