Impact of Power Outages Depends on Who Loses It: Equity-Informed Grid Resilience Planning

Abstract This research presents a novel approach for enhancing power grid resilience with a focus on social equity in light of increasing natural disasters. Utilizing a two-stage stochastic optimization model for flood mitigation investments, we optimize substation hardening and power flow decisions to minimize the weighted combination of expected load shed and expected equity metric. Our method uniquely approximates community power outages stemming from transmission grid disruptions, sidestepping the complexities of the distribution grid, and it incorporates two equity metrics (affected population and duration of loss) to address the uneven postdisaster well-being loss across communities. Our approach's novelty lies in integrating this equity-informed resilience model with realistic flood scenario generation and utilizing a large-scale synthetic but a realistic power grid of Texas. The findings highlight the importance of the composite objective function in altering power flow decisions to prioritize electricity provision and save communities in disadvantaged areas even without investing in substation hardening. The results also quantify the equity and load shed benefits of substation hardening as a function of the investment budget with a parameterized analysis. With an attention to equity, power outages increase in nonvulnerable communities — a trade-off made to mitigate well-being loss in the most vulnerable areas. We further explore a justice model inspired by the government's Justice40 initiative but find it less effective than our equity-informed models at preventing well-being loss. Our research, enriched by a comprehensive sensitivity analysis, offers valuable insights for policymakers, grid operators, and utilities aiming for a more resilient and equitable power grid.