February 2024 – By sealing micro leaks in a compressed air system, two Serbian Energy Scouts achieve amortization time of only 47 days

For more than 20 years Flender d.o.o. produces wind generators and stator segments of wind generators in Subotica, in the uttermost north of Serbia. It was founded in 2003 as Loher Elektro Subotica and for 15 years, it belonged to the Siemens group. Today, Flender d.o.o. Subotica is part of the Winergy group within the company Flender with around 1,300 employees.

Energy Scouts Glišić Luka and Vučković Todor were looking for a solution to reduce the energy costs, and with electricity being the most expensive energy source, they aimed for two electricity saving projects.

Scouting for project ideas, they addressed “classic” categories in the fields of energy efficiency, like lighting and compressed air systems. The results were impressive: their planned measures reduce electricity costs by as much as 50%!

First, they replaced the metal halide lighting with 1,041 new LED lighting systems. Thus, they saved 1,690 MWh and 1,528 tons of related CO2 emissions per year. The investment of 80.000 € paid off after only 161 days.

Secondly, the Energy Scouts detected and repaired micro leaks, most of them on the installation and connections off the compressed air system. They detected the leaks with an ultrasonic detector (SDT 200), using two a parabolic and flexible sensor. After the test was completed, 72 high-level leaks had been located, which led to an increased air consumption of 841.853 m³ per year. Each saved cubic meter of compressed air relates to high savings on electricity cost for the compressors.

By replacing the broken seals and parts they invested roughly 2,000 € once but reduced the electricity costs by roughly 15,000 € per year. This measure returns on invest after only 1.5 months! An additional 105 MWh electricity and 95 tons of CO2 saved per year.


Compressed Air Systems

  • Industry sector: production of electric motors, generators and transformers
  • Energy source: electricity
  • Energy savings potential electricity: 1,690 MWh/year + 105 MWh/year (lighting & compressed air)
  • CO2 savings potential: 1,528 tons CO₂/year + 95 tons CO₂/year (lighting & compressed air)
  • Potential cost reduction: 14,943 €/year (compressed air)
  • Investment costs: 80,000 € + 1,920 € (lighting & compressed air)
  • Payback period: 161 days + 47 days (lighting & compressed air)
A woman and three men stand in front of a large display with Young Energy Europe branding, two of them holding up certificates
Energy Scouts Vučković and Glišić at the certificate award, surrounded by the Serbian YEE-Team Tara Jevremović and Milan Krstić (©AHK Serbien/Bogdan Bogdanović)
A man in front of the control monitor of an air compressor
Scout Vučković checking the compressors parameters. (©Flender)
Two men standing in an engine room
Energy Scouts Vučković and Glišić replacing the air connections of the preparatory group in the sandblasting plant. (©Flender)
A man works on a connection with hoses
Energy Scout Glišić replacing another connector with a micro leak . (©Flender)