In the twentieth century, the developed energy system was based on the use of fossil fuels, essentially without limiting the production of energy or the use of resources. In the twenty-first century, faced with serious challenges caused by climate change, the functioning of the energy system must be fundamentally changed. New concepts such as demand-side management and energy storage in batteries are emerging, and the need for energy system balancing has increased significantly. When looking for opportunities to implement energy transformation, the use of existing infrastructure can significantly contribute to the speed of implementation of the transformation.