Methane represents 63% of New Zealand’s carbon footprint (including non-agricultural sources) and 90% of this is agricultural methane. Aotearoa New Zealand has pledged to decrease its biogenic (cow-produced methane) methane emissions by 10% by 2030, however there is no existing economically viable solution.
“The biofilter options we are exploring already exist, but they are too large and too expensive to be used on farms, our research aims to prove that we can remove agricultural methane in a cost efficient and sustainable way.
“For these biofilters to work the methane must be captured so microorganisms can eat it, this requires cows to be in barns for all or part of the year, ideally this would be over winter which would also prevent nitrate leaching into the ground and waterways.”
The microorganisms in the biofilter don’t die from too much methane, in fact they perform best when there is too much methane. “These microbes in the biofilter like to gorge themselves, they prefer having an abundance of food available as they will continue to eat methane until they are full, they then convert the methane to CO2 which is released back into the atmosphere.
“The CO2 is carbon neutral however it can’t be captured and reused as the microbes will be releasing such small amounts it would not be cost effective,” Professor Gostomski says.
Not only is this research important for New Zealand’s environment and economy, it could also be sold and used across the world, particularly in places like the United States where there are more barn-housed animals.