A smart grid (SG) is a network of interconnected nodes that can generate, consume, and share energy. In this paper, we consider a game theoretic approach to its management aimed to balance the monetary and energy transactions between users. We analyze the efficiency of the proposed approach for a smart grid consisting of a set of prosumers connected to an energy router that manages energy and monetary transactions. We compare our game theoretic approach with alternative strategies available to a prosumer, i.e., to sell, buy or store the energy whenever possible. For each strategy, the monetary outcome was compared, showing some interesting results.