Strategic generation investment using a stochastic rolling-horizon MPEC approach

Investments in power generation assets are multi-year projects with high costs and multi-decade lifetimes. Since market circumstances can significantly change over time, investments into such assets are risky and require structured decision-support systems. Investment decisions and dispatch in electricity spot markets are connected, thus requiring anticipation of expected market outcomes. This strategic situation can be described as a bilevel optimization problem. At the upper level, an investor decides on investments while anticipating the market results. At the lower level, a market operator maximizes welfare given consumer demand and installed generation assets as well as producer price bids. In this paper, we formulate this problem as a mathematical program with equilibrium constraints (MPEC). We consider this model to include a dynamic, rolling-horizon optimization. This structure splits the investment process into multiple stages, allowing the modification of wait-and-see decisions. This is a realistic representation of actors making their decision under imperfect information and has the advantage of allowing the players to adjust their data in between rolls. This more closely models real-world decision-making and allows for learning and other feedback in between rolls. The rolling-horizon formulation also has the beneficial byproduct of computational advantage over a fixed-horizon stochastic optimization formulation since smaller problems are solved and we provide supporting numerical results to this point.

On the Impact of Wind Feed-in and Interconnections on Electricity Price in Germany

In this paper, we explore carry out an empirical analysis for Germany, as a country with high penetration of wind energy, to investigate the interaction between the well-known merit-order effect, i.e., falling spot price levels as well as highly fluctuating spot prices and the European electricity grids inteconnections,i.e., market coupling.Our main empirical findings suggest that wind power in-feed decreases electricity spot price level but increases spot prices volatility. Furthermore, the relationship between wind power and spot electricity prices can be strongly impacted by European electricity grids interconnection which behaves like a safety valve lowering volatility and limiting the price decrease. Therefore, the impacts of wind generated electricity on electricity spot markets areless clearly pronounced in interconnected systems