Conference Agenda

When exposed to heat waves, air conditioning (AC) serves as the primary means of preventing heat-related health risks, including mortality. However, surges in cooling demand can disrupt the balance between electricity supply and demand, potentially leading to large-scale blackouts. This study examines households' cooling demand during an extreme heat wave in California in September 2022. During this period, a 10-day event drove electricity demand to historic highs, bringing the state government close to implementing rotating outages and ultimately leading to the issuance of an emergency alert to conserve electricity. We analyze this event using large-scale, high-frequency data from networked thermostats. We first investigate the sensitivity of AC usage to extremely high outdoor temperatures by regressing AC usage for more than 10,000 households on temperature bins up to 110°F. Our results indicate that cooling demand continues to rise with temperature, even at extremely high temperatures. This increase is likely driven by increased air conditioner operation, rather than by active human behaviors such as setpoint overriding. These patterns suggest that many AC systems are oversized. We then evaluate household responses to the government request to save energy, which targeted hot and populated counties. To credibly compare targeted and untargeted households, we apply a matching difference-in-differences approach. Our estimates indicate that AC usage is not responsive to the government's request, and the reduction in its usage is small. These findings underscore the challenges of maintaining the balance between electricity supply and demand during future, more intense heat waves.