5220303 Hydropower
5220308 Renewable energy sources
5220309 Heat engineering – heat, air conditioning, ventilation and refrigeration
5220401 Thermal power engineering
5220403 Hydropower
5220408 Renewable energy sources
5220409 Heat engineering
5220501 Operation of steam and water heating facilities
5230101 Radio and television equipment
5230102 Telecommunication systems
5230103 Radar, radio navigation and hydroacoustic systems
