This paper considers a heterogenous network HetNet where a macro base station (MBS) coexists with many small base stations (SBSs). SBSs can be deactivated and put to sleep to save energy and are equipped with two power sources, harvested energy (HE) source and a power grid source, where first the SBS will use its available HE to serve the associated users. Then, the SBS will request any shortage of its energy from other active or deactivated SBSs which have surplus of HE. Finally, if there is still shortage in energy, the SBS will use the power drawn from the grid. This transfer of energy is facilitated through the use of the promising technology of the smart grid (SG). We investigate the grid energy minimization problem by optimizing both the transmission power and activation/deactivation (Dynamic Sleeping) of the SBSs. Moreover, a decomposition of the problem into a convex optimization problem and users association according to the best SINR is proposed. Then, we derived a closed form of the optimal transmission power and use the IPOPT algorithm to find the Lagrangian variables. The results clearly show the advantages of our model operational strategy.