Regional breakdown of New Zealand’s residential heat demand and associated emissions

Quantification of heat demand at regional levels is critical for effective decarbonisation initiatives. We use a top-down approach based on climate zones, dwelling and heating-type statistics to estimate the regional breakdown of New Zealand’s residential space and domestic water heat demand. This is further broken down by fuel, enabling the calculation of associated greenhouse gas emissions. The breakdown shows excellent agreement with measured regional electricity consumption. In contrast, a breakdown based on population can overestimate and underestimate greenhouse gas emissions by up to 40 % and 60 %, respectively. The results identify regions with high emission intensity for focused interventions and more detailed planning. We also explore a future scenario where all space and domestic hot water heat is provided by heat pumps. This highlights regions with the most potential for emission reductions and quantifies the impact of greater electrification of heat on local electricity grids.