Implications of smart electric water heaters: a detailed analysis of load profiles and aggregated peak load

Electric Water Heaters (EWHs) are ideal devices for implementing cost-saving energy management strategies due to their storage capabilities. With the growing adoption of smart EWHs in households, it is essential to assess their real-world performance and its impact on the grid. This study analyses hourly load profiles from 4,500 smart EWHs across five price regions in Norway, offering valuable insights into their consumption patterns in relation to hourly electricity prices. Additionally, the study compares these load profiles with data from traditional, non-smart EWHs and the consumption of overall households with conventional EWHs. The findings show that smart EWHs are responsive to price signals and can help reduce electricity costs for end users, with savings in both spot prices and the energy component of the grid tariff. Furthermore, the results indicate that smart EWHs do not increase grid peak load, as the load is typically shifted to off-peak periods. These insights are also highly relevant to the broader European context.