Selective Catalytic Reduction (SCR)

The basic engine design does not need any changes for applying SCR.

Fuel-water emulsion (FWE)

The technology can be applied to all vessels and no retrofit is required. Tests by German inspection authority ‘TÜV Nord’ shows a potential reduction impact of particulate matter by approximately 80% and NOx emission by approximately 25% (on a EURO III engine). To achieve more ambitious emission standards, FWE can be combined with an SCR system to further reduce NOx emission. FWE reduces fuel consumption by approximately 2%.

Some stakeholders state that engine corrosion cannot be ruled out, extensive maintenance would be required and defects of fuel injection systems are possible. However, FWE is regarded as a promising technology by German officials. Beginning in 2013, this technology is considered in the German support programme for the installation of engines and technologies to reduce emission of inland navigation vessels.

Diesel particulate filters (DPF)

Diesel particulate filters have become the most effective technology for the control of diesel particulate emissions -including particle mass and numbers- with high efficiencies.


  • Catalyst (SCR) + Filter (DPF)
  • Fuel Water Emulsion (FWE)
  • Fuel Water Emulsion (FWE) + Catalyst (SCR)
  • Catalyst (SCR)

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