The massive impact of the wind and PhotoVoltaic (PV) power on the power systems require new approach and strategies, because of their unpredictability. This large expansion has been due to the feed-in tariffs, financial support and a concentration of R&D activities. Moreover, the distributed energy sources require a pervasive and complex management of the energy exchanges. Until now, the management has been usually based on a central authority, but new paradigms based on the BlockChain (BC) technology are very promising. This approach can also be useful to manage the peak power as well as the Demand-Response (DR) strategies. The paper presents this challenging tool for the current energy transition, highlighting the intrinsic features of the blockchain technology and the opportunities for the future energy systems, e.g. the execution of smart contracts in Peer-to-Peer (P2P) networks. This approach will become increasingly useful to manage the energy exchanges in new contexts, where the number of prosumers and active users is growing. The paper also proposes an application of the BC to manage the peak demand, using the energy injected into the grid by the electric vehicles.