This paper aims to design a system that can enable optimal operation of the solar powered Membrane Distillation Si-Reactor (MDBR) water recycling plant. Optimal operation is described as maximization of the clean water produced while being a self sufficient entity in terms of energy. During periods of adequate solar radiation, the system will optimize production levels. When faced with inadequate sunlight, the system will focus on reserving sufficient energy for the survival of the essential microorganisms in the MDBR. Hence, uninterrupted plant operation during periods of unfavorable weather entails the management of a back up reserve. These engineering objectives are translated into mathematical functions that can be incorporated into convex optimization problems. The effectiveness of the control framework is demonstrated through simulation. (C) 2013 Elsevier Ltd. All rights reserved.