The Virtual Power Plant (VPP) is a feasible alternative for the integration of Distributed Energy Resources (DER) in the Electrical Power System (EPS). It controls the operational management and allows the commercial participation of each generation unit, regardless of its capacity, geographic location or grid voltage level. 

The main objective of VPPs is to increase the visibility of DERs to the system operator, and to allow small plants to commercialize their energy and even to offer power and ancillary services for the stability of the grid.  In this paper, we contrasted the theoretical VPP concepts with the results obtained in several projects developed around the world, demonstrating VPPs’efficiency in guaranteeing flexibility to the EPS.