ABSTRACT
Energy systems termed critical infrastructure systems, in particular the electric power supply systems, are undergoing massive changes. These systems have always entailed a multitude of components interacting with each other and therefore are complicated. However, in recent years, there has been even tighter integration and closer coupling, resulting in complexity. This increases, for example, the amount of highly dynamic and nonlinear behavior and the number of potential regime shifts and of cascades with pathways for spreading disaster. This development is ongoing and enhanced by, for instance, the pervasive use of modern digital technologies for communication within a system and among its actors and for controlling sensitive grids by means of integrating the growing shares of energy from intermittent sources. Furthermore, there is an increasing dependence on societal, institutional, and organizational factors. As a consequence, maintaining the stable and reliable operation of such a complex sociotechnical system, which exhibits behavior that is hard to understand and tackle, becomes more and more challenging, particularly in light of the need to make decisions under conditions of uncertainty and/or ambiguity.
This contribution will first introduce elements of complexity and discuss whether the electric power system exhibits complex behavior and, second, address decision making for systems in transition under conditions of uncertainty and ambiguity and propose options for mastering complexity, including a paradigm shift to resilience, and, third, reflect on the current status of our ability to model and understand interdependent critical infrastructure systems and introduce a multilayer agent-based modeling framework, providing cases to illustrate it. This approach appears capable of realistically capturing the complexities of energy systems, including the influence exerted by both technical factors and nontechnical, human factors. Concluding remarks will follow at the end.
