  European climate polices acknowledge the role that energy communities can
play in the energy transition. Self-consumption installations shared among
those living in the same building are a good example of such energy
communities. In this work, we perform a regional analysis of optimal
self-consumption installations under the new legal framework recently passed in
Spain. Results show that the optimal sizing of the installation leads to
economic savings for self-consumers in all the territory, for both options with
and without remuneration for energy surplus. A sensitivity analysis on
technology costs revealed that batteries still require noticeably cost
reductions to be cost-effective in a behind the meter self-consumption
environment. In addition, solar compensation mechanisms make batteries less
attractive in a scenario of low PV costs, since feeding PV surplus into the
grid, yet less efficient, becomes more cost-effective. An improvement for the
current energy surplus remuneration policy was proposed and analysed. It
consists in the inclusion of the economic value of the avoided power losses in
the remuneration.
