The influence of Swedish households’ everyday activities and electricity-use patterns on the utilization of small-scale photovoltaic systems

Panel: Panel 7. Innovative buildings technologies

Authors:
Joakim Widén, Department of Engineering Sciences, Uppsala University, Sweden
Kristina Karlsson, Department of Technology and Social Change, Linköping University, Sweden

Abstract

Although many European countries have developed extensive subsidy programmes for photovoltaics (PV) and other small-scale technologies for electricity generation, the interest in such programmes from Swedish legislators has been low. Subsidies for grid-connected PV systems for public buildings have been offered, but so far no initiatives have been directed to residential buildings. A recent inquiry suggests net metering for small-scale electricity producers, which would improve the economics somewhat, but the PV electricity would still be several times more expensive than the utility electricity. Nonetheless, private initiatives have begun to emerge in which companies offer small, yet expensive, systems for photovoltaics and wind power to residential customers.

The purpose of this paper is to investigate differences in the load-matching capability of PV systems in a number of Swedish households. Seven measurement series of end-use-specific household electricity on 10-minute intervals are used, together with modelled PV generation with the same resolution. The households have participated in interviews that give insight into the routines and habits behind their electricity use. Differences in the daily distribution of loads are determined for various system sizes. The habits behind the electricity loads and the resulting differences in load matching are discussed based on the interviews. Considerable differences between the households are found both in terms of total daily load profiles and of end-use composition, and explanations for these findings are suggested by the interviews.