In the smart grid, a neighborhood area network (NAN) is a part of the cyber-physical system that achieves two-way communications between smart meters and meter data management system (MDMS). In this paper, we study the energy efficiency issue for uplink transmissions from NAN gateways to the concentrator connecting the MDMS. Classical power control schemes targeting pure bits/joule energy efficiency for multiaccess wireless networks do not fit in well due to the stringent data rate reliability requirement caused by the massive amount of smart meter data. Therefore, we propose a hierarchical uplink transmission power control scheme for a NAN using a two-level Stackelberg game approach. Focusing on linear receivers, the Stackelberg equilibrium for the proposed game is derived. Numerical results demonstrate that our proposed scheme achieves both data rate reliability and energy efficiency.