EFFICIENT EMISSIONS SOLUTION
The first Tier 1 emissions standards where set in 1996 by the Environmental Protection Agency (EPA) in the United States, (CEPA) in Canada and by the (EU) in Europe. The primary focus was the reduction of Nitrogen Oxide (NOx) and Particulate Matter (PM). Aggressive standards have continued to be implemented since this time to reduce the amount of these pollutants being released into the atmosphere. The latest emissions standards are known as Tier 4, which have been implemented in a two prong approach, Tier 4A and Tier 4B, which started in 2014. Since the introduction of these stringent regulations in 1996, Nitrogen Oxide (NOx) and Particulate Matter (PM) have been reduced by 95%.
Traditionally there have been two different engine solutions for meeting the Tier 4 regulations, SCR, or Selective Catalytic Reduction, and CEGR, or Cooled Exhaust Gas Recirculation. The fundamental difference between SCR and CEGR is that SCR controls the PM internally by allowing the engine to run as efficiently as possible, then converting the NOx outside the engine to nitrogen and water by treating it with urea (or DEF). CEGR, on the other hand, reduces NOx inside the engine by reducing combustion temperatures. However, this reduction produces more PM, which must then be filtered out externally by a particulate filter.
SCR is an after-treatment system that is separate from the main engine function and does not compromise horsepower or torque. It does not interfere with engine performance, but actually improves it. Exhaust gas is NOT recirculated
through the engine and it does not require regeneration of particulate filters, which can compromise efficiency. SCR technology is the best approach for larger, higher-horsepower agricultural power products, especially when considering the importance of fuel efficiency and maintenance costs.