A pumping energy savings estimator is provided which, based on valve opening data collected for a control valve of a pump-valve system operating in an industrial process, determines an actual maximum (Δporg, ˜50% open) of valve operating region of the control valve of the pump-valve system. User can select a new maximum (Δpnew, ˜70% open) of valve operating region for the control valve. Then the estimator, based on the determined actual maximum of valve operating region and the selected new maximum of valve operating region, energy saving potential (Δpsave) in the pump-valve system. The potential energy savings may be put into practice by replacing the original pump with a new smaller pump, or more preferably, replacing or processing the impeller of the original pump, such that the control valve will operate with the selected new optimal maximum opening of valve operating region.