Energy Internet The Challenge of Smart Micro-Grids

Low-voltage distribution grids are experiencing an increasing proliferation of small-power energy sources (mostly PV units) owned by domestic end-users (prostumers, i.e., at the same time producers and consumers). The current regulations enforce prosumers to feed their generated energy into the grid, and to disconnect if the grid parameters (voltage, frequency) outgo a given interval. These simple rules, however, misbehave in a situation, as the one currently experienced in Italy, where the installed PV power amounts to 20 GW and exceeds 12% of the total energy production. A smarter and more efficient management of the large amount of small energy contributions powered by prosumers requires a radical innovation of the operation codes in lowvoltage distribution grids. In particular, implementing energy and data networking among the prosumers of a residential community allows the creation of smart micro-grids, which means sharing of resources among the entire community, trusted operation of the low-voltage grid, and aggregation of prosumers to empower their role versus other players of the electrical market (DSOs, utilities, traders, etc.). This gives rise to a new paradigm (the Internet of Energy) whereby communities of prosumers can implement peer-to-peer resource sharing, define common visions and strategies, organize themselves at various levels of aggregation, and play an authoritative role in the electrical market. Individually, each prosumer can benefit of: modulation of generated and consumed power along the day, to take advantage of hourly tariffs; unintemiptible supply of domestic loads, even in case of grid failure; improved stabilization of local voltage; capability to feed power on-demand, based on request conveyed by the smart meter. As a whole, smart micro-grids can provide: easy and flexible integration of renewable sources and storage devices; pervasive use of upfront ICT and power electronics technologies; reduction of carbon footprint; increase of distribution efficiency; savings for end-users and distributors; improved quality and reliability of electrical services; better exploitation of the electrical infrastructure. Moreover, the ICT platform will spur new services to the customers, and new roles and market shares for public administrations, utilities, traders, DSOs and territorial bodies.