Wednesday, 26 January 2011

To feed eight billion people in 2030, we need to remember our food system is linked to our energy use

Spraying slurry on tea, Soc Son ProvinceThree reports have appeared in the last fortnight highlighting the urgent need to address the food, energy and water demands of a population that's expected to reach eight billion by 2030. The report, One Planet, Too Many People?, from the Institute of Mechanical Engineers, looks at the pressures of population growth on our food, energy and water systems. The report, State of the World 2011: Innovations that Nourish the Planet, from the World Watch Institute, explores sustainable solutions to our food system. The Foresight Project's Global Food and Farming Futures report examines how we can meet the food needs of our planet in the next 20-40 years.

Mike Pepler, our UK Awards Manager, emphasises the theme that's emerging from each of these studies: the challenge of how to feed the world in 20 years' time must be done in combination with meeting rapidly rising energy demands. We must address our need for a productive food system at the same time as reducing our dependence on fossil fuels.

A good example of the energy input that goes into agriculture is fertilisers. Our intensive use of fertilisers produces a double whammy of greenhouse gases. Mike says:

"Nitrogen is a key element needed for plants to grow, but it has to be incorporated in chemicals that plants can use. There are natural processes that achieve this, but the nitrogen added through man-made fertilisers has doubled the amount available for plants to grow. CO2 is released as a result of the Haber-Bosch process which is used to produce ammonia to make fertiliser. Then the fertiliser, once spread on the field, also emits nitrous oxide - this is the third most significant greenhouse gas, after CO2 and methane."

"About 3-5% of the world's natural gas supply is used to produce nitrogen-based fertiliser - that is about 1-2% of all energy use globally. Although the advent of petro-based chemical fertilisers in agriculture is one of the pillars of the 'Green Revolution' that boosted food production in the latter half of the twentieth century, it has come at the cost of increased greenhouse gas emissions".

"The climate change caused by greenhouse gases, including those emitted by fertilisers, is now threatening food production, and will become more of a problem as time goes on. We must recognise the link between sustainable energy systems and our agricultural system. More research is needed on this topic."

See also: Three steps that each of us can take to help.

(Pic: Farmer in Vietnam uses slurry from biogas production as a natural fertilizer for their crops)

No comments: