Correlations in reliability assessment of agent-based ancillary-service coalitions

Due to changes in the electric power system, small, distributed units substitute conventional power plants with regard to energy supply. This also holds for the provision of ancillary services. To this end, agents that represent units form coalitions. In this paper, a method is introduced to assess such coalitions with respect of how reliable they can provide ancillary services taking into account correlations between units within a coalition. The method is supported by an exemplary case study.