Quantifying the effect of renewable generation on day-ahead electricity market prices: The Spanish case

The penetration of renewable generation has grown since the electricity sector has been deregulated. To account for that, this paper proposes a methodology to estimate the downward effect of renewable generation participation upon the day-ahead electricity market prices, since such an effect is quite intuitive observing the merit order of the generating units. The European Electricity Market Matching Algorithm (EMMA) is currently based on Euphemia (Price Coupling of Regions), though there are several differences among countries across Europe. The new algorithm proposed uses market orders, which include aggregate hourly orders such as aggregate supply and demand curves. These orders are simple orders and the marginal price is affected by complex orders, especially by the minimum income condition (MIC) used in the Iberian Electricity Market and considered in our proposed algorithm. A case study of the Spanish day-ahead electricity market is evaluated for 2015, for which a daily generation sample is composed of 16 days in 2015. The sample is created following the characteristics of thermal production, renewable production and inframarginal production. The conclusions are drawn comparing the simulations of the real marginal prices and the new marginal prices after incorporating renewable generation participation into the aggregate demand curve at the maximum price. (c) 2020 Elsevier B.V. All rights reserved.