The Internal Combustion Revolution – Part 3 The Opposed Piston Opposed Cylinder (OPOC) Engine

This is one of the most popular of the up-and-coming alternative engine designs. A couple of major players in this design are EcoMotors and Navistar. While the appearances of this design are similar to the design of a boxer style “flat” engine, the design has more similarities to the 2 stroke engines used in small power equipment and motorcycles. The main difference in this design lies in the fact that each cylinder contains not one but two pistons moving in opposite directions. The fact that the design harnesses much of the force lost buy inefficiencies in the design of the Otto Cycle engine makes this a very smart and viable design. This engine architecture is on the cutting edge of technology using electronically controlled turbo chargers, and cutting edge design to achieve some pretty impressive results. EcoMotors lists a long list of benefits of their patented design including: lower weight, smaller size, an inherent balanced design, improved emissions, simplicity of design, lower production costs and perhaps most importantly improved fuel economy.The improvements in design improve the engine’s efficiency to approximately 40-50% which is impressive when you compare it to the 24% efficiency of a gas Otto cycle engine and the 33% of a well designed turbo diesel engine.

The fact that Navistar and EcoMotors have joined forces on this innovation leads many to believe that this could be one of the front running designs that makes its way into commercial and automotive use. One thing is for sure, it sure looks and sounds like a promising innovation. Time will tell….

For more information on the OPOC design EcoMotors and their joint venture with Navistar, follow the links below:

Press Release

Engine Design

How It Works — Video