The new resources available in power system require a new agent to manage these resources in the most efficient way. Resources provided by the supply side or the demand side can be managed together in order to provide some services to the grid. New resources such as massive electric vehicle and distributed generation have been being gradually integrated to the grid and for the next years the integration tendency will follow increasing. These resources require a different approach to be managed adequately. The integration of intermittent resources into the grid is a challenging area but these issues can be addressed by an aggregator agent. On the other hand, the demand of power required by electric vehicle integration can impact the load curve of different distribution system far from its capability. An aggregator agent also can be useful to manage adequately the demand required by Electric Vehicles. This paper proposes an energy aggregator model (EAM) to manage power transactions between the grid and the demand side resources.