In the modern world, energy systems are undergoing major changes with the development of information technology. Thus, electric power systems are achieving significant success with the introduction of information and communication technologies. New measuring instruments, distributed energy monitoring systems, and new measuring instruments are being installed, which are subjected to high-frequency, large-scale information processing, which leads to a rapid increase in the volume of information in the field of electricity production and sale. Big data is collections of data that are extremely large, complex, and growing rapidly—they cannot be processed by traditional data processing software. The article discusses the use of big data analytics in electrical networks and its future potential, describes the main sources of information in thermal power plants, and the type of data. The role of big data in potential applications related to emergency analysis, pre- and post-accident assessment, safety assessment, and the use of various renewable energy sources is described. The article analyzes the possibilities of using big data in thermal power plants (TPPs). Ways to eliminate obstacles to the successful use of big data (BIG DATA) technology have been proposed.