Aggregation of Users in a Residential/Commercial Building Managed by a Building Energy Management System (BEMS)

Abstract

Buildings with mixed residential and commercial units show relevant power peak that are further increased by shifting from gas-driven systems to an electric source. The proposed solution is to organize a microgrid for such type of buildings, aggregating different users with a common electric distribution system with a single connection to the grid, a local common generation, and a common heating/cooling system (electric driven). This approach upgrades a group of independent small users with rigid loads and chaotic behavior to a large user with a flexible and controlled profile. A central building automation control system managing all built-in technical systems and smart appliances may control the load, minute by minute, shifting in time shiftable and controllable loads, and merging different kinds of loads, obtaining a flatter diagram. The authors consider the suggested approach convenient to realize a demand side management (DSM) for residential/commercial buildings. distribution system operator (DSM) exploits the flexibility of smart appliances and the thermal inertia of the structure, by imposing local and central set points of heating and cooling systems, according to actual global net load and generation at a given moment. In this paper, main aspects of the proposed control system are presented and simulations for a given case study with a local photovoltaic system generation are provided. Results show that this approach may lead to a power peak reduction up to 20% even in the unfavorable case of combining commercial and residential units. Moreover, full self-consumption of locally generated energy from renewable energy systems may be achieved.