Posters

Abstract

Recent updates in the legal Spanish framework related to hybrid power plants and their administrative validation process have motivated renewable project developers to consider hybridization. The plants that can be suitable for hybridization are commonly PV-Wind plants, which are specially interesting in Spain due to the complementarity of wind and solar resource, not only in a daily distribution, but also along the year. The newly passed law indicates that, in order to consider a power plant as hybrid, the installed power of the primary energy source needs to make up at least 40% of the total installed power. To illustrate this, a 40 MW renewable energy plant could be hybridized with a maximum of 60 MW of a second renewable energy source. However, assuming that the granted grid connection energy is the same as the installed power of the primary energy source, the installed power of the secondary energy source will need to be optimized according to the curtailment losses and the complementarity of both energy sources in the location. The starting point for the presented case would be an already operating PV plant located in the Spanish region of Castilla-La Mancha, that will be considered as the primary energy source of the site, with a rated power of 100 MW. The proposed calculation procedure will optimize a wind farm as the secondary energy production source and determine the maximum number of wind turbine generators that will be profitable for the hybrid plant, before the curtailment losses become too significant and penalize its efficiency. To accomplish that objective, a ‘type wind farm' needs to be previously designed, which is representative of the site, and used to conduct energy production assessment. Afterwards, the results will be expressed in 0.1 MW increments, and more than 1000 iterations will be run in order to identify the precise effect of each additional MW in the total efficiency. When the optimization procedure results are analyzed, it can be concluded that installing all the maximum permitted power for the secondary energy sourced will never be efficient, since the curtailment losses that appear could represent as much as 50% of the energy produced. In order to diminish those losses, the installed power must be reduced too, until a balance point is reached. That point has been proven to be established at, approximately, 66% of the power permitted to hybridize. However, when impact of each MW is analyzed, it can be seen that the optimal point is reduced to 40% of the power permitted to install. As a conclusion, this study can precisely describe how the last installed wind turbine generator affects to the hybrid plant efficiency and determine the number of turbines that would maximize the profitability of the entire project.