Think Food and Fuel!

27^th November 2015

We tend to argue at length about issues we encounter every day, whilst we make quick decisions about far-reaching issues of which we have limited understanding, such as climate change, or food security. Whilst eating and drinking keeps body and soul united,we become deeply emotional when it comes to food,. We welcome genetically modified organisms (GMOs) when they provide better quality and more affordable medicines, but the idea of GMOs food crops frightens us. Whenever I mention bio-fuels, I encounter rapid dismissal and concerns that they are a “crime against humanity”. But do we really have a food production problem?

The year 2008 was a turning point for bio-fuels as they were blamed for the 2007-2008 global food price crisis. In the same period the world saw a sharp increase in the oil price and it was largely overlooked that energy and food supply are closely linked. In addition, the mortgage crisis in the US led banks and hedgefunds to speculate in agricultural commodity futures, which made things worse. So do we have a food security issue, or is sustainability mainly dependent on affordable energy ready on demand (and not when the sun shines or the wind blows)?

An average UK household with two adults and two teenagers consumes approximately 30,000 kJoules of energy from food each day, that’s the energy contained in just 1 litre of crude oil! Given a worldwide crude oil production of 80 million barrels a day, that makes 1.8 litres for each human on Earth and thus over 7 litres per household per day.

Divided over 24 hours, the food eaten by a UK household corresponds to an average power of just under 0.35 kWatts. The same household is likely to run on about 2 kWatts worth of electricity and 10 kWatts worth of combustion heat to power central heating, hot showers/baths, kettles, toasters, ovens, computers, dishwashers, washing machines and tumble dryers… The few LED lights we’ve bought to make us feel better don’t change that overall picture. And that’s not including car driving, building materials such as steel, plastics and concrete, communal facilities like streets, hospitals, schools etc… all of which have an energy footprint as well. The truth is that a typical UK household is likely to consume 50-100 fold more energy for non-food processes compared to food.

There are several interesting take-home messages from this GCSE-style calculation. We consume an enormous amount of energy to be comfortable and this is at least an order of magnitude above our fair share if all the crude oil were to be distributed evenly. Secondly, whoever thinks that waste products of the food industry can produce meaningful quantities of bio-fuel to drive cars or to heat homes lives in a dream world.

As scientist I have been trained to be optimistic when I design experiments and I share this attitude when I think about the world and its occupants. Take for instance Brazil, a country that has spearheaded sustainable bio-ethanol production from sugar cane. When you confront Brazilians with the typical stereotype saying that they are destroying the rainforest to make biofuel you fairly merit harsh dismissal, and I would share this opinion too.

It may come as a surprise but still about 62% of Brazil’s total surface is still pure natural forest, only 33% is agricultural land and more than two thirds of the latter is pasture land. Sugar cane occupies less than 1% of Brazil’s surface and only half of this is used for bio-ethanol.

Moreover, Brazil produces approximately 20 billion litres of bio-ethanol per year, which is little compared to the 4,600 billion litres of crude oil produced worldwide. However, given the tiny surface currently used for sugar cane, Brazil could easily increase this figure, ideally at the expense of some pasture land. Allocating only a tiny portion of animal farm land worldwide to grow legumes and starch crops instead would go a long way towards feeding a growing population on Earth.

If you wanted to provide every human on Earth with 8000 kJoules of energy each day, just half a kilo of starch would fill that niche. Multiply this by 7 billion people and 365 days and you need 1,280 billion kilos of starch each year. A main crop potato yielding 50 tonnes per hectar in 5-6 months and a starch content of 20% could supply this on a land surface of just 128 million hectar or 1.28 million square kilometres, twice the size of France, or just a third of India.

But growing food is not enough, it also needs to be harvested, processed, packed, transported, refrigerated, dried, cooked… and all of this requires energy. In truth we should not consider “food versus fuel”, we should all think “food and fuel”. Is it therefore justified to condemn bio-fuel strategies in Europe just because sunflower bio-diesel or corn ethanol did not pass muster?

Potatoes and sweet potatoes are the most productive starch crops on earth, they can be integrated in annual crop rotation practices and they are harvested much easier than extracting oil by steam-injecting oil-sands in Canada. Most importantly, we can also eat them, offering an overall flexibility that is unmatched by lignocellulosic crops that have failed to yield any significant levels of bio-ethanol. Are we missing golden opportunities here?

I once stated at a conference that “food is more important than medicine, because everyone has to eat whilst only some people are ill”. One of the delegates argued that in the course of a lifetime everyone gets ill several times! I responded “and how often do you eat during a lifetime?” The truth is that medical research is funded by rich (and well fed) individuals, whilst the starving population of our planet is poor and cannot fund anything.