Residential Consumers’ Willingness to Pay for Sustainable Grid Resilience Against Climate-Induced Large-Scale Outages of Long-Duration: Evidence from South Korea

South Korea faces escalating climate change threats that increase the risk of large-scale outages of long duration. However, efforts to expand the grid are often limited by low consumer acceptance of higher tariffs. This study employs a nationally representative contingent valuation survey of 1000 households to quantify residential consumers’ willingness to pay (WTP) for grid expansion to avoid a hypothetical 24 h nationwide blackout caused by extreme weather. The findings reveal an average monthly WTP of KRW 2226 (USD 1.54), equivalent to about KRW 0.60 trillion (USD 0.4 billion) annually—approximately 12% of planned grid investment needs. Among the socioeconomic variables, the negative coefficient on generation suggests younger cohorts exhibit higher WTP, consistent with—though not conclusive evidence of—their expectation of greater exposure to future climate risks. Similarly, the presence of children is positively associated with WTP, indicating family protection motives that encompass both immediate household needs and intergenerational considerations related to the distribution of climate-related burdens. These findings provide policy-relevant insights for designing equitable and acceptable tariff schemes that support critical investments to strengthen sustainable grid resilience amidst escalating climate risks.