In this paper, we consider the power efficient operation of a wireless Heterogeneous Network (HetNet). Reducing the energy consumption is crucial for a successful HetNet deployment, as the increasing number of distributed base stations (BSs) leads to significant economical and environmental concerns. For traditional wireless networks, power efficiency is achieved by designing the transmit strategies in a way that minimal amount of transmit power is achieved within the BS. However, the rapid penetration of renewable energy sources as well as the recent trend of powering the HetNet using smart grids require a fresh look at the well-studied problem. Meanwhile, increasing demand for powering wireless networks also introduces additional operational concerns for the power grid. In this paper, we show how to jointly model these two systems for power efficient operation. We formulate the problem as one that jointly minimizes the power loss of the distribution network as well as the total transmit power in the HetNet. We also show that the resulting problem can be implemented in a distributed manner when the network is divided into multiple zones. Numerical results corroborate several advantageous features of the proposed joint design as compared with the existing HetNet operation method.