Electrotechnics as a branch of science and technology with the aim of research and use of electromagnetic phenomena experienced its formation in the 19th century. There were invented the first electric machinery. The electric current started being used for illumination and as power in industry. In the 20th century electrical energy conquered the world. For the practical use of it big merit could be attributed to the teaching staff and students of Riga Polytechnic School and Riga Polytechnic Institute such as A. Teplers, E. Arnolds, M. Dolivo-Dobrovolskis etc.