Solar policy and practice in Germany: How do residential households with solar panels use electricity?

A substantial amount of the over 1.5 million photovoltaic (PV) systems in Germany are installed in residential households. Among these households, those with the option of self-consumption, i.e., to consume self-generated electricity can reduce their electricity consumption, especially grid electricity, by load shifting and acting in an energy-efficient manner. We examined how electricity consumption is influenced by contextual and attitudinal factors. We administered an online questionnaire to 425 households with PV recruited from 15 PV-related web portals. The results showed that their electricity consumption was not lower than in other households, but environmental motivation was higher. Sufficiency attitudes and environmental motivation were predictors of engaging in energy-saving behaviors which in turn contributed to consumption reduction. Battery storage and automatic load shifting increased self-consumption. Evidence was found for a distinction between households with PV installation before and after grid parity was achieved, especially concerning moderation effects of the economic framework. To reduce electricity consumption, a combination of efficient technologies and more environmentally motivated energy-saving behaviors should be supported.