In this section, we evaluate the performance of network cooperation for energy saving using the framework given in Eqs. 1–5. The geographical region under consideration is given in Fig. 1 with the coverage of three cellular networks’ BSs that overlaps with the coverage area of a WiMAX BS. It is assumed that the initial BS working mode vector is X = 1111. The system parameters are given in Table 1. The number of available channels in the cellular network and WiMAX BSs are chosen in a way that reflects the higher capacity of a WiMAX BS. The total number of available channels in the region are determined such that the peak traffic loads do not violate the target level of the call blocking probability. The different power components of the WiMAX BS are chosen such that it is larger than that of a cellular network BS, in order to reflect the fact that a WiMAX BS has more channels and covers a larger area than a cellular network BS. The value of α gives equal importance to maximizing the amount of energy saving and reducing the BSs on-off switching cost.