Cyclone preparedness strategies for regional power transmission systems in data-scarce coastal regions of India

Abstract

As frequency and intensity of tropical cyclones, and degree of urbanization increase, a systematic strengthening of power transmission networks in the coastal regions becomes imperative. An effective strategy for the same can be to strengthen select transmission towers, which requires consideration of network at a holistic scale and its orientation relative to coastline, towers' fragilities, and cyclones' properties. Since necessary information is often missing, actionable frameworks for the prioritization remain elusive. Based on publicly available data, a representative fragility curve for the towers in the state of Odisha, India was developed. The state has a 485 km long coastline, and is subjected to cyclones routinely. The power transmission network in the state serves over 40 million people. Performance of the network under cyclones was quantified in terms of population affected. The performance was found to depend significantly on landfall location, and path traversed prior to landfall. The results highlighted the importance of performing such studies at a regional scale. Further, efficacies of strategic interventions in the network were evaluated. These interventions (72 considered herein) differ from each other in selection of a geographical region, basis for prioritizing the towers, number of towers to strengthen and extent of strengthening. Strategies that consider rather simplistic properties of the network and its orientation with respect to the coastline work much better than those based purely on the network's properties, in spite of minor variations in towers' fragilities. This integrated approach opens avenues for actionable engineering and policy interventions in resource-constrained and data-deprived settings.