The role of the energy storage and the demand response in the robust reserve and network-constrained joint electricity and reserve market

•A robust power system model with joint electricity and reserve markets.•The operation cost of the system increased by 16 836 € with the new model.•The marginal cost of electric energy changed when the reserve market is considered.•The results showed that revenue of energy storage and flexible loads increased. Increase of the variable renewable energy sources in the power system is causing additional needs for the reserve in the system. On the other hand, the integration of energy storage and the demand response offers additional sources of flexibility in the system. Most of the current studies that model energy systems do not model the reserve market. Because of this, these studies eliminate the possibility to assess the full benefits of energy storage and demand response. The method proposed in this study enables the comparison between the two approaches and evaluates the benefits of energy storage and demand response for both approaches. The case study was conducted on the power system consisted of 13 interconnected nodes. The results showed that the operation cost of the system was 28.1% higher when the reserve constraints were imposed for the most pessimistic scenario. Moreover, the results showed that energy storage and flexible loads achieved significantly higher revenues when they were able to participate in the reserve market. The results indicated the need for the development of the reserve market as well as frameworks that will enable the energy storage and the demand response to participate in the reserve markets.