Buildings with mixed residential and commercial units show relevant power peak that are further increased by shifting from gas-driven systems to 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 (BACS) 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 demand side management (DSM) for residential/commercial buildings. 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 the present paper, main aspects of the proposed control system are presented and simulations for a given case study with local PV 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 RES may be achieved.

The new challenge in power systems design and operation is to organize and control smart micro grids supplying aggregation of users and special loads as electric vehicles charging stations. The presence of renewable and storage can help the optimal operation only if a good control manages all the elements of the grid. New models of green buildings and energy communities are proposed. For a real application they need an appropriate and advanced power system equipped with a building automation control system. This paper presents an economic model predictive control approach to the problem of managing in a coordinated way the electric and heating resources in a smart building, for the purpose of achieving in real time nearly zero energy consumption and automated participation to demand response programs. The proposed control, leveraging a mixed integer quadratic programming problem, allows to meet manifold thermal and electric users' requirements and react to inbound demand response signals, while still guaranteeing stable operation of the building's electric and thermal storage equipment. The simulation results, performed for a real case study in Italy, highlight the peculiarities of the proposed approach in the joint handling of electric and thermal building flexibility.