Pinnacle
Illustration of a three-cylinder configuration of the Pinnacle opposed-piston engine. Click to enlarge.

Startup Pinnacle Engines unveiled plans to commercialize a new, more efficient combustion engine by 2013. The company says the new engine design enables significant reductions in fuel consumption and greenhouse gas emissions without increasing vehicle cost. Pinnacle has raised $13.5 million in venture funding from NEA, Bessemer Venture Partners and Infield Capital.

The Pinnacle engine is based on a four-stroke, spark-ignited (SI), opposed-piston, sleeve-valve architecture. Pinnacle says the engine achieves 30-50% better fuel economy in various drive cycle comparisons without the large cost penalty that can be associated with significant fuel economy improvement. The performance of the Pinnacle Engines design has been independently verified by FEV, Inc., a Pinnacle Engines development partner.

Engines that can deliver significant efficiencies within 5 – 10 years are critical as the global demand for vehicles places a strain on both natural resources and the environment. We believe Pinnacle Engines is in a unique position to have a major impact in that timeframe, by delivering exceptional efficiency gains at the lowest possible cost.

—Rohini Chakravarthy, Pinnacle Board member and a Partner at NEA

The core of Pinnacle’s technology resides in its engine architecture and the new “Cleeves Cycle”. (James Montague (Monty) Cleeves is the Founder, President, and CTO of Pinnacle.) The Cleeves Cycle operates on the Otto cycle (constant volume combustion) or Diesel cycle (constant pressure combustion) depending on operating conditions. Additional efficiency improvements will be realized through incorporation of variable valve timing, direct injection, turbocharging, and Pinnacle’s own low-cost variable compression ratio mechanism.

The result, says Pinnacle, is a more fuel efficient and scalable engine design, and one that is compatible with most fuels including gasoline, diesel, natural gas, propane and their biofuel replacements.

The company is in the process of commercializing its technology through a joint development and licensing agreement with an Asian vehicle OEM. Production is slated to commence in Q1 2013. Further developments, including plans for expansion into the global automotive market, will be revealed later this year.


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