Here we examine how the temporal mean and steadiness of the hydrogen discharge rate of a metal hydride reactor (MHR) vary, when its exit-pressure is deceased quadratically with time. To accomplish this task, a mathematical model accounting for the hydrogen desorption kinetics of LaNi(5) and the mass and energy balance in a cylindrical MHR is solved numerically. The initial and final exit-pressures of the MHR are prescribed, whereas the "pressure-drop time" (t(PD), during which the exit-pressure is decreasing) and the initial exit-pressure drop rate ((p) over dot(e0)) are the control parameters. Results of a systematic parameter study indicate that, for a given t(PD), increasing (p) over dot(e0) generally increases the mean hydrogen discharge rate, while there is a particular (p) over dot(e0) that minimizes the variance of the hydrogen discharge rate. The MHR exit-pressure variation therefore can be "optimized" to discharge hydrogen with maximized temporal steadiness. Some other strategies for MHR performance improvement also are discussed here. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.