ENERGY MANAGEMENT OF HISTORICAL BUILDINGS THOUGH AN AC-DC MICROGRID ARCHITECTURE, MONITORING AND CONTROL

Recently, the cost of purchasing electricity from utility grid has skyrocketed. Smart buildings, if optimally managed, can maximize self-consumption and minimize the purchase of electricity from the grid. Furthermore, through the application of control laws on the building’s energy resources, like boilers, battery energy storage systems (BESS), electric vehicles (EVs), photovoltaic (PV) and so on, it is possible to provide ancillary energy services to the grid which results highly profitable. Covid 19 Pandemic demonstrated the possibility of smart working and living far away from high populated towns, and perhaps more in contact with the nature, repopulating villages and hamlets which in Italy are rich of historical buildings and cultural heritage. The people in volved in this choice are interested in high quality internet-based services, environmental friendly use of resources, clean energy, electrical mobility, etc. Historical buildings present more issues compared to commercial and residential buildings in integrating RES, clean electrification and automation since the historical heritages need to be preserved and protected. In fact, the implementation of new electrical installations usually requires heavy and expensive renovation and often it is not possible in historical buildings due to some constraints oriented to protect it. Many appliances in these buildings can be supplied by DC (such as LED lamps, computers, video systems, etc.) as well as AC components (such as air conditioning etc.). The direct supply of DC through a DC nano-grid can increase the efficiency of the building’s electrical system, exploit local generation through RES (Renewable Energy Sources), save costs and reduce the impact of new electrical services on the public utility distribution system usually allocated in old parts of a town, villages, and hamlets characterized sometime by poor or old installations. Furthermore, the use of low voltage supply of DC - electricity in the building increases safety and reduces the impact of new circuits on the structure of the building through innovative conductive flat tapes, wi-fi services and building automation. A hybrid AC-DC nano-grid architecture without the need of redesigning the entire system is highly desired in these buildings. Moreover, the modernization of services in historic buildings for satisfying the taste of more sophisticated users can be facilitated by using new technologies, components and energy management systems based on cloud architecture, microcontrollers and multiprotocol gateways to cope with legacy devices. In this paper, optimal energy management based on a hybrid AC-DC nano-grid is proposed for historical buildings. The proposed optimization algorithm aims to maximize self-consumption, reduce the purchased energy from utility grid and cooperate with other buildings as in Energy Communities according to the actual European Directives.