A Parametric Analysis for Short-Term Residential Electrification with Electric Water Tanks. The Case of Spain

Abstract

[EN] Buildings are great contributors to global GHG emissions, because they are responsible for direct and indirect emissions. In light of increased renewable energy share in the electricity mix, it is crucial to boost residential electrification for building decarbonization. Consequently, building regulation ought to send the proper signals to the market to encourage electrification and avoid establishing new fossil fuel-based infrastructure, which may lock in future interventions and seriously compromise climate change mitigation. This paper studies short-term residential electrification with electric water tanks in Spain using a parametric analysis considering several water heater configurations with various sizes and management strategies, using different draw-off profiles, actual time-dependent electricity prices, and CO2 factors. The results demonstrate significant GHG savings when substituting fossil fuel boilers for any water heater configuration. However, current electricity prices are such that technology change is only cost effective for low hot water demands (1-2 people) and the provided fossil fuel supply is completely removed from dwellings. The exploitation of implicit demand response increases cost-effectiveness. The analysis of Spanish regulation shows that some elements of current policies on energy efficiency in buildings hamper residential electrification, consequently policy changes are proposed.