The trend in the energy market has led in the last few years the increase in demand (eg the spread of electric vehicles) and an increase in volatile renewable energy sources (PV, Wind, etc.), a reduction in the use of fossil fuels, that destabilize the grid leading to black outs. The electricity grid is developing in a distributed network, so the connected energy markets are moving towards a new decentralized structure, where renewable sources and storage facilities (EVs), will have a significant penetration and adoption by energy customers, with the intent to provide sustainable solutions.[1] Balancing the demand and supply of electricity, in a system dominated by random elements, such as solar and wind production that depend on weather conditions, combined with the highly variable demand from domestic users, must lead to a new model of consumers and producers at the same time that is the so-called Prosumer and will be a challenge of great importance. With this paper we want to verify how the smart communities, made up of Prosumers, within smart cities, are the key to the new electricity distribution, based on ICT, IoT and smart metering. A significant contribution will be provided by the Blockchain to make the energy networks and related economic transactions secure and reliable.