The 50th magazine edition presents advanced solutions for hotel lighting cost optimization. The article discusses some types of control systems and automation of lighting, which provide significant energy savings. The second theme in the section on lighting focuses on LED emergency lighting and evacuation. The article "Automatic control of building installations" describe the functionality of current systems for building automation and trends in their development. Rubric "HVAC" presents a technical solution for energy efficiency improvement of HVAC systems, using frequency converters for speed control of pumps and fans. The types of automated fire extinguisher systems are subject to the "Security Systems" section. Other interesting topics in the issue are "Electrical solutions for office buildings,"Shut-off valves for water systems” and others.