Developing decarbonisation pathways in changing times for Irish homes

Decarbonising and improving the energy efficiency of dwellings is a priority for climate and energy policy. The analysis in this paper is carried out for Ireland, which has committed to ambitious legally binding climate targets. The Irish residential sector, which represented 22% of energy-related CO2 emissions in 2020, is characterised by poor thermal efficiency and high reliance on fossil fuels. The TIMES Ireland Model (TIM) is developed within a framework demonstrating cost-optimal pathways for energy supply, transformation, and demand sectors. The results show that deeper decarbonisation pathways require more thermal retrofits and electrical heat pumps, increasing the total cost of the energy system. The results in this paper explore the effect of internal temperatures, highlighting the importance of using empirical data for accounting for the rebound effect. Exemplifying the value of an integrated system modelling approach, deeper decarbonisation pathways place further costs on the electrical system.