Achates Power announced that its 10.6 L opposed-piston heavy-duty powertrain has achieved NOx emission levels that would satisfy the 2027 low NOx FTP emission limit by the California Air Resources Board (CARB).

The most recent test of the engine, including aftertreatment, measured 0.02 g/bhp-hr of NOx over the FTP test cycle, demonstrating the capability of the engine to be certified under CARB low NOx regulation, according to Achates. However, the opposed piston engine would still need to demonstrate compliance with CARB low NOx limits over the low load cycle (LLC) and other requirements of the CARB low NOx regulation such as the extended emission durability periods.

Additionally, the 10.6 L engine emitted 422 g/bhp-hr CO2 over the SET cycle, which is below both the current US EPA standard of 460 g/bhp-hr and the 2027 value of 432 g/bhp-hr.

Achates 3-cylinder 10.6 L opposed piston engine

These results were achieved with a conventional diesel aftertreatment system utilizing a single SCR catalyst, which makes the powertrain system less complex and less expensive compared to the dual dosing SCR systems envisioned for meeting the 0.02 g/bhp-hr NOx limit on conventional diesel engines.

The 10.6 L opposed-piston engine was developed as part of a demonstration project funded by CARB and several California air districts. Engine and aftertreatment system development and performance assessments were conducted at the Achates Power facility in San Diego and the Aramco Research Center in Detroit.

Originally posted on DieselNet (December 18, 2020) (View original article on DieselNet)

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