Understanding the Water-Energy-Food Nexus – Dr Anthony Turton
Floating in the lifeless infinity of the known universe, is one blue planet. It is the only place where known intelligent life exists. We call it Earth, even if it’s mostly covered in oceans. More importantly, it’s the only known planet where water is found in solid, liquid and gas form simultaneously. This is what we now believe to be the necessary recondition for biological life.
Not all biological life is intelligent, but the epitome of intelligence is Homo sapiens – Wise Man. That’s us. We have inhabited almost all known ecosystems on the planet, because of three simple factors that as a species, we have truly mastered. Without direct control over these three crucial elements, social stability would not be possible, and civilization would cease to exist as we know it today. These three factors form the great nexus of water, energy and food security. But, as the human population is growing, it is placing enormous pressure on that nexus, so let us unpack it to better understand what it is.
Average Diet: Requires 2,000 Liters of Water per Person per Day
Let us start with some basics. Our blue planet is made up mostly of water, with only 25% of the surface area not inundated. In fact, 97% of all water found on earth is saline. This means that only 3% is fresh. Of this total volume of freshwater, 70% is held in polar ice caps and glaciers. The rest is found in rivers, lakes, swamps and underground aquifers. Natural human population has outstripped that relatively small fraction of fresh water. Most of the dense clusters of human population are in lowlands, often competing for the best land where food is grown. According to the Food and Agriculture Organisation (FAO), 50% of all humans deal with shortfalls in water availability at least one month of any year. This trend is growing, and soon our species will have outstripped the total supply of fresh water at planetary level. This is more acutely evident in arid areas.
Each person needs about 2 liters of water each day to exist as a biological entity, but they need about 200 liters per day to live a hygienic life. It doesn’t stop there, because the global average food consumption is around 2,000 kcal per person per day. It takes about a kilogram of water to produce a calorie of food, depending on the diet. This means that the average person needs 2,000 liters of water per day just to sustain the food they eat. This is an important basic fact. Each person needs 2 liters of water per day to exist, 200 liters per day to be hygienic, and a whopping 2,000 liters for the food they eat. This order of magnitude relationship between humans and water lies at the heart of the nexus because we mostly think of water as the stuff we drink, but we seldom think of water embedded in the food we eat, or enabling the jobs we need to put food on the table.
Virtual Water and Food Security
Did you know that as much water enters the MENA region embedded in food each year as what flows down the Nile? This was the startling discovery of my mentor Prof Tony Allan, for which he was awarded the Stockholm Water Prize (the Nobel Prize for water). He called this Virtual Water, and it’s the reason why the wars of the next century will not be fought over water, as confidently predicted in the latter part of the 20th Century. Once we grasp this simple fact, we can begin to understand that food security is actually based on water security, but a water-constrained nation can still be food secure provided they can trade in food without being threatened with disruption.
We can now grasp the fact that most of the water needed for political stability in desert areas comes from grains produced on the prairies of North America, the pampas of South America, and the steppes of the former Soviet Union. This also means that future food security for the MENA region cannot be separated from water security. This suddenly opens the continent of Africa as one of strategic importance for the future security and stability of the Middle East.
The Energy Component
If water and food are intimately linked, then where does the energy component of the nexus come from? Again, we revert to basic numbers. In a coal-based economy, for every kilowatt hour of electricity that’s produced, about a kilogram of coal is burned, and around 1.5 kg of water is used. However, energy production also produces sulphur dioxide, along with carbon dioxide, both responsible for altering the pH of rain and therefore of soil. It is a well-documented fact that most soils contain aluminum, which is mobilized at a pH below 5. Aluminum toxicity reduces the yield of grains, so the production of food is directly linked with the production of energy.
This is what the nexus is all about. Soon national governments will be forced to make difficult choices about national water security, national food security and national energy security. In short, governments in water-constrained regions are directly confronted by the complexities associated with the water–energy–food nexus. Central to this overall process is the need to develop policy that incentivizes the transition from a linear economy (take, make, use, discard), to a circular economy. Those governments and corporations that understand these fundamental driving forces of change, will survive the consequences of this change, and go on to thrive after the turmoil of the transition.
This is what Nexus thinking is all about.
Dr Anthony Turton is the Head of Strategy at Nexus Resilience Group and a former Deputy Governor of the World Water Council. An authority on the notion of water as a national security issue, he holds a PhD in Hydropolitics and advised both Mikhail Gorbachev and US Secretary of Defense William Cohen on strategic water security at the end of the Cold War. He is a founder of the South African Water Chamber and African Water Issues Research Institute, and is the inventor of the nature-based “Wetland in a Box” water treatment system.
