Volume 2 of the book was the result of the need to show the evolution of the Intelligent Electronic Devices (IEDs) not only as protection relays applied for generation based on new renewable energies, but also as information centers, necessary for a correct operation and optimization of the use of these new energies. Aspects such as wind and solar power systems and their integration into conventional networks have been addressed. It has also included the description of protection systems for HVDCs; High-Speed Train Networks, definition and analysis of some network protections such as System Integrity Protection Schemes (SIPS), and an integral vision of the Grid Modernization as part of the evolution of the Electrical System.