In this work nets of active resources (AR-nets) are presented. This is a generalization of Petri nets (ordinary and Super-dual) with a single type of nodes and two types of arcs (consuming and producing). Each node may contain a number of tokens (resources), that can be consumed or produced by “firings” of other tokens (location of consumed/produced resources is defined by corresponding arcs). So, in this model the same token may be considered as a passive resource (produced or consumed by agents) and an active agent (producing or consuming resources) at the same time. The expressive power of AR-nets and two modified models is studied. It is shown, that AR-nets and AR-nets with simple firing are equivalent to ordinary Petri nets. AR-nets with simultaneous firing are strictly more expressive.