ETAP is described as 'is the most comprehensive enterprise solution for design, simulation, operation, control, optimization, and automation of generation, transmission, distribution, and industrial power systems'. There are more than 10 alternatives to ETAP for a variety of platforms, including Windows, Online / Web-based, Android, iPad and Self-Hosted solutions. The best alternative is Catia. It's not free, so if you're looking for a free alternative, you could try DOC or WSCAD SUITE X PLUS. Other great apps like ETAP are See Electrical (Paid), EPLAN Electric P8 (Paid), PowerFactory (Paid) and SolidWorks Electrical (Paid).
CATIA (Computer Aided Three-dimensional Interactive Application) (in English usually pronounced /k?'ti?/) is a multi-platform CAD/CAM/CAE commercial software suite developed by the French company Dassault Systèmes.
DOC is a software dedicated to the design and calculation of single-line diagrams of electrical systems in low and medium voltage, allowing the user to choose switching devices and security, and for verification and coordination of protective devices.
SOLIDWORKS Electrical schematic design capabilities simplify development of embedded electrical systems for machines and other applications, with single-line and multi-line schematic tools for planning your electrical systems.