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Diesel Inventory Reduction Through Repower Technology

Working in conjunction with Michigan CAT and the U.S. Environmental Protection Agency Region 5 office, Clean Energy Coalition has upgraded approximately 21 CAT engines to help clean up Michigan’s legacy fleet to essentially Tier-1 emissions levels. This project was accomplished through the funding of emissions upgrade groups.

Older diesel engines contribute significantly to air pollution in Michigan. According to EPA emissions inventory data, off-road mobile sources contributed 17 percent of nitrogen oxide (NOx), 30 percent of volatile organic compounds (VOCs), and 30 percent of particulate matter (PM10) emissions in Michigan. As listed on EPA’s National Clean Diesel Campaign website, upgrading an older engine is an effective retrofit option for reducing these pollutants. With emissions reductions such as these, it’s no wonder the Clean Energy Mobility team tackled these aged machines.

The Clean DIRRT project had an average cost effectiveness of $1,046 per ton of pollutants. Source U.S. EPA

Program Accomplishments

During the course of five years, the Clean DIRRT project will have these quantifiable emissions reductions:

  • 56.4 tons of NOx
  • 3.2 tons of PM10
  • 10.7 tons of hydrocarbons