Friday, 28 June 2013

Feeding the World: The Challenge of Energy for Food Security

This article by Helena Wright, Imperial College London is part of the Wikiprogress Environment Series.
Back in 2008, business leaders at the World Economic Forum raised a call for awareness of the nexus between water, food and energy security, as well as climate change.  They realised that there is a serious water crisis ahead, as many groundwater resources are depleted, while demand for food and energy is increasing.  By 2030, the world’s population and economic growth are expected to lead to a 40% increase in energy and water demand, and a 50% increase in food demand.  Meanwhile, climate change puts additional strain on agriculture.
Energy is crucial for production and transport of food, from the ‘farm to fork’.  The Food and Agricultural Organisation (FAO) of the UN estimates the food sector currently accounts for around 30% of the world’s total energy consumption and over 20% of greenhouse gas emissions.
As illustrated in the graph below, the increases in food prices of recent years have been closely linked to rising energy and oil prices, with serious economic implications. The poor are particularly affected by high food prices as they spend a high proportion of income on food. Worryingly, the triple food, fuel and financial crisis of recent years may be a taste of things to come.
Global agriculture is highly dependent on energy from fossil fuel-burning for many processes, from on-farm mechanisation, to fertiliser production, to food processing and transportation. The price of oil is also closely correlated with the price of fertiliser.
The emerging biofuel market increases interdependencies between food and energy prices, since feed and fodder commodities are being used for biofuel, and also because a higher oil price increases demand for biofuel. The Stockholm Environment Institute (SEI) has found that growing bio-fuels from crops is extremely water-intensive, as well as being a practice which puts pressure on food crops.  According to the FAO, it takes 2,500 litres of water to produce one litre of biofuel for transportation. New legislation may be needed to address the impact of biofuel mandates on food and water security.
Energy and water are both absolutely essential for food.  This is especially true because irrigation is used for the production of roughly 40% of global food.  In this way, agriculture accounts for about 70% of all freshwater withdrawal.  Inefficiency in one area can also lead to inefficiency in another. For example, subsidised electricity for irrigation can lead to over-pumping, which contributes to groundwater depletion. Where water is extremely scarce, desalination – which is highly energy-intensive – is used.
As conventional fossil-fuel sources become depleted, we have seen a shift to processes like hydraulic fracturing (“fracking”) which are even more water-intensive.  Extraction and processing of oil sands uses about 100-1000 litres of water per gigajoule (GJ), compared to 10-100 litres for conventional oil and gas. According to the World Resources Institute (WRI), 79% of new planned power capacity in India will be built in water-stressed areas. Use of Carbon Capture and Storage (CCS) technology also increases water consumption.
Renewable energy has brought new challenges.  Hydropower, already the world’s dominant source of renewable energy, is a prime example of a technology that must be carefully managed to avoid negative impacts.   Dams can affect biodiversity, fish migration and have impacts on downstream food security.  It is clear we must start to think about the ‘water productivity’ of energy.  Solar power, for example, hardly uses any water.
In the long-term, it will be necessary for our food to be produced using sustainable energy resources and this is likely to require a transformation in agricultural systems.  At the moment, we are seeing the opposite occur: food crops such as maize and soy are being used to fuel energy-consuming transport. This issue must be tackled. Otherwise, there is a risk food prices will continue to sky-rocket.
Research is only just beginning to explore the complex issues in the food-energy-water nexus. What is clear is that better collaboration is needed between different sectors. Policy-makers must ensure that expansion of certain types of energy does not put a strain on other vital resources.
At the UN climate talks in Doha last month, it was evident that policy-makers often work in silos – for instance, there can be little cooperation between those working on reducing emissions and those on adapting to climate change.  This may have led to the controversial issues created by biofuel expansion.   It is clear a more holistic outlook is needed in tackling these problems and managing increasing demands for energy, water and food.

This article first appeared in the Outreach Magazine 

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