Collective self-consumption: the next step in PV prosuming policy to foster citizen engagement?

To integrate PV electricity into the grid, the self-consumption of PV-generated electricity is stimulated more and
more. PV self-consumption policies have always been aimed at the individual household. More recently, the idea
of collective self-consumption has risen, reflecting the EU's emphasis on the importance of energy communities.
Multiple households could form an energy community in which individual households are united and are able to
purchase electricity collectively and invest in energy technologies collectively. Comparing individual to collective
PV self-consumption stimulation, the latter entails that also directly consuming electricity generated by your
neighbor would be remunerated. In this study, we evaluate three versions of PV self-consumption policies:
individual, collective on the building level and collective on the community level. We find that when households
and their PV systems are aggregated, the optimal PV size increases from 0.65 kWp per household with individual
self-consumption to 1.5 kWp per household with aggregation on the building level and 1.95 kWp per household on
the community level. With self-consumption on community level, positive Net Present Values are found for PV
system sizes up to 10 kWp per household. Our results show that subsidy-free and grid-friendly PV policies can go
hand in hand with further deployment of PV and increased citizen engagement via energy communities.