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Verified Technologies for SmartWay and Clean Diesel

Learn About Marine Technology

Verified Marine Technologies for SmartWay and Clean Diesel

Options to save fuel and reduce emissions from marine engines include:
  • Repowering (i.e., replacing) or upgrading engines; and
  • Installing retrofit emission control technologies. 
Engine upgrades or retrofit devices can be installed on new or existing marine vessels and equipment to reduce:
  • Fuel consumption;
  • Particulate matter (PM);
  • Nitrogen oxides (NOx);
  • Hydrocarbons (HC);
  • Carbon monoxide (CO);
  • Carbon dioxide (CO2); and
  • Other air pollutants.
Besides repowering or replacing older engines with newer Tier engines, there are several retrofit devices for marine engines included in the Clean Diesel Verified Technologies List, located here:

Verification for Marine Technologies

Technologies to save fuel and reduce emissions for marine engines can be verified by EPA. Due to the unique nature and custom design of these technologies, EPA will review and approve them on a case by case basis.  

For inquiries, please contact:

Marine Shore Power Connection Systems

Shore power systems allow maritime vessels to “plug into” land-based electrical power while at dock instead of using on-board diesel engines. Shore power systems must enable a compatible vessel’s main and auxiliary engines to remain off while the vessel is at berth. Systems typically include various components such as cables, cable management systems, shore power coupler systems, distribution control systems, and power distribution.

Due to the unique nature and custom design of marine shore power connection systems, specific products and vendors are not listed. Marine shore power systems must comply with international shore power design standards (ISO/IEC/IEEE 80005-1-2012 High Voltage Shore Connection Systems or the IEC/PAS 80005-3:2014 Low Voltage Shore Connection Systems) and should be supplied with power sourced from the local utility grid.

To get a better understanding of Shore power systems EPA commissioned a report titled Shore Power Technology Assessment at U.S. Ports which reviewed the availability of shore power at ports and characterized the technical and operational aspects of shore power systems installed at U.S. ports.  A calculator tool provided with this report can be used to estimate how harmful air pollutants could be reduced at U.S. ports through the use of shore power systems; benefiting air quality, human health, the economy, and the environment.  The estimates can be used in conjunction with EPA’s Diesel Emissions Reduction Act (DERA) program to help evaluate potential shore power projects for grant applications, and for reporting emission reductions from grant projects.