Advanced diesel technology has been standard in new off-road engines and equipment since 2014, achieving near zero emissions.

Diesel has long been the predominant technology powering engines and equipment used in off-road mobile applications such as agriculture, construction, marine, mining, rail, and stationary applications for industrial and power generation. Continuous improvement in diesel engines has boosted efficiency and lowered emissions throughout the last two decades.

Since 2014, new engines that power equipment commonly found in most construction and agricultural applications achieve near-zero emissions for particulate matter and nitrogen oxides in compliance with U.S. Environmental Protection Agency (EPA) emissions standards. Similar requirements were effective for new engines powering marine vessels and locomotives since 2015. 

EPA emissions standards apply to new and remanufactured engines. They do not apply to existing engines.

New engines manufactured since 2015 (“Tier 4 compliant”) significantly reduce emissions of particulate matter (PM) and oxides of nitrogen (NOx) to near zero levels. Relative to previous emissions standards, this generation of advanced diesel technology reduces emissions by more than 95% for most agricultural and construction equipment and just over 86% for larger applications like locomotives and marine vessels. Emissions requirements are further determined by the horsepower ratings of the machine or equipment.

The Tier 4 generation of technology for off road engines and equipment followed a similar path to that from the emission reduction requirements for engines that power heavy-duty trucks. While engine manufacturers utilize a nearly uniform suite of advanced diesel technologies to meet the truck emission standards (particulate filers and selective catalytic reduction), a wider variety of approaches are evident in off-road applications given the many variations in engine sizes, horsepower ratings, and equipment use characteristics.

In addition to achieving near-zero emissions, manufacturers at the same time are boosting productivity of the equipment and reducing fuel consumption through a variety of approaches. These include advanced engine combustion designs, hybridization, advanced energy storage capabilities, and idle reduction technologies.

The use of smart technologies such as remote control, autonomous vehicles, global positioning systems, and telematics connect machines together and integrate to the demands of the job site. These smart and connected systems optimize equipment utilization, reduce idle time and conserve fuel, thereby reducing greenhouse gas emissions while boosting productivity and reducing time and project costs.