With the world population growing at a rate of around 80 million people a year, it is estimated that by 2030 the world will need 30% more water, 40% more energy and 50% more food. That’s not just to feed, water and power the new arrivals, but also those currently living “off grid” in developing countries as they rise out of poverty.
In the past, water, food and energy have too often been dealt with as separate issues. Biofuels are a classic example. Once the great hope for sustainable energy, bio-diesel’s insatiable appetite for wheat saw global food prices spike in 2008 and 2011, causing civil unrest. Panicked into action, the international community spoke out at the German government’s Bonn 2011 conference and the water-food-energy nexus.
What is nexus thinking?
The nexus is a recognition that any solution for one problem, for example water, must equally consider the other two in the nexus. Jeff Erikson, senior vice president at environmental consultancy SustainAbility, explains: “Water is required all the way through the lifecycle of electricity and power generation, from fuel extraction to production; electricity is required to move and process water, while agriculture accounts for 70% of the freshwater consumption worldwide. One is dependent on the other, and the demand for all three is going to continue to grow.
“Then you put climate change on top of that, which is going to have a significant impact on both agriculture and water availability, and you can see how things will continue to get squeezed over the next number of decades.”
From the World Economic Forum in Davos, Jon Williams, partner, sustainability and climate change at PricewaterhouseCoopers (PwC), says unsustainable resource consumption can only get worse without the nexus. “Water is pretty much used for everything that we do and is already becoming scarce in large parts of the world; the more energy we use, the more water we need to cool power stations … [And] If the whole world ate like Europeans or Americans there would be no way there would be sufficient food, let alone the water to grow it. The three competing pressures [water, food, energy are] pulling in completely the wrong direction at the moment.”
China as a case study
China is an interesting case study. Professor Declan Conway of the UEA Water Security Research Centre has extensively researched water and energy use in the world’s most populous country: “Many of the pressures we’re talking about globally are all occurring within China,” Conway says.
“It is the world’s second largest irrigator, using a huge quantity of water for growing of crops, much of which is pumped from underground – and that requires a lot of energy. We recently found that 0.5% of China’s total emissions come simply from the pumping of groundwater for irrigation.”
Potential responses to these issues are still in their infancy, but China’s next five year plan includes planning goals for energy efficiency and emissions, food production and water use, including “how much water goes into growing a particular crop,” says Conway. “A lot of effort has gone into softening the blow on agriculture while incentivising much more efficient use of water.”
But these are not strident solutions. China is currently pumping water out of the ground at a rate of 20 cubic kilometres per year faster than nature can replenish. Worse still is the US at 30 cubic kilometres, and India at 190 cubic kilometres.
Policy has yet to catch up with the rhetoric of international conferences, argues Jeremy Allouche, research fellow at the Institute of Development Studies. “The problem with the nexus at the moment is it hasn’t led to any policy concepts … and it hasn’t led to key players taking it forward,” he says.
Aligning policy with action
There is a perverse positive: our current usage of water, food and energy is so outrageously inefficient that improvements are not hard to find. “The sad fact is that anywhere between 10-15% of the food we produce ends up in waste,” says Williams, who in part blames agricultural subsidies. “It’s quite scandalous that a society produces more food than it can actually reasonably eat. Equally, he continues, “if you look at individual buildings there are examples of 25-75% reductions in energy use by simply insulating.”
When domestic and industrial use of freshwater only account for 8% and 22% accordingly, compared to 70% by agriculture, it may seem that individuals and business are relatively powerless. However, not according to the nexus. “The energy associated with other uses of water can be quite high”, says Conway.
“The need to pump and deliver water and to treat it to drinking water standards, can be far higher than the energy requirements associated with agriculture. So although the volumes are different, the energy use can be much higher per unit of water.”
Meanwhile, biofuels may be set to make a comeback. Jesper Hedal Kløverpris is sustainability manager at Danish biotech company Novozymes, producer of the enzymes needed to make cellulosic ethanol. “What’s interesting in relation to the food-water nexus is we make cellulosic ethanol simply by taking the residues – or waste – from the existing agricultural system,” says Kløverpris. “It has a big potential for producing energy without additional agricultural water use.”
In theory, while ears of corn are harvested for food – and previously for bio-ethanol – only waste stems are needed by bioethanol refineries, hungry for the cellulose and hemicellulose normally discarded, rather than the starch and protein. Large bioethanol refineries have already appeared in Italy, Brazil, the US and China. Research by Bloomberg New Energy Finance found that by 2030, this has the potential to replace more than 50% of gasoline consumption in some countries. “That gives an indication of the potential”, says Kløverpris. And as for the water intensity of bio-refineries and the greenhouse gases emitted by the process, he admits the “science is still progressing”, but cites recent studies that have found in favour of cellulosic ethanol versus gasoline.
One thing the nexus highlights is that an awful lot needs to be done in the next two decades and an awful lot faster than it currently is happening.
“We are profiling the need to make these linkages much more than we were”, says Conway. “Whether we are making a lot of progress in actually getting there and making those linkages, I’m less sure … We’re still on a trajectory of rapid change that has huge implications for consumption patterns, energy use, the land needed to provide crops.”
It’s time for nexus thinking to make way for nexus action.
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