Founder and Chief R&D of A Healthier Earth, Alastair Collier, thinks livestock farmers should be incentivised to cut methane emissions in a similar manner to sequestering carbon — using credits.
For the last 30 years, climate conversations have focused on the urgent need to cut carbon dioxide emissions. But it’s not the only greenhouse gas. Making up nearly a third of all emissions, methane is the second biggest contributor to global overheating.
Reducing methane emissions is one of the fastest ways of slowing rising temperatures. It’s critical for keeping the world on track to meeting the Paris Agreement of limiting global warming to 1.5°C and preventing climate breakdown.
Consequently, methane is to be an important topic in talks at the United Nations’ climate summit COP28, taking place in Dubai, the United Arab Emirates. In fact, China and the U.S. have agreed to rally other nations into having a summit on methane with a view to coming up with concrete plans for its global reduction. This can’t happen soon enough. As a matter of urgence, we must address the two root causes of our methane problem: fossil fuels and agriculture.
While it’s clearly essential that we tackle the emissions caused by the oil and gas industry, those from farming cannot be ignored. Accounting for a third (32%) of human-caused methane emissions and 14% of all greenhouse gas emissions, they primarily come from cattle.
Bovine manure and gastroenteric releases are the main problems. A single cow releases between 70-120kg of methane per year, mainly through burps.
Reducing animal farming’s methane emissions is fundamental to tackling the climate crisis, but, to date, there has been little incentive for farmers to do so. Instead, the investment focus remains on CO2 reduction, due to the increasingly competitive and attractive international carbon market. But, with methane such a rapid driver of rising temperatures, this must change.
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The carbon market must be expanded to include methane too, so investors can buy and sell methane credits alongside carbon ones.
For this to happen, investment needs to be attracted with scalable and practical agricultural solutions that can make quantifiable methane reductions. Thankfully, one already exists. Biochar is a form of charcoal that’s created in a process called “pyrolysis” when organic materials — like biomass waste — are heated in the absence of oxygen. It is more commonly used as a soil additive — not only improving soil fertility, but also sequestering carbon out of the atmosphere. However, biochar can also be added to livestock feed, to improve animal health by increasing nutrient intake and decreasing the methane emissions caused by ruminant digestion.
In practice, biochar reduces the concentration of methanogens — the microorganisms that generate methane for food decomposition — in cows’ stomachs by absorbing them into its porous structure. Scientific studies have proven its efficacy. Australian researchers found that biochar diminished enteric methanogen concentrations in dairy cattle by 30%. Meanwhile, research into beef cows on the U.S.’ Great Plains found that adding biochar to feed reduced methane emissions by as much as 18.4%.
Biochar can also be mixed with manure and slurry when they need to be stored. Not only reducing ammonia and odours, it also cuts emissions in terms of both methane and nitrous oxide, another greenhouse gas. Scientists at the University of California conducted a study showing that adding just 6% of biochar to dairy manure results in an 84% reduction in methane emissions during composting.
On a global scale, this means that biochar could double the climate change mitigation potential of dairy manure management. Considering that there are around 940 million cows on the planet, this represents a significant opportunity.
For livestock farmers to realise biochar’s amazing potential, they need to see the value it can bring to their operations — both financially and environmentally. The way forward is to incentivise them to cut methane emissions in the same way they are incentivised to sequester carbon, via carbon credits. In most people’s minds, expanding the carbon market to include methane might not be the most pressing climate solution — but it could be the very thing that helps bring us back from the brink of irreversible climate tipping points. To make that dream scenario reality, we need to ensure farmers use proven solutions, like biochar, to cut their methane emissions.
A Healthier Earth is a climate-tech involved in biochar projects. It was also the official biochar partner of COP28.