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This paper considers the UL of a multi-cell multi-user MIMO network in which the BSs are distributed according to a homogenous PPP of intensity $\lambda$. Each BS is equipped with $M$ antennas and communicates with $K$ single-antenna UEs uniformly distributed within its coverage area. Coherent detection based on maximum ratio combining (MRC) is used at the BSs, based on CSI acquired from UL pilot signaling with each pilot symbol being reused in $1/\beta$ of the cells. In addition, we assume that the UEs are prone to practical transceiver hardware impairments and apply UL power control based on statistical channel inversion (with proportionality coefficient $\rho$), to resolve the near-far effects that otherwise would prevent communication [@Bjornson2016a]. Tools from stochastic geometry and classical statistics are used to compute a new lower bound of the average SE. This expression is then used to define the EE metric by also using the power consumption model developed in [@Bjornson2014b], which not only accounts for the radiated power but also for the operating power consumption required by (among others) analog transceiver chains, digital processing, and backhaul infrastructure.

Within the above conditions, an EE maximization problem is formulated under the assumption that a given average SE 