Unpacking the mental health effects of energy poverty – implications of energy poverty metric choice for research and policy

Despite energy poverty affecting millions worldwide, we lack understanding of how different methodological definitions of energy poverty influence evidence on mental health outcomes. This study aims to improve knowledge in this regard. We compare two major approaches of measuring energy poverty (monetary and self-reported) to assess their immediate and long-term impacts on mental health. Monetary energy poverty measures energy poverty using income and expenditure data, while self-reported energy poverty reflects individuals' experiences of energy hardship. Using the Household, Income, and Labour Dynamics in Australia (HILDA) longitudinal survey, we analyse the impact of both energy poverty types on adult mental health. Our findings reveal that monetary and self-reported energy poverty affect different populations and have distinct mental health consequences. Interestingly, monetary energy poverty alone showed no immediate statistically significant impact. However, when combined with self-reported energy poverty, it showed in the poorest mental health outcomes. Self-reported energy poverty had both immediate and long-term negative effects on mental health. Additionally, the longer someone experiences energy poverty, the worse their mental health, regardless of the specific type. This study highlights the importance of standardised energy poverty definitions. Since different definitions documented varying impacts on mental health, using appropriate standards can optimize resource allocation strategies for interventions targeting specific populations most affected by energy poverty.