On display at ACT Expo in Las Vegas this week is what Achates Power, Inc. (API) described as the cleanest and most efficient internal combustion engine (ICE) architecture demonstrated to date.
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API said it has demonstrated the opposed-piston (OP) architecture is capable of using today’s aftertreatment systems to meet future ultra-low NOx emissions standards with compliance through the 800,000-mile useful life requirements. It also offers low-load, idle and off-cycle emissions capability.
In a joint demonstration with CALSTART and Walmart, an API 10.6 L engine was retrofitted into a production Class 8 truck to meet the proposed 2027 ultra-low NOx emissions standard and with an off-the-shelf current production one-box aftertreatment system, Achates noted. The company reported testing in California achieved up to 10.8 mpg on a 389-mile delivery route averaging 10% better fuel economy than baseline, with the advantage increasing to 22% on some routes.