Methane Capture: Can it be done?

Image: ‘Pollution’ byu Billy Wilson is licensed under CC BY-NC 2.0

Carbon dioxide emissions have long been targeted by researchers and policymakers as the key culprit of global warming. However, scientists are now turning their eyes to capturing methane (CH4), a short-lived climate pollutant which accounts for 30% of the rise in global temperatures since the industrial revolution. Although methane remains in the atmosphere for only 12 years while carbon dioxide stays for centuries, methane heats the air far more during its presence. For the first 20 years of its release into the atmosphere, a methane molecule possesses 80 times the warming power of one carbon dioxide molecule. 

The potency of methane means that capturing it while it is still in the atmosphere is crucial for mitigating global warming in the near term. 

Where methane comes from:

Direct human activity accounts for about 60% of atmospheric methane emissions. Agriculture is the largest contributing sector to methane emissions through livestock gastroenteric releases and paddy rice cultivation. The energy sector, particularly the extraction, transportation and usage of fossil fuels, is the next largest emitter. 

Emerging technologies:

Numerous technologies have emerged for methane capture. Californian start-up Windfall Bio is growing methane-eating microbes for use on dairy farms, landfills and wastewater facilities. These microbes combine methane and nitrogen from the air to produce an organic fertiliser. In March 2023, the company raised 9 million US dollars for their solution. However, such success stories are few and far between as methane capture solutions face the twin hurdles of technical and commercial feasibility. 

Methane removal is chemically more complex than carbon dioxide removal, yet its research lags far behind. Several technical problems hinder the feasibility of existing solutions. For one, the lower concentration of methane in the atmosphere compared to carbon dioxide means that removing methane involves processing large volumes of air, which is energy-intensive. Additionally, some technologies release side products, including chlorine and carbon dioxide, which also contribute to global warming. Research on the solutions has a long way to go before effective and scalable solutions come to fruition. 

Financing challenges:

Methane capture solutions also face the Herculean feat of turning capital in their favour. According to the Climate Policy Initiative (CPI), financing for methane abatement solutions is severely insufficient and misdirected. According to a CPI report, the fossil fuel sector has received the lowest amount of methane rebatement finance despite having the highest potential for methane mitigation by 2030. The report also states that almost two-thirds of methane abatement funding was directed towards the waste sector, but 82% of human-caused methane emissions originated from activities in the fossil fuel and agriculture sectors. These financing gaps could mean that technological solutions cannot be scaled up to make a difference if and when they are developed. 

Given the gaps in technology and funding, it is urgent and vital for methane capture to come into the policy limelight. Much needs to be done before methane capture solutions are implemented at a meaningful scale that can make a difference in climate change mitigation.