Demand Response and Renewable Energy Management Using Continuous-Time Optimization

Facilities with limited flexibility to schedule their power consumption, such as office buildings or commercial establishments, can be modeled as time-varying nondeferrable loads. In this paper, we propose a demand response strategy for a nondeferrable load facility with renewable energy harvesting and storage capabilities. We assume time-varying electricity prices, and devise a strategy to minimize the expected energy cost incurred by the facility over a finite planning horizon. Unlike existing works, we derive our results by using a generalized model for the energy storage device, which takes into account the nonlinear relationship between the discharging rate and the remaining charge. Moreover, we use continuous-time optimization to obtain explicit results, which are meant to reduce the computational complexity of existing strategies. Finally, we use simulations to show that the proposed strategy outperforms the state of the art, especially when the battery discharging model is strictly nonlinear.