RETRACTED: Unpacking the energy performance gap: Household variation in actual vs. theoretical heat demand in energy-efficient homes

The discrepancy between theoretical and actual heat demand - commonly referred to as the energy performance gap (EPG) - is well-documented across national contexts. However, less attention has been given to how this gap varies within energy efficiency classes and between household types. This study investigates the heterogeneity of the EPG in Danish single-family homes rated A2010 and A2015, using administrative data from 10,616 households. The dataset links Energy Performance Certificates (EPCs) with actual annual heat consumption data, covering both space heat and domestic hot water for the period 2019 to 2021.Results show significant variation in actual heat consumption across income groups, diverging substantially from the theoretical demand. For homes rated A2010, actual consumption ranges from 76.7 kWh/m2/year among low-income households to 84.0 kWh/m2/year among high-income households, which resembles an EPG of 67.4% and 83.4% respectively. Similar patterns are observed in A2015 homes. The results also showed variations across the variables, number of adults and children in the household, whereas the consumption patterns across years varied slightly.These findings highlight the critical role of household composition, occupant behavior, and socio-demographic factors in shaping actual energy use - even in highly energy-efficient buildings. The study underlines that energy efficiency alone does not ensure low energy consumption and that energy policies and performance metrics should more explicitly account for household-level variation.