Prevention and Abatement of Methane Emissions
Traditional 100-year metrics for measuring greenhouse gas emissions show that methane is a potent greenhouse gas with a global warming potential (GWP) 28-36 times greater than carbon dioxide (CO2)[A]. While this may be the case on a 100-year scale, many researchers actually recommend using a 20-year metric because methane has a relatively short life (roughly 9 years) in the atmosphere. Using this shorter lifetime increases methane’s GWP to 84-87 times greater than CO2, and shows that there is an opportunity to focus on other reductions in emissions from sources other than CO2 to lower greenhouse gas emissions as a whole.
Given the potential impact of reducing greenhouse gas emissions specifically through methane reductions, ARPA-E recently released a Request for Information (RFI) for technologies focusing on preventing and/or abate methane emissions. We sat down with ARPA-E Program Director Jack Lewnard to learn more about the RFI and ARPA-E’s interest in potentially creating a program in this space.
Why does ARPA-E want to focus on methane emissions?
The Environmental Protection Agency’s Greenhouse Gas Inventory (GHGI) shows that methane accounts for 23% of US anthropogenic greenhouse gas emissions[B]. Using the 20-year GWP, methane emissions are 1.83 Gt CO2e per year, so methane emissions need to be addressed.
Although methane emissions are smaller than CO2 emissions, in some cases methane emissions may be easier to prevent or abate than CO2. ARPA-E’s proposed program compliments ongoing CO2 reduction efforts. If there is a carbon credit program in the future, new approaches targeting methane could provide the US with lower-cost options to decrease its greenhouse gas inventory.
Part of ARPA-E’s mission is to explore new technology spaces and seek novel solutions that can have a significant impact. This RFI shows that ARPA-E recognizes that while there are many R&D programs addressing CO2 emissions as part of greenhouse gas reduction programs, there has not been as much spending focused on non-CO2 greenhouse gas emissions. Additionally, this potential program could also be ARPA-E’s first foray into the less-explored topic of non-CO2 emissions.
What would ARPA-E hope to achieve regarding methane emissions?
We’re looking to find solutions that can reduce methane emissions from a wide range of sources by 90%. Proposed solutions must have a cost that is equal to or lower than the cost to remove an equivalent amount of CO2 using processes such as carbon capture and sequestration. We also need to ensure that the solution’s “environmental footprint” is acceptable, in terms of land use, water requirements, and air impacts.
Sounds ambitious – what approaches are you considering?
We’re open to all options – but specifically are looking for solutions that:
- Prevent methane emissions from anthropogenic activities. In other words, solutions which intervene before anthropogenic emissions escape to the atmosphere.
- Abate methane emissions at their source. Sources include vents, leaks, and exhaust stacks.
- Remove methane from the air. As mentioned above, methane only lasts about 9 years in the atmosphere. Nature is very good at getting rid of methane using reactions in the atmosphere and methanotrophs in the soil. Maybe we can learn from Nature, and help her out.
So you’re looking broadly for solutions. Do you have specific technologies in mind?
To some degree, industry is already working in this space and making progress reducing methane emissions, so we don’t want to duplicate those efforts. However, we think there are other opportunities to further reduce costs through innovative approaches that have not previously been considered by the private sector. Given the wide range of methane sources, we believe that we will need to explore a wide suite of technologies to address this issue. Right now since we’re just starting to think about this program we’re open to all options, with some examples of these potential technologies (but by no means a complete list) including:
- Prevent methane from escaping from orphaned wells, leaking plugged wells, and/or coal mines. Options include new materials or techniques for sealing the sub-surface, and/or biological intervention to “consume” the methane before it gets to the surface.
- Reduce methane “burps” from ruminants, using novel genetics, nutrients, and/or enteric consortia modifications.
- Oxidize methane to CO2 using catalysts, particularly non-platinum group catalysts, and/or techniques that expand the operating range of catalysts. There’s been some very interesting work using photo-catalysis, electro-catalysis, electrochemical-catalysis such as NEMCA, and plasma-assisted catalysis to oxidize methane.
- Increase methane combustion efficiency of gas-fired reciprocating engines and flares with better mechanical designs and/or chemical additives.
- As mentioned above, accelerate natural processes such as tropospheric reactions and methanotropic activity in soil.
Who do you think can help?
At ARPA-E we consistently see the best results come from diverse multi-disciplinary teams. As mentioned above, we view this area as under-explored. However, there are many researchers and companies with expertise in pertinent areas, including expertise in materials, chemistry, biology, reactor or engine design, etc. We want people to think creatively and re-imagine how their expertise could be applied to the task of preventing or abating methane emissions. For example, a lot of R&D funding has been spent to directly convert methane to high-value products like methanol. Creating CO2 through those programs has been viewed as a failure, but that same failure would be a success for this problem. Biologists and atmospheric chemists know many intricate details for natural methane attenuation. We’re asking ‘How can they focus that knowledge to accelerate these natural processes?’
Potential solutions also will ultimately need to be crafted into a commercial package, and we need the deep technical experts involved in this commercialization potential. Solutions will also need sensors to measure methane upstream and downstream, and to control the process. We need experts who understand the details of the methane sources and companies who know how to operate in areas ranging from oil and gas exploration to dairy. It will take a really skilled and diverse team to crack this problem, but that’s what ARPA-E programs are all about.
Where can people find out more about this potential new program space?
There’s the RFI itself, which we’re looking to get responses to by October 15, 2020. We’re also planning a virtual workshop on October 20, 2020.
Additionally, if this RFI progresses to a full program we’ll be putting out a teaming list for researchers and organizations who are looking for partners, so stay tuned for updates in this as we progress in exploring the space. We’re all learning together as we explore this area, so I hope that anyone interested in the space will attend the webinar and reach out to the ARPA-E team should they have any questions.
For more on ARPA-E’s open funding opportunities and requests for information, visit the ARPA-E Funding Opportunity eXCHANGE.
B) United States Environmental Protection Agency (US EPA) Green House Gas Inventory, 2018.