The Second Coming of the Opposed-Piston Engine: A Look at Achates Power
In the rapidly evolving landscape of sustainable transportation, an architecture from the 1930s is making an unexpected and powerful comeback. Achates Power , a San Diego-based engineering firm founded in 2004, has spent over two decades refining the , transforming a historic design into what they claim is the cleanest and most efficient internal combustion engine (ICE) demonstrated to date. A Radical Departure from Convention
There are no valves, camshafts, or rocker arms.
Its inherently low NOx emissions allow for smaller, less expensive exhaust systems. Efficiency by the Numbers
Unlike a standard engine, the Achates design features two pistons per cylinder moving toward each other, meeting in the center for combustion. This "head-to-head" arrangement eliminates several of the most complex and failure-prone parts of a traditional engine, including:
The primary draw of Achates technology is a "step-function" improvement in efficiency. By combining a two-stroke cycle with the opposed-piston architecture, the engine achieves:
By removing the head, the engine drastically reduces heat loss.