Highly-Efficient Opposed Piston Engine For Hybrid Vehicles (“HOPE-Hybrid”)

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OPEN 2018
San Diego, California
Project Term:
01/28/2019 - 12/27/2020

Technology Description:

Achates Power will develop an opposed-piston engine suitable for hybrid electric vehicle applications. The team will use a unique gasoline compression ignition design that minimizes energy losses (e.g., heat transfer) typical in conventional internal combustion engines. A motor-generator integrated on each engine crankshaft will provide independent control to each piston and eliminate all torque transmitted across the crankshaft connection, thus reducing engine size, mass, cost, friction, and noise. Engine efficiency improvement is expected through this real-time control of the combustion process. The proposed technology has the potential to offer manufacturers a full-range of cost-effective solutions to improve vehicle efficiency and reduce CO2 emissions.A highly efficient hybrid opposed-piston engine can be easily integrated in the existing fueling infrastructure and offers the power and convenience that U.S. consumers demand.

Potential Impact:

Achates Power will design and demonstrate a more efficient electrified internal combustion engine that will significantly reduce petroleum consumption and carbon dioxide emissions in the United States.


The new engine design will have better fuel economy, which could reduce the demand for imported oil.


This technology has the potential to reduce carbon dioxide (CO2), nitrogen oxides, and particulate matter emissions from vehicles, helping to improve air quality.


This team’s engine design could be extremely cost effective and allow for greater vehicle fuel efficiency at a competitive cost.


ARPA-E Program Director:
Dr. David Tew
Project Contact:
Mr. Fabien Redon
Press and General Inquiries Email:
Project Contact Email:

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