Final Report: An Inexpensive Hand-Held Monitor for Measuring Fugitive Methane EmissionsEPA Contract Number: EPD17035
Title: An Inexpensive Hand-Held Monitor for Measuring Fugitive Methane Emissions
Investigators: Kimble, Michael C.
Small Business: Reactive Innovations, LLC
EPA Contact: Manager, SBIR Program
Project Period: September 1, 2017 through February 28, 2018
Project Amount: $100,000
RFA: Small Business Innovation Research (SBIR) - Phase I (2017) RFA Text | Recipients Lists
Research Category: Small Business Innovation Research (SBIR) , SBIR - Air and Climate
Methane is the second most prevalent greenhouse gas emitted after carbon dioxide, however, on a pound-to-pound comparison methane has a 25 times greater impact on climate change than carbon dioxide over a 100-year period. Accordingly, the 2014 Climate Action Plan directed agencies including the USDA, DOE, and EPA to reduce methane emissions. A significant effort in the Climate Action Plan is to develop improved measurement methods that focus on the specific source or activity causing the emissions, not inferred from atmospheric methane concentrations. This is important to characterize emission sources with precision which is critical for designing mitigation strategies.
Toward this need, Reactive Innovations conducted a Phase I SBIR project for the Environmental Protection Agency to develop a hand-held methane sensor that can be used to measure fugitive methane emissions in support of the Climate Action Plan. Specifications for the sensor have been defined by cooperating government agencies that include a methane detection concentration in air of 2-250 ppm plus or minus 2 ppm, real time concentration determination, calibration capabilities, a continuous readout, electronic transmission of stored data, and a cost less than $50.
Toward detecting and measuring methane in air, a new sensing approach was developed based on specific electrochemical response pattern recognition technology. With this platform, an ion- exchange membrane serves as a solid-state electrolyte between two electrodes designed specifically for assessing methane without interferents affecting the response. It was demonstrated that these electrodes could be operated in varying electrochemical interrogation modes including cyclic voltammetry to give a telltale signal indicative of the methane concentration. This membrane transducer is compact on the order of 5 to 25 cm2 in size and has a very low material cost of approximately $16 based on present-day low-volume procurement.
A cost assessment was made of packaging this membrane transducer into a self-contained sensor package that contains electronic hardware we have produced for autonomous sensor nodes. This hardware includes the electronics circuit board to drive the electrochemical interrogation process, a wireless communication board to wirelessly transmit the sensor data to other sensor nodes or to a central receiver, two AA batteries, and a weatherproof housing. With these components including the membrane transducer, this sensor node has a present-day Phase I cost of $53.
Continued development of the membrane transducer and electronics will ensure this sensor product meets the government goal of $50 while improvements continue with the electrochemical response measures for fugitive methane emissions.
With this new methane sensing approach, we successfully developed and demonstrated for the first time a new specific electrochemical response pattern recognition technology that targeted methane. This was demonstrated with a 200 ppm methane in air concentration showing the technical feasibility of the new sensing method. Toward economic viability, this sensing technology has a present day cost of $53 including the membrane transducer, electronics, batteries, and a housing, a value close to the $50 cost target. Further development of this technology will enable both hand-held monitors and autonomous sensor nodes for fenceline monitoring of sites with fugitive methane emissions.