Prechamber Enabled Mixing Controlled Combustion of Natural Gas for Ultra-Low Methane Emissions from Lean-Burn Engines

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Milwaukee, Wisconsin
Project Term:
06/01/2022 - 05/31/2025

Technology Description:

Marquette University will enable an innovative combustion technology for lean-burn (high air-fuel ratio) natural gas engines to potentially reduce the amount of methane slip—or methane in the inlet fuel stream that escapes to the atmosphere—to 0.25% of the inlet fuel stream. The 0.25% target would represent a 90% reduction from current levels. The proposed system aims to achieve a non-premixed, mixing-controlled combustion process with natural gas in a lean-burn engine through an actively fueled prechamber. Simulations have shown that this non-premixed combustion system yields a 10-fold reduction in methane slip compared with a conventional lean-burn natural gas engine. This system could be retrofitted to existing lean-burn engines or as a new engine technology. The proposed concept will deliver a transformational reduction in methane slip while meeting site-specific targets for criteria pollutants, reliability, and durability. It also provides a pathway to a transformational reduction in total greenhouse gas emissions as a new engine technology via significant increases in efficiency.

Potential Impact:

REMEDY addresses methane emissions from domestic oil, gas, and coal value chains, accounting for 78% of U.S. primary energy.


REMEDY systems will reduce the environmental footprint from the production and use of domestic resources.


A key REMEDY process performance metric is to reduce net greenhouse gas emissions > 87% on a life cycle basis. This metric ensures proposed solutions provide a holistic environmental benefit. If successful, REMEDY processes have the potential to reduce U.S. methane emissions by at least 60 million tons of CO2e (carbon dioxide equivalents) per year.


REMEDY goals call for 99.5% methane reduction while meeting a levelized cost less than $40/ton of CO2e.


ARPA-E Program Director:
Dr. Jack Lewnard
Project Contact:
Dr. Adam Dempsey
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