Capacity investment on electricity markets under supply and demand uncertainty: an overview

In the last decades, the weight of renewable energies sources (RES) in the electricity generation mix of most European countries has considerably increased. The implementation of these policies has been relying on different supporting schemes such as: the existence of a price premium for RES (feed-in tariffs); the assignment of priority access to renewable sources over conventional sources when entering the electricity network; and subsidizing investments in RE. While these incentives have certainly played a very important role in launching renewable energy production in Europe, more recently, both scholars and practitioners are claiming that RE generation should now be exposed to market incentives in order to promote economic efficiency. However, the inclusion of RE in the market may significantly affect equilibrium outcomes arising in electricity wholesale markets. Recent empirical studies, e.g. Puller (2007), point that the inclusion of RES in the market reduces average electricity prices at the cost of increasing price volatility (merit of order effect). Such outcomes can be explained by the intermittent nature of RES together with the asymmetry on generation marginal costs between RES and non-renewable energy sources (with the former being quite low for most of the available RES). However, the inclusion of RES in the wholesale electricity market may also yield strategic effects, as firms may strategically manipulate renewable energy production in order to have greater market power. In this paper, we provide an overview of the investment challenges following the introduction of market-based mechanisms for renewable production. The next step of this research project will be the development of a theoretical model, building on Milstein and Tishler (2011) in order to address the regulatory challenges related to capacity investment in a market with uncertain demand in which two firms offer two different electricity generation technologies, respectively using renewable and non-renewable energy sources. The renewable energy production is assumed to have an intermittent nature.