This handbook is divided into two main sections and an appendix. The electrical engineering section covers equipment operating at voltages up to and above 1 kV, including circuit breakers, transformers, capacitors, and cables, as well as lighting systems. The thermal engineering section focuses on power and heat-mechanical equipment, providing information on energy fuels, industrial boiler installations, steam and hot water boilers, pumping machinery (such as pumps, fans, and compressors), and heat exchangers. It also includes a chapter on autonomous energy supply sources for industrial facilities. The appendix addresses energy auditing procedures and lists equipment parameters necessary for conducting such audits. The book is tailored to meet the needs of professionals involved in the operation of electrical and thermal systems, devices, and equipment. It is particularly useful for energy specialists in industrial and agricultural enterprises, as well as engineers, technicians, and maintenance personnel responsible for energy supply systems. Additionally, it may serve as a valuable resource for students studying energy engineering.