Risk-averse strategic participation of prosumers coalition in local community markets

Local energy communities emerge as a valuable framework to optimally leverage local assets installed by prosumers. In this context, local markets launched within communities may boost the active participation of endusers, paving the way to improve the economy and energy efficiency of distribution systems. This paper proposes a new model for strategic participation of prosumers in local markets. The new proposal contributes with two main novelties. Firstly, the model considers the participation of prosumers coalition rather than individual participation. Secondly, a risk-averse resolution mechanism is developed, considering different uncertainty modelling for community and coalition-level uncertainties. Thus, whereas stochastic programming is considered for community-level uncertainties, robust optimization leverages better estimation of the coalition-level uncertainties. The optimization model casts as bi-level framework, which is further converted into a tractable single-level model. Some simulations are presented on a benchmark 15-bus community, involving eight prosumers, with three of them forming a coalition. Results show that coalition-level uncertainties impact further the economy of the coalition, incrementing the expected expenditures by 31 % versus 3.1 %. Moreover, the importance of flexibility provided by storage systems and controllable appliances is illustrated and discussed. In particular, neglecting storage capability increments expenditures by 30 % while flexible appliances contribute to reduce the coalition cost by 8.7 %. Further sensitivity analyses are performed regarding local demand and photovoltaic generation, as well as confidence interval and coalition sizes, showing that the developed approach performs well in a wide variety of scenarios.