Case Study: "Klimamilch" - produce less carbon intensive milk by integrating a circular biogas approach

This article is based on a consulting engagement we did last year for a biogas company in Germany. We believe it highlights amazingly how existing systems can be improved to accelerate our transition towards a net-zero future. The topics covered include some basics of dairy production, how one can create biogas from cow manure and how to close the circular energy approach. Just for clarification I'd like to point out that this proposed system is yet to be implemented in practice, we do not know a large scale project that actually got implemented.

First some basics: Dairy production usually involves the following steps:

1. 1. Feed is produced (needs fertilizer)
2. 2. Feed gets transported
3. 3. Cows are feed and milked
4. 4. Raw milk is transported to dairy factory
5. 5. Milk is processed (needs a lot of heat)

Conventionally all of these steps need additional input. Fertilizer, fuel and gas for heating are partly to blame why dairy products have such a high carbon footprint (the other reason, not explored here, is that cows produce methane while digesting, which is worse than CO2 from its greenhouse warming effect).

The proposal - integrate biogas as circular energy solution

Biogas refers to a biochemical process where organic matter decomposes in a sealed environment without access to oxygen. This process releases various gases (methane, ethane..) that can be captured and refined. The resulting gases, once refined, are chemically identical to gas from fossil sources and can replace them 1 to 1.
This process has or used to have kind of a bad reputation among environmentally aware groups because if it processes biological mass that was farmed specifically for this purpose it displaces land that would otherwise be used to grow crops for humans, and in the worst case creates incentives for deforestation
Luckily with bigger biogas refineries it becomes energetically feasible to run this process with mostly manure and dung. These are byproducts of any kind of animal farming and dairy farming specifically provides a great input for this approach.

By adding such a biogas refinery into the dairy factory cycle we can solve a variety of issues. The cows produce manure which is refined and turned into bio methane and liquefied natural gas (LNG). The first can be used to substitute fossil gas needed for the heat in the milk processing step. The LNG can be used to run trucks and tractors in the transportation steps. And lastly one of the byproducts of the biogas process serves as a great substitute for the conventional nitrogen fertilizers used in growing the animal feed.
The case study concluded that this can reduce the carbon footprint of the milk by up to 30% compared to a conventional production. This is big considering the overall size of the footprint of dairy related foods.
Apart from the obvious environmental benefit this circular approach provides, we went one step further. Taking the grocery retailers and consumers into the viewpoint, we identified additional opportunities for both dairy factories and retailers - hopefully increasing the incentives to adopt such systems in the future.
Retailers:
Many have set ambitious science based targets for emission reductions and they need to reduce the footprint of their input products (scope 3 emissions). Such a climate milk can be a significant lever here.
Dairy factories:
Sustainability has been a key part of many brands marketing, also in the dairy industry. Conventional brands have been losing market shares to plant-based alternative i.e. oatmilk for a while now. Positioning themselves as a sustainable dairy brand not only by words but by actual emissions reductions will help them keep up with the competition.
Secondly retailers with science based targets at some point will have no choice but to restrict themselves to purchase only from suppliers that reduce emissions themselves. Dairy factories might be forced to adopt this sooner or later - and we believe early adopters to have a clear competitive advantage in 2-3 years.

To summarize this is a great opportunity for early adopters in the dairy industry, we are happy to connect to a project developer who can help with the implementation of such a circular approach.