Re-thinking energy justice to achieve a fair distribution of shared electricity from rooftop photovoltaics in a typical multi-apartment building in Germany: an interdisciplinary approach

Abstract

An important development in decarbonising energy consumption is the installation of shared rooftop photovoltaics on multiapartment buildings. It is widely agreed that the distribution of this relatively cheap electricity should be “fair” to all the users, and simultaneously maximise local use, to reduce global CO2 emissions and local electricity grid load. Most technical studies model or investigate distribution patterns on this basis, but without critical reflection on the energy justice issues that arise in sharing a common electricity source. This study brings together two distinct disciplines to move this discussion forward: technical issues in distributing shared photovoltaic output; and philosophical issues of energy justice. It sets this within Bhaskar's philosophy of interdisciplinary science which shows why narrow, highly specialist disciplines are necessary and why their findings must be brought together to inform us about the actual world we live in. On the technical side, the study models an apparently fair distribution pattern for a shared photovoltaic system in a case study multiapartment building in Germany. It then interrogates the outcome in terms of four different strands of energy justice philosophy: Rawlsian, Wittgensteinian, pragmatic, and “theological” (stemming from the environmental justice movement). It finds that Rawlsian concepts provide a basis for a just sharing pattern but with serious anomalies, while Wittgensteinian, pragmatic, and theological energy justice concepts provide avenues for these anomalies to be mitigated. This comprehensive cluster of energy justice approaches is therefore very useful alongside technical expertise, in the ongoing development of shared rooftop photovoltaics in multiapartment buildings.