Unravelling load patterns of residential end-uses from smart meter data

With increasing shares of intermittent renewable energy sources in the power mix, managing residential loads is seen as an emerging option for balancing supply and demand in the system, reducing the need for investments in additional electricity generation and transmission infrastructure. At the same time smart meters endow a growing number of utilities and system operators with detailed information on individual households' load profiles, but they usually provide no information on the actual end-use activities. Understanding residential electricity usage patterns, however, is critical for designing effective energy efficiency and load management programs. Thus, the aim of this paper is to elicit load patterns of individual end-uses from smart metering household data and to assess their implication for national energy system management. This paper combines half-hourly load records with survey data from 4,200 households participating in a representative smart meter project in Ireland to econometrically estimate end-use-specific load profiles, controlling for demographic and buildings characteristics. For each of nine ""typical days"", representing combinations of different seasons and days of the week, we estimate 48 reduced form electricity demand equations. It was found that distinguishing load profiles between workdays and weekends proved essential, in particular for electric stoves, dishwashers and TVs. Calibrating our estimated load profiles for five household end-uses to the actual load curve of Ireland in 2011, we are able to explain up to 40 % of the total system load. Our estimates imply that that lighting and electric account for about a third of the winter evening peak load in the Irish power system, but their load profiles differ substantially between seasons. To reduce the Irish system load peak energy efficiency policies should focus on lighting and thermal insulation. We find that energy efficient lighting and a wide-ranging technology switch from electric heating to heat pumps may lead to a reduction in the winter evening peak load by 17 %. Finally, policies promoting load-shift should address electric heating before targeting other end uses like driers or dishwashers.