Integrating economic and engineering models for future electricity market evaluation: A Swiss case study

The addition of stochastic renewable resources within modern electricity markets creates a need for more flexible generation assets and for appropriate mechanisms to ensure capacity adequacy. To assess both of these issues, more cross-platform analysis is needed that can evaluate short-term reliability concerns, medium-term dispatch and price concerns, and long-term capacity expansion and market design concerns. We present an integrated modeling framework that combines a long-term investment model, a robust dispatch model of the energy market, a detailed AC network model, a novel quantification for reserves, and a rigorous evaluation of renewable energy resource potentials. We apply the framework to a business-as-usual reference case simulating the phase-out of nuclear capacity in Switzerland and a case with renewable generation targets for Switzerland. We find that the nuclear phase-out leads to a strong increase in Swiss imports. In contrast, additional renewable targets lead to a decrease of these imports. In both cases, the Swiss cross-border lines are found to be the most critical network bottlenecks and in both future cases the increased reliance on imports worsens the severity of these bottlenecks. However, the network and security assessments show no significant challenges associated with a faster and stronger renewable increase in Switzerland.