The use of biogas generated from organic material is an effective mechanism to significantly reduce the noxious effects of anthropomorphic methane accumulation and a highly efficient method in ensuring that the carbon footprint of industrial activities, especially those related to waste management, can be minimised.
On a global scale, over one third of all food produced is lost or wasted along the management chain. If only biogas production, caused as a direct result of the production of food for human consumption is considered, it could mitigate greenhouse gas emissions equivalent to 510 to 560 Mt CO2. Put into context, this represents avoided emissions from the production of fossil fuel-based electricity emissions equivalent to those of the United Kingdom.
Unfortunately, even though there have been sterling efforts to reduce organic material going to landfill, much of it still does. The subsequent degradation of this material represents a considerable contribution to greenhouse gas emissions and other environmental issues, such as the contamination of groundwater.
As the human population agglomerates around urban centres and grows, the tendency is towards intensive farming, and cities acquire a greater carbon footprint because of the demands of consumption. But, instead of seeing these stark facts as a harbinger of doom, it could more usefully be looked at as a challenge for humanity, and also as an opportunity. Many countries around the world have developed large-scale techniques, such as anaerobic digestion, in which organic material from both agriculture and food waste are not waste but are converted into useful ‘after-purpose’ products. A report recently published by the World Biogas Association (2019) indicates that, currently only 2% of the global capacity for biogas is being captured.
The potential is, therefore, considerable and it is an objective of an increasing number of governmental initiatives to ensure that organic material is not wasted as it moves along the supply chain. Rather, the emphasis is changing, albeit slowly, towards collection and proactive management to ensure that waste is minimised and, rather than being sent to a shallow grave, the preference is to collect it in anaerobic digestors and convert it into biogas, a useful product that not only removes a harmful greenhouse gas from the atmosphere but, in creating a fuel for use in power generation, use of biogas displaces the use of fossil fuel to generate that same power, a classic double-whammy.