March 2022 – Energy Scouts reduce process wastewater with filter system at Bosch Slovakia

Robert Bosch Production Slovakia s.r.o., a company with around 170 employees and headquarters in Bernolákovo, is part of the Mobility Solutions division of the BOSCH Group. The plant renews starters and alternators for the Bosch Group worldwide. The company’s internal “eXchange program” helps reduce the environmental impact of driving by reusing components. This is because remanufactured starters and alternators require up to 88% fewer new components and generate 53% fewer CO2 emissions compared to manufacturing new products.

An important part of the remanufacturing process is the intensive cleaning of the components in specialized machines. The process produces about 1,500 liters of process wastewater per week at the current throughput rate and if all technical criteria are met. This is considered hazardous waste and must be treated in accordance with the relevant legislation, which entails a considerable financial effort in addition to the environmental impact.

A new filtration process is used

As part of Young Energy Europe, Energy Scouts Marek Palenčár and Adam Kabát studied options for reducing the amount of wastewater generated in the company in   their practical project. Their proposed solution is the integration of a new filtration process in the cleaning process, which reduces the amount of wastewater by 17%. With an optimal frequency of use, the need to change the wash water in the tanks can be reduced by 50%.

Practically, they use a mobile filtration unit to get the major impurities out of the wash water. Energy Scouts Marek Palenčár and Adam Kabát started in early 2022 with several weekly test operations and a borrowed OTC 350 filtration unit. The goal is to determine an optimal schedule of water filtration based on the tests performed. The water filtration in the tanks of the washing plant can take place without interrupting its operation. The filter unit must be mobile so it can be moved between the washing units.

Electricity, CO2 emissions and cleaning agents reduced – costs permanently lowered

As a result of the longer service life of the so-called gray water, the Energy Scouts also reduce the consumption of chemical cleaning agents by 20%. As less water has to be treated, the company achieves a reduction in electricity consumption of almost 6 MWh per year and at the same time an annual reduction in greenhouse gas emissions of 1.14 tons of CO2. The one-time investment cost of €18,060 will pay back after less than seven months.

The Energy Scouts Marek Palenčár and Adam Kabát impressed the expert jury at the Slovakian Best Energy Scout Awards 2021 with their detailed and thought-through concept and won second place overall.

 Process Optimization


Consumption of Water

  • Industry sector: automotive supplier
  • Energy source: electrical energy
  • Energy saving potential: 5.95 MWh/a
  • CO2 saving potential: 1.14 tons CO2/a
  • Potential cost reduction: 34,284 €/a
  • Investment cost: 18,060 €
  • Payback period: 0.75 years
  • Company:
    Robert Bosch Production Slovakia, s.r.o.
    Gaštanová Alej 7
    900 27 Bernolákovo
Project Manager and Technical Advisor Tomáš Szabo with Energy Scouts Adam Kabát and Marek Palenčár preparing for the test runs (©Bosch Slovakia s.r.o)
Energy Scout Marek Palenčár with Tomáš Szabo connecting the mobile filtration unit. (©Bosch Slovakia s.r.o)
Turning old into new - views of the opened ET100 unit with cleaned components. (©Bosch Slovakia s.r.o)
Proud Energy Scouts - Human Resources Manager Peter Vitoslavsky (center) congratulated for the second overall place to Energy Scouts Adam Kabát and Marek Palenčár. (©Bosch Slovakia s.r.o)