29 January 2023 |

Cutting emissions from cows


We often discuss methane emissions in this newsletter. They’re an important leverage point to slow global warming. It’s not all about CO2: Methane emissions account for up to 30% observable of global warming. Cutting CH4 would be a great way to buy more time to decarbonize other sectors.

Easier said than done. A lot of money is pouring into solutions that offer better monitoring of methane leaks and emissions from pipelines and the like (see a Series A fundraise for Kuva Systems from this week). Even major oil & gas companies are focused on curbing methane emissions. Still, methane emissions are increasing rapidly and come from many different sources, including natural systems, which aren’t always easily tracked.

All that said, there’s no doubt about agriculture’s status as a huge contributor to methane emissions. And within ag, methane emissions from enteric fermentation – i.e., the process that helps cows digest cellulose – are among the largest contributors. In the U.S., cows account for ~20% of total methane emissions

In the (sea)weeds

Fortunately, the problem of methane emissions from ruminants – especially cows – isn’t new news. Many firms and teams are working on solutions. These range from various types of feed additives to vaccines. 

In the first category, Rumin8 raised $12M in a second phase of seed funding this week to make synthetic bromoform (the active ingredient in red seaweed). When added to ruminants’ diets, this compound could help reduce methane emissions. Purportedly – and under pretty specific conditions, I’m sure – the methane reduction rate could be as high as 95%. While that number likely includes rosy assumptions, even 30-40% reductions would be a big win. 

To back up on the biology, methanogens are prevalent in the rumen (the first stomach compartment of ruminants) and help animals like cows digest grass. They create methane as a by-product of the animals’ normal digestion processes, which they then excrete in various ways. Successful emissions-reducing feed additives aim to act as methanogen inhibitors, disrupting the methane production process in digestion while not harming the overall digestive process.

Cows in the Netherlands, ground zero for aggressive climate policy in agriculture (photo by Leon Ephraïm)

Rumin8 isn’t the first to research and develop feed additives to reduce ruminant methane emissions. It’s not the only one to use seaweed, either. Symbrosia is another firm that comes to mind, and many academic studies have been published exploring the merits of seaweed in the past 3-4 years. Approximately half of all investment in seaweed since 2019 has gone into two sectors, methane reduction being one of them (bioreactors being the other). 

Nor is seaweed the only approach on the feed additive front. Other firms, like Mootral, which we covered last year, use other common ingredients like citrus and garlic.  

And, as we alluded to earlier, other firms, like ArkeaBio, are working on fundamentally different approaches to tackle cow’s methane emissions. Arkea is working on a vaccine to reduce methane emissions from ruminants and recently raised funding. 

The net-net

Breakthrough Energy Ventures led Rumin8’s fundraising round. It also led ArkeaBio’s funding round. I reckon they’d agree with me in acknowledging that this isn’t going to be a winner-take-all-space. With dozens of firms developing products, there will hopefully be several that work on the market soon. Some will probably work better in different environments, with different types of cows (there’s plenty of diversity between cows worldwide), or combined with specific diets. And perhaps domestic farmers will start with domestically produced products. 

Zooming out, folks (myself included) get in such a tizzy arguing about the energy transition that we often get distracted from problems that can be solved without a complete societal overhaul. Methane emissions from ruminants are a good example. Reducing emissions in this arena should be feasible with little impact on consumer behavior. 

Ideally, in a decade, we’ll view methane emissions from ruminants like we view the ozone layer now. It was a problem. We figured out solutions. We started implementing them. And now, things are getting measurably better.