Achates’ demonstrates up to 20% efficiency improvement v. today’s engines while meeting 2027 ultra-low NOx standards with today’s aftertreatment

LAS VEGAS–(BUSINESS WIRE)–Achates Power, Inc. (API) showcased at ACT Expo what has been demonstrated as the cleanest and most efficient internal combustion engine (ICE) architecture to date. Demonstrations have proven ability to satisfy regulatory requirements without detriment to the fleets or economy.

In pursuit of clean technology, it’s critical to place priority on the fleets and drivers. Technology-forcing regulations with uncertainty on infrastructure, cost, and capability to ‘do the job’ make it difficult to navigate this energy transition,” said Dave Crompton, CEO of API.

For the first time, an ICE architecture has been simultaneously proven to reduce NOx, beat the most stringent regulations proposed with margin to spare, and improve real world fuel economy by as much as 20%, while demonstrating extended life compliance.”

API demonstrated the opposed-piston (OP) architecture is capable of using today’s aftertreatment systems to meet tomorrow’s ultra-low NOx emissions standards with robust compliance through the 800,000 mile useful life requirements. Low-load, idle, and off-cycle emissions capability positions this to be the best combustion technology in the industry.

Stringent emissions regulations in commercial trucking are to a point where aftertreatment systems’ cost and complexity may drive truck costs higher, reliability lower, and penalize fuel economy. In a joint demonstration with CALSTART and Walmart, an API 10.6 liter 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. 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.

In February at Argonne National Laboratory, the Department of Energy began testing an API engine utilizing hydrogen combustion with compression ignition. The simplicity of this design enables an easier transition to hydrogen combustion over 4-stroke concepts.

In joint testing with renewable diesel producer Neste, the already proven 10% greenhouse gas emissions (GHG) reduction of the OP engine was amplified when using R99. Testing resulted in 4-5% GHG emissions reduction compared to fossil diesel across all test cycles – the lowest GHG level API measured to-date.

Benefits of the API engines include lower heat rejection, higher power density, and fewer moving parts for better reliability and increased fuel efficiency. Every stroke is a power stroke, providing optimal thermal efficiency. This matters to fleets for 2027 and beyond emissions regulations where thermal management impacts aftertreatment cost, simplicity and functionality.

API technology is obtainable without the use of exotic materials, non-conventional manufacturing, or complex aftertreatment systems – making it a ‘now’ solution for the fleets.

API has demonstrated that its technology can be put into practical use without the added complexity, cost and reliability concerns associated with stretching conventional engines and emission systems to meet the future low NOx and CO2 limits, and without the need for a fleet to redesign routes around shorter-range vehicles and sparse refueling/recharging infrastructure,” said Dr. John Wall, Board of Directors, API and former Cummins CTO. “For fleets that ultimately want to reach zero-net-carbon emissions, including renewable diesel and hydrogen, the Achates technology is a good match.”

This architecture can be manufactured through sustainable assembly practices and with approximately 300 fewer parts compared to today’s 4-stroke engines. Materials can be procured through today’s supply chain efficiently supporting the manufacturing of this engine architecture without sourcing disruptions and constraints.

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Steve Sanders