Yesterday’s introduction to today’s essay was predominantly the film made by Rebecca Hosking investigating how to transform her family’s farm in Devon into a low-energy farm for the future. Rebecca discovering, unsurprisingly, that nature holds the key.
The film highlighted the degree to which our modern system of food production and distribution is dependent on oil. I am sure that Jean and I were far from alone in not fully appreciating just how much oil is used in agriculture. Let’s start with the UK.
Following the oil crisis in 1973, a book was published in 1978 by B.M. Green under the title of Eating Oil (1). In 2005, Norman Church wrote an essay over at the website 321energy.com in which he referred to that book. Here’s some of what he wrote.
The aim of the book [Eating Oil] was to investigate the extent to which food supply in industrialised countries relied on fossil fuels. In the summer of 2000 the degree of dependence on oil in the UK food system was demonstrated once again when protestors blockaded oil refineries and fuel distribution depots. The fuel crises disrupted the distribution of food and industry leaders warned that their stores would be out of food within days. The lessons of 1973 have not been heeded.
Today the food system is even more reliant on cheap crude oil. Virtually all of the processes in the modern food system are now dependent upon this finite resource, which is nearing its depletion phase.
The article is a ‘must-read’ for anyone who wants to understand better the approaching crisis and the madness of present behaviours. Take this, for example (my emphasis):
One indicator of the unsustainability of the contemporary food system is the ratio of energy outputs – the energy content of a food product (calories) – to the energy inputs.
The latter is all the energy consumed in producing, processing, packaging and distributing that product. The energy ratio (energy out/energy in) in agriculture has decreased from being close to 100 for traditional pre-industrial societies to less than 1 in most cases in the present food system, as energy inputs, mainly in the form of fossil fuels, have gradually increased.
However, transport energy consumption is also significant, and if included in these ratios would mean that the ratio would decrease further. For example, when iceberg lettuce is imported to the UK from the USA by plane, the energy ratio is only 0.00786. In other words 127 calories of energy (aviation fuel) are needed to transport 1 calorie of lettuce across the Atlantic. If the energy consumed during lettuce cultivation, packaging, refrigeration, distribution in the UK and shopping by car was included, the energy needed would be even higher. Similarly, 97 calories of transport energy are needed to import 1 calorie of asparagus by plane from Chile, and 66 units of energy are consumed when flying 1 unit of carrot energy from South Africa.
Just how energy inefficient the food system is can be seen in the crazy case of the Swedish tomato ketchup. Researchers at the Swedish Institute for Food and Biotechnology analysed the production of tomato ketchup (2). The study considered the production of inputs to agriculture, tomato cultivation and conversion to tomato paste (in Italy), the processing and packaging of the paste and other ingredients into tomato ketchup in Sweden and the retail and storage of the final product. All this involved more than 52 transport and process stages.
1: Green, B. M., 1978. Eating Oil – Energy Use in Food Production. Westview Press, Boulder, CO. 1978.
2: Andersson, K. Ohlsson, P and Olsson, P. 1996, Life Cycle Assessment of Tomato Ketchup. The Swedish Institute for Food and Biotechnology, Gothenburg.
But, surprise, surprise, it’s no different here in the USA!
Dale Allen Pfeiffer‘s (1) book Eating Fossil Fuels: Oil, Food and the Coming Crisis in Agriculture makes it clear (my emphasis):
The miracle of the Green Revolution was made possible by cheap fossil fuels to supply crops with artificial fertilizer, pesticides, and irrigation. Estimates of the net energy balance of agriculture in the United States show that ten calories of hydrocarbon energy are required to produce one calorie of food. Such an imbalance cannot continue in a world of diminishing hydrocarbon resources.
1: Dale Allen Pfeiffer is a geologist and writer from Michigan, U.S. who has investigated and written about energy depletion and potential future resource wars.
When we think of the problems associated with peak oil, our first thoughts may turn to transport, electricity, or plastics. The use that tends not to come to mind, yet could be the most devastating of them all, is agriculture.
The Diesel Farm
Tractor Oil and gas are essential to modern farming. The most obvious use is to run the tractors and machines. Car drivers can switch to public transport, lorries can move their goods (partially, at least) to railways, but the only option for a tractor or combine harvester is a horse or an ox. Clearly modern agriculture could not switch to an animal-power-based system and hope to continue with modern yields. A tractor can plough in an hour an area that a horse would take a day to (0.9–1 hectare). The horse also needs more skill and you have to put aside some of your crop to feed it. Imagine trying to gather the harvests of the vast fields of maize and wheat of the USA using only horse- and human-power.
But diesel is only one of the uses for oil and gas. Another, possibly more important use, is petrochemicals.
Nitrogen is one of the most important elements in fertilisers. In the most common method, the Haber-Bosch process, hydrogen is combined with nitrogen to form ammonia. It requires high temperatures and strong atmospheric pressure, therefore a great deal of energy. The nitrogen is taken from the atmosphere while the hydrogen is obtained from natural gas. The process became economical in the 1920s and since then, fertilisers have become indispensable. Worldwide use of commercial fertiliser more than doubled between the late 1960s and early 1980s.
The use of fertilisers allows farmers to grow the same crops each year, rather than rotating (previously farmers planted fields with legumes that restored nitrogen to the soil.)
Oil and gas are also used in the production of many herbicides and pesticides.
1: There is a note from Paul on the home page, “I created this site several years ago and do not have the time any longer to keep it updated. Therefore you will find that the data is only relevant up to around 2006 and some of the links will no longer be correct. However the principles of peak oil still apply and I have left the site online as a useful introduction to the problem that hasn’t gone away.”
Alright! That’s enough to upset anyone!
Thankfully, there are a number of positive moves going on all over the world and tomorrow I will conclude the essay with details of those positive happenings!
In the meantime, think about what you eat!