Impacts of Energy Flexibility in Transactive Energy Systems with Large-Scale Renewable Generation

Abstract

Modern-day energy systems are evolving to be complex, interconnected, and transactive systems without clear demarcation between energy 'producers' and 'consumers'. This is aided by the large-scale proliferation of renewables (at a centralized scale and in more distributed settings, such as rooftop solar) and the growing potential for demand-side flexibility. In this paper, we propose a mathematical framework that considers the interaction of energy flexibility and renewable generation in a transactive power system, where a grid operator can secure both generation and flexibility (storage) from centralized and/or distributed assets. Our results, derived under network-abstracted settings, mathematically relate the system operating cost to the available flexibility capacity. In addition, our proposed framework also characterizes the inflection point beyond which further addition of flexibility capacity does not affect the cost of system operation. Furthermore, the relationship between the price spread in the grid, i.e., the difference between maximum and minimum prices over the time horizon under consideration, and the available flexibility is also commented upon. Finally, we demonstrate our findings on a modified IEEE 30 bus test network.