Estimation of electricity supply restoration time with interdependencies under cascading hazard risk approach

Abstract

The electricity infrastructure network functions as a system with several components interconnected and distributed over a region. When subjected to earthquake and its related cascading hazards, the vulnerable components undergo systemic failure resulting in outage of services. Restoration of power supply depends on the availability of road access to the damaged sites and hence interdependent on the road network restoration. In this paper, we present a detailed method to estimate restoration time with interdependencies that can be integrated with a broader cascading hazard risk probabilistic framework, developed in an earlier study by the authors.

The probabilistic cascading hazard risk framework begins with modelling of primary (e.g. earthquake) and cascading hazards to generate likely damage response of distributed infrastructure networks by accounting for uncertainties via Monte Carlo simulations and supports propagating uncertainties systematically. While this approach can generate thousands of damage realisations, we describe the restoration time estimation approach, by focusing on one potential damage realisation of electricity network considering its interdependencies on road recovery time, which can be repeated for simulations. In this paper, two infrastructures from Napier city are modelled and generated potential service outage maps of electricity network for a given restoration time for road network. Work is underway to generate full suite of damage realisations and quantify uncertainties in restoration times of the considered infrastructure networks.