Presentations

Abstract

Hybrid power plants are becoming increasingly popular as they enable the optimization of network usage by integrating additional capacity from diverse and potentially complementary technologies. Hybridization maximizes the utilization of existing infrastructure, offering various advantages such as reduced energy production costs through shared land, infrastructure, and O&M expenses, enhanced operational flexibility, and diminished investment uncertainties. The proliferation of hybrid projects is further fueled by favorable regulations in certain regions, streamlining permitting processes and fostering development. Typical wind and solar hybrid projects consist of a wind and solar plant which overall capacity overpasses the authorized grid evacuation capacity, therefore besides assessing the expected energy production of the wind and solar plants, the expected energy curtailments given the grid export limit must be calculated. The extent of curtailed energy depends significantly on the specific realization of power time series for both wind and solar technologies over time. Therefore, accurate energy production estimations for new hybrid plants demand power modelling with high time resolution, ensuring that the long-term climate variability and wind-solar correlation are well captured. In this study, DNV has evaluated various real-world hybrid projects with differing levels of accuracy for the wind energy assessments, including those based on operational data, pre-construction assessments using measurements from meteorological site mast, and pre-construction assessments based on mesoscale data. The objective is to assess and quantify uncertainties in energy curtailment estimations based on the quality of input data and different modeling approaches. DNV has analysed the differences in the estimated energy curtailment depending on the different levels of accuracy (meter data, site mast-based and mesoscale-based) of the underlying power time series used for the calculations. Additionally, energy curtailment exhibits a high temporal variability, influenced by fluctuations of wind and solar energy production and changes in the correlation patterns between the two resources. The study evaluates the differences in the energy curtailment assessment based on the duration and representativeness of the period used for power modelling, considering historical data, long-term synthesized data, and typical meteorological years. Finally, the research investigates the significance of time resolution in time series modelling, analysing the potential underestimation of the expected curtailment when using hourly instead of sub-hourly data. This comprehensive analysis contributes valuable insights for enhancing the precision and reliability of energy curtailment evaluations in wind and solar hybrid projects.