The REMEDY for Methane Conversion

Q&A with REMEDY Program Director Dr. Jack Lewnard

ARPA-E's REMEDY (Reducing Emissions of Methane Every Day of the Year) program is a three-year, $35 million research effort aimed at reducing methane emissions from three specific point sources from the coal, oil, and gas sector. These three sources are responsible for 10% of anthropogenic methane emissions. REMEDY seeks technical solutions that can achieve 99.5% methane conversion and commercial scalability. If successful, REMEDY systems could dramatically reduce U.S. greenhouse gas (GHG) emissions at low cost.

ARPA-E Program Director Dr. Jack Lewnard leads the REMEDY program and focuses specifically on methane production, distribution, and use. We recently sat down with Dr. Lewnard to discuss the REMEDY program and his vision for the future.

What drove you to create the REMEDY program?

There was a consensus within ARPA-E that there are greenhouse gases beyond carbon dioxide (CO2) that represent a critical “white space,” or a problem in need of more attention. These non-CO2 gases account for more than 10% of all GHG emissions in the U.S. For example, my colleague Dr. Isik Kizilyalli put together an Exploratory Topic on reducing sulfur hexafluoride emissions, while the REMEDY program was designed specifically to explore approaches to reduce anthropogenic methane emissions.

Why is ARPA-E interested in methane emission reduction, and how does REMEDY fit in? 

Energy-related emissions are well within our scope at ARPA-E, and methane is a powerful greenhouse gas with significant emissions. Several years ago, ARPA-E launched the MONITOR program to address methane leak detection, which resulted in dramatic improvements in that technology space. With those technologies now available, our focus shifted to REMEDY and the task of methane emission reduction.

There is a long history of public-private methane reduction initiatives, including EPA’s CMOP (methane emissions from coal mining), Natural Gas Star (methane emissions from oil and gas), and industry efforts such as OGCI (oil and gas consortium addressing methane and other GHG emissions). These efforts focus on best practices and improvements to existing technologies, but ARPA-E takes a different approach.

ARPA-E questions if there are new, potentially disruptive solutions that could rapidly and dramatically change the technology landscape. These ideas are perceived as too risky for the private sector, but ARPA-E was created precisely to explore these types of risky, disruptive technologies that could have a big impact.

What makes methane emission reduction so difficult?

The challenges stem from the methane molecule itself. Methane only burns at a concentration greater than 4%, and it requires a high-energy ignition source or must be heated to a high temperature to get it to burn. Further, since methane is so stable, it is difficult to get it to react and convert. REMEDY targets emissions that are diluted at a concentration below 4% and/or in gas streams that are relatively cold, parameters that make it difficult to convert methane.

What are the technical topics of interest and how do they address the critical need for this new program? 

REMEDY is focused on three specific sources that are difficult to abate. The first source is coal mine ventilation air methane exhausted from approximately 250 operating underground mines. It is critical to ensure methane concentrations are kept low in the mines to prevent explosions, fires, and fatalities. The only practical option is to force air through the mine and exhaust the methane into the atmosphere. For this practice to be safe, the methane needs to be too dilute to ignite. ARPA-E needs innovative solutions for ways to destroy the methane after it leaves the mines but before it gets released. This is also contingent on using only a small amount of supplemental energy or fuel for the process, preventing us from solving one problem by creating another.

The second source is methane emissions from a specific type of natural gas fired engines, called “lean burn” engines. There are around 60,000 of these engines across the U.S. “Lean burn” engines were designed to minimize emissions of nitrogen oxides (NOx) and carbon monoxide (CO), which have been regulated for decades. Unfortunately, relatively high methane emissions are released from these engines. ARPA-E needs low-cost, quickly deployable solutions that can be used on a broad range of 2- and 4-stroke “lean burn” engines. These “lean burn” engines vary in their models, sizes, production, and age. ARPA-E needs new ideas on how to retrofit them because it is not economical to replace all these “lean burn” engines.

The third source is methane emissions from the estimated 300,000 flares located throughout the U.S. required for providing safe operations in oil and gas facilities. Flares are specialized equipment that collect hydrocarbon releases from valves and dispose of them by combustion at a safe distance. Most of these are small, and they are designed to achieve 98% methane reduction. ARPA-E’s goal is to increase their performance to 99.5%. This would cut emissions by another 75%. The solutions need to be simple and robust because these flares operate 24/7 in generally remote areas with no personnel. They need to be low cost and operate over a wide range of flow rates and gas composition. ARPA-E needs simple, inexpensive hardware so it can be commercially scalable. The combination of performance and cost metrics makes flare improvements a difficult challenge.

What sort of technological solutions are REMEDY project teams pursuing?

REMEDY’s project teams include research institutions, national labs, universities and private companies whose combined approaches address the broad set of challenges we outlined earlier. We have a handful of teams focused on inexpensive catalysts and new reactor designs for reducing methane emissions from mines. Meanwhile, we also have teams working on novel flare apparatuses, burner concepts, and controllers that could address the majority of flares used in upstream oil and gas production sites across the U.S. Further, we have other teams who are developing technologies that could dramatically reduce methane emissions of existing natural gas engines and improve future natural gas engine designs. It will take a comprehensive approach and a wide range of technical solutions to meet our 99.5% methane conversion target.

What are the challenges related to scaling and commercializing REMEDY technologies?

There are several challenges for REMEDY technologies, the first of which is cost. Any practical solution needs to be affordable. The second challenge is scale. There are hundreds of coal mine shafts, tens of thousands of engines, and hundreds of thousands of flares. The third challenge is the wide range of designs required. Each mine is unique, there are hundreds of engine models, and flare operating conditions cover a huge space in terms of gas composition and flow rate. The fourth and final challenge is that the solutions must be highly reliable and work with minimal operator intervention for years without replacement. It is a tough set of requirements. On the flip side, there is a large market for all three emission sources. If a technology is successful, there will be strong market pull.

What does success mean for the REMEDY program, and how do you measure it? 

We have two broad targets for the REMEDY program. The first metric is to show 99.5% methane reduction while meeting strict overall environmental targets based on Life Cycle Analysis (LCA). The LCA constrains technologies, to avoid “squeezing the balloon” by reducing methane emissions on one hand while increasing environmental impacts on the other hand.

The second metric is cost. Successful technologies must show they can meet the above criteria for less than $40/ton of CO2. The economics incorporate the first cost for the equipment; the cost for consumables such as electricity, supplemental fuel, and catalysts; operating costs and maintenance parts and labor; and the cost of disposing at the end of life. We require very specific inputs so that different technologies can be compared on an equivalent cost basis, since this is how industry will also evaluate the ultimate technologies that come out of REMEDY.