The Impact of Dairy Farming on the Environment
Based on results of a 2008 study, the US dairy industry produces an average of 2.05 kg of CO2 per litre of milk consumed (Thoma et al., 2013). Of this, 72% is accrued up to the farm gate. This means that there is much to be done in terms of increasing efficiency at the farm level in the form of biogas digesters and in silage production.
This highlights the significant opportunity for the industry in on-farm improvements, specifically in terms of manure management and controlling enteric methane emissions. These emissions sources, as well as the incoming burden of the feed, are significantly influenced by the on-farm feed conversion efficiency. (i.e. how easily the cow digests the feed supplements). Improving conversion efficiency reduces GHG (greenhouse gas) emissions from all three sources’ (Thoma et al., 2013). To put this figure in perspective, a carbon footprint audit of the Pepsi Cola group’s Tropicana orange juice line revealed a footprint of 899 g of CO2 per litre. This is 57% less than the US dairy output.
Eighty percent of the waste in dairy farming is considered to be recoverable with existing technologies. However, there is a big deficit in the adoption of these sorts of technologies. In 2014, of the 1,496 dairies in the state of California, only 26 farms had biogas technology installed. Of these, 17 had ceased using the equipment. A thesis by Desireé Lee Libarle explores impediments to the adoption of technologies in the dairy industry. Reasons for the low uptake of emission-control technologies in California included ‘[the] initial costs of implementing combined with low negotiated energy prices and changing emissions regulations’.
The successful adoption of emission-control technology has been seen in the Netherlands, however. There, dairy farmers, aided by considerable investment from the Dutch government, have begun to explore the benefits of biogas technology.
The shift towards intensive dairy farming could account for small farmers’ hesitation in investing more in this technology.