Fair and Optimal Investment Strategies for Renewable Energy Comunities

Energy Communities promote local investment in renewable energy sources through their local valorisation by benefiting of the complementary behaviours of the members. Furthermore, members of such communities may take advantage of additional investment options, i.e., joint investment, allowing low-income members to directly participate and benefit of the installation in the latter case. To ensure the sustainability of the investment and engagement of the end-users in local exchanges, the internal market design (i.e., sharing rules and prices) must be adequately designed along with the resources capacity. In this perspective, we define an innovative Multi-Objective Mixed-Integer Linear optimization framework which sizes renewable production means and storage systems and prices local electricity in order to find the best trade-off between collective economic performances, i.e., energy bill reduction, and individual cost savings repartition among the members. A sensitivity analysis on the weights of both objectives is realised and the impact of those on the investment strategies are compared. In addition, the propose approach is compared to state-of-the-art techniques such as sequential sizing then pricing methods or dual pricing techniques. Finally, the scalability of the model is discussed by considering two mixed (i.e., industrial and residential members) energy communities of different sizes.