Demand response has been identified as a solution to achieve more effective markets and facilitate the integration of more intermittent generations. This paper develops a model to estimate the influence of the potential demand-side flexibility on power generation systems. A case study based on the power system in Sweden shows that the exploitation of consumers' flexibility would lead to a reduction in total generation cost through the more efficient dispatch of generation resources. When the penetration of wind and solar power increases, the demand-side flexibility could enable a better utilization of these nondispatchable generation sources.