From Lockdowns to Red Lights: Behavioural Shifts and Structural Breaks in Electricity Demand in New Zealand

The COVID-19 pandemic prompted governments worldwide to implement containment measures, disrupting economic activity and electricity demand. In New Zealand, two key policy frameworks-the Alert System and the COVID-19 Protection Framework (Traffic Lights)-were introduced over nearly 3 years. This study applies an augmented ARMA model, supplemented by descriptive analysis and cumulative sum tests, to estimate stage-specific associations between containment settings and changes in national electricity demand from 28 February 2021 to 31 July 2023. The ARMA estimates indicate that Alert Level 1 was associated with a 3% increase in electricity demand and the Red Light phase with a 2.5% decline. The two estimates were statistically significant at the 5% and 10% levels, respectively, whereas coefficients for the remaining containment stages were not statistically significant. Cumulative sum tests provided evidence of structural breaks during Alert Level 1 and the Orange Light phase. The study also documents a downward trend following the removal of containment measures and shifts in daily and weekly usage patterns, offering insights for electricity demand management, infrastructure planning and energy policy under future disruptions.