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This paper develops a probabilistic earthquake risk assessment for the electric power transmis- sion system in the City of Los Angeles. Via a dc load flow analysis of a suite of damage scenarios that reflect the seismic risk in Los Angeles, we develop a probabilistic representation for load shed during the restoration process. This suite of damage scenarios and their associated annual probabilities of occurrence are developed from 351 risk-adjusted earthquake scenarios using ground motion that collectively represent the seismic risk in Los Angeles at the census tract level. For each of these 351 earthquake scenarios, 12 damage scenarios are developed that form a probabilistic representation of the consequences of the earthquake scenario on the components of the transmission system. This analysis reveals that substation damage is the key driver of load shed. Damage to generators has a substantial but still secondary impact, and damage to transmission lines has significantly less impact. We identify the census tracts that are substantially more vulnerable to power transmission outages during the restoration process. Further, we explore the impact of forecasted increases in penetration of residential storage paired with rooftop solar. The deployment of storage paired with rooftop solar is represented at the census tract level and is assumed to be able to generate and store power for residential demand during the restoration process. The deployment of storage paired with rooftop solar reduces the load shed during the restoration process, but the distribution of this benefit is correlated with household income and whether the dwelling is owned or rented.
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Selection of multihazard-based damage scenarios for the Los Angeles water supply network
Earthquake damage scenarios are required to support design and analysis of spatially distributed infrastructure systems. In this paper we develop a computationally efficient set of damage scenarios for the Los Angeles water transmission system that considers ground motion and liquefaction. Each damage scenario describes one possible realization of damage to the pipe network and includes the corresponding multihazard scenario and an associated adjusted annual occurrence probability. Each damage scenario, which specifies the damage state of each pipe in the network, is defined to be physically realistic and consistent with the associated multihazard scenario. Together, when probabilistically combined, the set of damage scenarios with their occurrence probabilities matches the probabilistic hazard and component damage distributions. The scenarios are selected to be small in number so that subsequent analysis is efficient. We combine ideas from recently developed methods to generate sets of multihazard scenarios and damage scenarios for analysis of spatially distributed infrastructure systems. The method applied in this paper involves simulating multihazard, and a number of respective damage scenarios, and using an optimization to select a subset of damage scenarios and assign adjusted occurrence probabilities.
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- Award ID(s):
- 1735407
- PAR ID:
- 10338504
- Date Published:
- Journal Name:
- 2021 ASCE Lifelines Conference
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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