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Eating fossil fuels - Failing food security
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| Silage windrows in a field in Brastad, Lysekil Municipality, Sweden. Credit: W.Carter (CC0 1.0) |
Multiple stressors are converging to make the current industrial food system increasingly unsustainable and vulnerable to perturbations. Of course, the food system is in and of itself a leading cause to what is now threatening its future survival. Climate disruption, freshwater depletion, biodiversity loss, soil erosion and falling EROI on fossil fuels all point to the demise of industrial agriculture. This is well understood by biophysical economists and systems ecologists but often neglected in public or political discussions about food security. Most agricultural policies worsen the problem by making small-scale local agroecological farming unprofitable. Thus dooming large swathes of the population to become reliant on a dying system that costs more than it provides in terms of surplus energy.
There is a big misconception in the world about how modern technology has made us more efficient in agriculture. We think that big machines and lots of fertilizers are a better use of resources than employing more people. While large scale farming may seem efficient at first glance our perceptions are opposite of reality. How efficient the production of food is depends on the amount of energy expended on its development. The EROI, Energy Return on Investment, shows us the true nature of our efficiency in producing and consuming food.
In hunter-gatherer societies, the relevant EROI metric is the caloric value of the food captured or gathered, versus the caloric expenditure of the hunt or gathering expedition. Studies of hunter-gatherers show an EROI of 10:1 to as high as 50:1 (Glaub 2015, Glaub & Hall 2017) depending on effort and final consumption. Large prey eaten directly by the hunting party only would yield a large energy profit while meat provided to support the hunters families would yield lower EROI ranging between 16:1 to 6:1. Nevertheless, this relatively large energy profit ratio probably allowed for the leisure time often associated with gathering societies. But limited capacity for food storage and settlement hinders development of a larger society.
High population and overexploitation of resources was likely a driver of early domestication. In pre-industrial agriculture, dependent on peasant farmers, the EROI was 5:1 or less (Day et al. 2018) as it required intense efforts over long periods with often variable results. Much time was spent on production of food, fodder and fuelwood. But farming had the benefit of food storage which led to established settlements and concentrated labour. Fuelling population growth and specializations.
Early industrialized societies benefited from high EROI from fossil fuels and large energy surpluses. Capital and energy substituted for labour. Food, fodder and fuel could be provided with fewer workers, permitting an expansion of non-primary sectors. The range of goods and services expanded. In the United Kingdom, energy and food expenditures fell to 20% as a proportion of GDP in 1830 from 50-80% prior to the industrial revolution (Day et al. 2018). But EROI of global oil reached its maximum value of 50:1 in the 1930s and has fallen since then to about 10-15:1 today (Court & Fizaine 2017). Modern industrial high-tech agriculture now consumes a staggering 10 calories of energy for every calorie of energy (food) delivered to the market, i.e. EROI of 1:10. Rending much of agriculture a net energy loss and completely unviable without fossil fuels.
As EROI of fossil fuels continues to fall an increasing amount of energy will be needed simply to provide energy and food to society. Leaving less energy over for other sectors of the economy such as education, health care etc. The only way to get out of this trap is to switch to renewable energy sources and promote small-scale, local, agroecological food production that can generate high yields but in a more diffused manner. Just like renewable energy technologies. Thus there needs to be a transition from centralised to decentralised energy and food production. Very few believe we can replace all fossil fuels with biofuels or electricity, especially in the agricultural industry that is very reliant on diesel as transport fuel. Furthermore, even if some farms could make such a shift in fuel use they would still be unsustainable if they continue to erode soils, eradicate biodiversity, deplete freshwater sources and pollute the environment. Even FAO recognizes this dilemma and now promotes agricultural practices in line with ecosystem-based management.
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