The deregulation of electrical utilities brings about challenges and opportunities for the operation of large commercial and industrial facilities. Demand-responsive technologies such as thermal energy storage hold the promise of giving facility managers the tools needed to benefit from the imminent changes. This talk will discuss the merits of predictive optimal control for thermal energy storage systems under real-time pricing (RTP) and other dynamic rates. A line between utility rates with and without demand charges will be drawn to discuss appropriate optimization techniques and their applicability to real-time optimization. Time permitting; a simulation environment will be presented, which allows the convenient assessment of relevant parameters and graphical representation of results.