A. Gkolemis, Stochastic investigation and simulation of wind speed - Application in management of wind works, Diploma thesis, Department of Water Resources and Environmental Engineering – National Technical University of Athens, Athens, February 2019.
With the progress of technology and the increasingly exploitation of the fossil fuels, there is an urgent need to turn humanity into renewable energy sources. Since the beginning of the 21st century, the scientific community has made huge leaps to exploit all renewable energy sources. One of the most widely known and exploitable is the wind power, which is one of the most important forms in which the human factor had relied on in the past, and is going to rely on in the future. The performance prediction of these systems is based on hourly data because these are usually the only ones available. The aim of this work is to investigate the stochastic nature and time evolution of wind speed in an hourly step, with the ultimate goal of creating a stochastic model of simulation and reproduction of the latter, carrying out the analysis on a global scale. Several distributions were checked for the wind description, with the best adjustment being achieved with the PBF distribution (also known as Burr), according to statistical analysis results. Wind is a process that is simulated by a stochastic model, in which we use deterministic functions. In order to simulate properly, deterministic functions, namely hourly and monthly periodicities, are adapted using some dual periodicity models. Subsequently, a pseudo-cyclostationary, long-term persistence model is created to replicate the wind speed.The model is checked and satisfies the maintenance of the distribution of the four central moments (mean value, standard deviation, asymmetry and kurtosis), as well as the Hurst parameter that expresses (long-term) persistence and correlation. Last but not least, is the examination of the financial management of a wind power plant. The difference in the forecast of the money that the wind power plant will produce for each one of the analyzed distributions, as well as the economic analysis in the investment of a wind power plant with and without its replacement at the end of its lifespan, is studied. All costs are presented in detail and cash flow tables based on energy efficiency are compiled in order to calculate the net present value indicator.