We are all aware of the importance of tackling methane emissions from dairy farming. It is an important goal that can yield faster climate results than decarbonization.
A lot of effort is being driven into research to tackle the enteric emissions, which is the larger contributor to cattle methane footprint. Other approach is to shift part of the demand away from cattle meat and dairy and into plant-based substitutives.
Our approach is different and -regardless of the merits of these other two paths- more immediate and still very powerful: Let´s tackle manure management of small scale dairy farms instead, by removing the need of barn pits, where significant amount of methane generates.
Traditional dairy farming is predominant in the EU. Most of the 40MM dairy cattle in the EU belong to this subsector, that is, are barned in stables of less than 330 cows. The EU average is about 40 cows per barn ranging from 12 in Romania to 187 in Denmark. It is conservative to assume that around 70% of barned cows in the EU store manure in pits for prolonged time.
When manure is spread, or degrades aerobically, the process is exotermic and generates CO2. But when manure degrades in absence of air, the process generates biogas, that is, CH4, H2S, CO2 and water instead.
In such barns, the manure accumulates in barn pits until there is enough to spread it in the fields (where this is allowed) or to deliver it to a treatment center such as a composting plant or a biogas plant.
The problem is that these barn pits are poorly ventilated and manure decomposes spontaneously during storage. The upper manure layers are exposed to some air, and aerobic fermentation also happens, providing the heat required for anaerobic methanation in the lower manure layers. There, in absence of oxygen, degradation is anaerobic and releases methane from the barn pit.
Agrolinera has developed and patented a manure collection technology that digitalizes the manure collection process for small and medium dairy farms to make it efficient and traceable, creating a “virtual sewage” for these dairy communities.
Our system addresses the last mile problem in collection of manure for valorization in biogas plants. We introduce capillarity in the collection process of manure, which we make efficient regardless of barn size. This system collects manure from barns when it is still fresh and fermentation (neither aerobic nor anaerobic) has not started, keeping its energy potential for a biogas plant.
It also allows for the separation of organic matter from the filtrated water at origin to enhance adoption by farmers, who often need the manure to spread in the fields as fertilizer. They can use the liquid fraction (rich in Nitrogen, the fertilizing nutrient) while reducing the logistic cost to the biogas plant, because manure is now concentrated.
As a result, we can prevent barn pit usage (a secondary, but still important source of methane emissions) for small and medium farm sizes (the primary segment of dairy sectors, which owns the broad majority of cows)
The recent development of biogas and biomethane plants in south Europe, which act as valorization points for this manure, this comes as an opportunity to reduce the methane emissions coming from the barn pits of the majority of the dairy sector in the EU, the traditional farmers.
These systems are patented and we are currently building a prototype of the system which will be applied in Asturias, in a pilot project the National Park of Picos de Europa to demonstrate its usefulness for whey collection in a cheesemaking community.
Our next step is to develop the manure collection and separation prototype for manure management and we want to partner with a dairy community who can work with us in this endeavor.