This document discusses optimization techniques for sizing hybrid photovoltaic (PV) and wind energy systems. It describes three common sizing methods - yearly average, worst month, and loss of power supply probability. It also covers optimization techniques like graphical construction, probabilistic, iterative, and artificial intelligence methods. These techniques are used to simulate different system configurations and minimize total cost while maintaining reliability. The document concludes that hybrid systems can significantly reduce life cycle costs compared to standalone systems, while providing a more reliable power supply through combining energy sources.