Globally, the agricultural sector is responsible for about 9.3 billion tons of CO2 equivalent (CO2, methane and nitrous dioxide). This amounts to 28% of total greenhouse gas emissions, of which half is the product of crops and livestock activities. Despite these numbers we might not want to give up on the essential sources of food. Perhaps, instead, we need to reconsider the agricultural system we have at present as it faces serious limitations and causes severe harm to the environment.
One step that could be taken is the revaluation of how we manage the agricultural wastes (AWs). The common practices of waste management that are in place now involve tilling, burning of the crop residue, which pollutes the air and leads to soil erosion, and chemical fertilisation, which pollutes the soil. Possibly better alternatives that could foster neutralisation of the damage from the agricultural sector, are organic fertilisation, composting or recycling of the wastes. Specifically, the vegetal wastes, also known as biomass, can play an important role in the agricultural transformation. They have a large potential for the production of biofuel, but also a generous capacity to enrich the soil and increase its fertility and productivity.
In this article we invite you to learn and reflect together with Nullker and the two experts Felix Creutzig and Neil Havermale on the two pathways and philosophies of AW management – generation of new products and regeneration. As the United Nations Economic and Social Council (2017) claims that resource efficiency is necessary for mitigating climate change, the question arises whether resource efficiency should mean for us to generate or regenerate?
At the moment, biofuel, that comes in a vast range of forms (e.g. bioethanol, biohydrogen, biobutanol, biomethane, biomethanol, biodiesel, biochar, biocoal etc.), is offered as one of the alternatives to fossil fuels. It is suggested to be a sustainable, affordable, accessible and renewable energy source that can significantly reduce the amounts of CO2 emissions and mitigate climate change, while increasing countries’ energy independence. Additionally, it is claimed to have potential for solving some socio-economic issues, stimulating social inclusion, generating employment, fostering economic development and reducing poverty.
Biofuel can be produced from plants, crops, manure, sludge, crops residue and diverse forms of agricultural waste (agro-industrial processing, fruits and vegetables as well as livestock waste). Growing plants and crops specifically for energy production is an extremely resource-demanding method and has a large impact on food availability. Utilising the wastes, or biomass, on the other hand, seems to have more prospects.
Annually, around 998 million tons of agricultural waste is produced around the globe, yet, most of it is not treated efficiently. Without proper management, agricultural waste can create environmental hazards, contaminate habitats, and pose risks for human health. Its conversion into energy is seen by many researchers as the most ecological, economical and sustainable approach (Chilakamarry et al., 2022; Pattanaik et al., 2019; Chandra et al., 2012; Saini et al., 2015) and a much better one than burning it down, damping it or leaving it on the field. But is it, indeed, much better?
Different types of biofuels require different methods for their production and for biomass conversion. Pretreatment is the first step in the production system. It allows a better disintegration of biomass, which consequently reduces energy consumption and costs, preserves sugars from degradation and, overall, increases the efficiency of conversion. All of the 5 most commonly used pretreatment practices imply either high costs, high temperatures, chemicals or high energy consumption. Despite that, Awogbemi and Von Kallon claim that pretreatment yields large benefits allowing farm owners to convert their diverse agricultural wastes into useful products of various applications.
Additionally, the biofuel production cycle requires a lot of other processes to be undertaken, large amounts of resources as well as storage and management practices. The given figure below from Biofuels from agricultural wastes. In Second and third generation of feedstocks (Pattanaik et al., 2019) demonstrates some of the processes required for different types of biofuel generation.
Image extracted from Biofuels from agricultural wastes. In Second and third generation of feedstocks (Pattanaik et al., 2019).
Is bioenergy generation from agricultural wastes, then, an effective practice that can yield large benefits? Nullker decided to ask this question to the expert in the field Felix Creutzig. In the words of Creutzig, “Bioenergy has low thermodynamic efficiency and high land intensity, usually (but not always) harmful to biodiversity. Niche applications in the local context, and as intermittent back-up for peak load in winter, can be reasonable. But as a major component of the energy system, I don't see a future”.
Then, what if instead of engaging in all of these actions and transforming the waste into a different product that cannot take up a major role in the energy crisis, we allow natural processes to take over our agriculture?
Such practice is called regenerative agriculture, meaning that the agricultural system follows the natural dynamics and maintains itself (soil, fertility, energy and health) through capturing, harvesting and continuous cycle of natural resources and nutrients. Regenerative agriculture is aimed at maximising the connections between different elements of the system in order to achieve their best synergy, while meeting human needs and opening up access to local communities and economies to the systems’ resources.
Regenerative culture, in its traditional understanding, implies that crop residues degrade and enhance the health of the soil. Removing them can deprive the living soil microbes from food and disrupt the nutrient and soil-carbon cycles. Alternatively, using crop residues as soil amendment can allow degraded soils and ecosystems to restore, increase productivity and mitigate climate change through prevention of additional pollutive activities such as tilling, fertilising and irrigation. When asked, whether for the sake of carbon removal and the environment, including us, it is better to Generate or REgenerate, Felix Creutzig replied, “Regenerate, don't combust. Biochar binds CO2 and improves soil quality”.
We also got in touch with Neil Havermale, the expert on soil carbon economy from Colorado, United States.
In his view, “A regenerative farming system offers a healthy, well-balanced, complex no till cropping system, using site-specific VRT [Variable-Rate Technology] and IPM [Integrated Pest Management] … As a field returns to a healthy condition, the nutrient cycling can change from water-soluble to reliance on nutrient cycling though complex organic molecules and living healthy biome community”.
Neil Havermale also believes that regenerative practices have an indirect positive influence. Studies on “soil health/climate smart sciences, farming systems will evolve. Nitrogen cycling will be shifted from CH4 [methane] and high energy process and distribution to intercrop and relay designs”. Overall, Havermale says that he is for bioenergy if growers are incentivized towards the particular Carbon Intensity concepts. “But the removal of stover for ethanol rather than returning to cover and soil health systems [is] a really bad idea”.
Other researchers, however, like Daniel De La Torre Ugarte and Chad Hellwinckel believe that biofuels could play an important role on the path towards regenerative cultures but only if we treat them as a part of long-term agriculture rather than agriculture as a part of energy policy.
Nonetheless, regeneration is more than just an approach, it is also a philosophy. Thus, Bill Reed truly believes that sustainability alone is not enough. In his view our practices of environmental protection are a mere exercise of “incremental and fragmented efficiency”. We maintain our focus on productivity and health of the environment rather than engaging with its entirety.
Graph from Shifting from ‘sustainability’ to regeneration (Bill Reed, 2007)
For him, regeneration means a co-evolutionary process that happens through integration and engagement of all participants (humans and ‘more than humans’). It is a shift from doing things TO nature to WITH and AS nature. Specifically, he points out that developing a regenerative relationship does not exclude planetary concerns. Instead, the regenerative approach transforms the large-scale issues into “manageable, meaningful and, literally, grounded” acts.
Ultimately, we need to reevaluate our agricultural system to make it healthier, more productive and less pollutant. One step that we can take is to change our agricultural waste management practice. We can choose a path of generation, for instance, producing biofuel from AWs for efficiency maximisation or we can choose a path of regeneration, trusting nature and maintaining the resources we already have.
If you believe in REgeneration, support local communities in their efforts to restore ecosystems around the world by choosing one of the Projects on Nullker’s donation platform! Work WITH people and WITH nature!