Agriculture as provider of both food and fuel

The road from project idea to scientific publication is normally a process that takes at least one year and often longer. In the spring of 2008 food prices rose markedly around the world. Production of ethanol for vehicle fuel was pointed out as one of the causes. My colleague Simon Snowden from Liverpool Management School had just shown that 60 per cent of the price of milk in the UK was directly coupled to the price of oil. We had begun to discuss if it really was ethanol production that had caused the food price rises or whether it could simply be the price of oil instead.

Here are some articles that show just how inflamed the issue was in the spring of 2008. First CNN and “Riots, instability spread as food prices skyrocket”, and here is another article on the subject: “Why Are Global Food Prices Soaring?” Let me conclude with this article from BBC’s home page: “Bioenergy: Fuelling the food crisis?”.

We looked for someone who wanted to do a Master thesis on the subject at the same time as we made sure we had access to expert advice in the person of Professor Lars Ohlander at SLU [Swedish University of Agricultural Sciences]. In June 2008 Kersti Johansson and Karin Liljequist began their thesis work “Agriculture as provider of both food and fuel” and it became a “mammoth” project.

Our starting point was that food is energy and that it requires energy to produce food. The energy unit that one normally uses when discussing food is the calorie. According to Swedish authorities we should consume an average of 2,500 kilocalories per person per day. If you are engaged in physical work then you need more calories than if you are sitting in an office in front of a computer. The standard unit for energy is the joule (J) but other units that are used are the calorie (cal), volt-ampere-second (VAs), watt hour (Wh) and electron volt (eV). In the oil industry they use the unit “oil equivalents” that is the amount of energy in a barrel of oil. The Energy Authority gives Sweden’s energy use in units of TWh, terawatt hours.

We collected the data in this way: “Statistics on agricultural production were taken from the database of the Food and Agriculture Organization of the United Nations (FAO). The data used refer to the world production in year 2006 and includes 129 different crops”.

What we calculated: “The constructed database includes data on agricultural production for every individual country, making it is possible to calculate the energy content of crops and residues for any region. We chose to present results for both the world and the 27 member states of the European Union, hereafter referred to as EU27, since it plans to significantly increase the amount of biofuel in the transport sector within the union”.

In May 2009 Kersti and Karin had finished their thesis work (read the master thesis) and we decided to take it further and to write a paper for publication. It was necessary to condense a very detailed piece of work down to the right length for a publication. In October 2009 we were able to submit the paper to the journal Ambio. Then followed the peer review process and a few small changes had to be made before it was accepted for publication and, finally, published online on April 16, 2010.

In the past two years we have had 15 articles that have gone through a similar process and we have a number that are in various phases of the process described above.

When the study was conducted there were 6.7 billion people on Earth and that means that we then needed to eat food with a total energy content of 7,100 TWh per year - or, if we express it in oil-based units it is 12 million barrels oil equivalents per day. Let’s read the abstract from the article:

A database of global agricultural primary production has been constructed and used to estimate its energy content. The portion of crops available for food and biofuel after postharvest losses was evaluated. The basic conditions for agriculture and plant growth were studied, to ensure sustainable scenarios. The net energy contents for the world and EU27 was found to be 7200-9300 and 430 TWh respectively, to be compared with food requirements of 7100 and 530 TWh. Clearly, very little, or nothing, remains for biofuel from agricultural primary crops. However, by using residues and bioorganic waste, it was found that biofuel production could theoretically replace one fourth of the global consumption of fossil fuels for transport. The expansion potential for global agriculture is limited by availability of land, water and energy. A future decrease in supply of fossil energy and ongoing land degradation will thus cause difficulties for increased biofuel production from agriculture.

Ambio is the journal of the Royal Swedish Academy of Sciences. It is published by Springer. Here is the link to the journal and here you can read our copy of the article (PDF 204KB).

At the moment the world produces sufficient food for its human population but we know that much food is wasted. How much is difficult to calculate. As well, the distribution of food in the world is not just.