Renewable energy sources have great variations when generating energy. In the supply network, the electric flow must be constant and respond in times of increased energy demand. The Dutch Institute for Applied Science Research has launched a research project to halt the fluctuations of renewable energies. It has been proposed the ignition and shutdown of large cold containers of great energy consumption according to the fluctuations of energy generated by renewable energy sources and the energy demand of users. They say that this way they will save a lot of energy without making any investment.