Gavin van Tonder
Water scarcity is becoming a major problem globally. And the question is, how do we resolve it? Recently I looked at how digitalizing water utilities can help, here the focus is on desalination.
Desalination as a viable solution for water scarcity has long been debated due to its energy-intensive processes and issues with brine as a byproduct. However, as the problem of water scarcity continues to advance alongside improvements to the process of desalination, we have to consider desalination as an option to tackle one of the most pressing issues we face today.
Below, I share my thoughts on:
- The growing challenges of water scarcity
- The issues surrounding desalination
- Advances in desalination
- Desalination success stories
Water scarcity — an expanding problem
Water scarcity has been a major topic in the world for years. However, we are now at the point where the demand for fresh water is so high that it’s outstripping supply. This has caused and will continue to cause major issues around the world, especially in built-up areas that face issues with getting fresh water or with its distribution.
Additionally, as we take fresh water from the resources that we have, we are also polluting it, only to put the polluted freshwater back into the same, scarce resources. Processing this wastewater and reutilizing it would go a long way toward reducing water scarcity.
However, there are certain areas of the world like the Middle East, Australia, and some places in South America that are extremely arid where people face difficulties in accessing fresh water.
Issues with desalination
Desalination is one solution that could address the water scarcity issue. Since 70% of the world’s surface is seawater, we have an enormous amount of water available — yet this water is not of drinkable quality.
The question is, then, is desalination a viable solution to reducing water scarcity and supplying populations with fresh, drinkable water? This has been asked many times over many years. Issues surrounding desalination include high costs — it’s much cheaper to take water from a river, dam, or aquifer, and it’s also an energy-intensive process.
We also have a responsibility to protect marine life, yet chemicals and minerals are added to the water during the desalination process which is then put back into the ocean. A very large amount of brine — essentially concentrated salts — is produced and put back, too. While there is an argument that this has no impact on the sea, it’s been proven that the salinity of the Arabian Sea has increased by 10%, and in other locations by 20% because the sea is so shallow.
Putting brine back into the sea has a material impact on the environment, which is an issue — along with the costs, energy, and CO2 produced — that needs to be resolved in the long term if desalination is the solution to water scarcity.
Advances in desalination
Desalination has come a long way over the last ten years. Originally, evaporation and evaporating water with very low recoveries and putting the brine back into the sea was costly and pumped a lot of CO2 into the air.
However, since the invention of reverse osmosis, this has decreased expended energy dramatically. The amount of CO2 released into the air and improved recovery rates have led to less seawater coming out of the sea, and in turn, to a large decrease in the cost of desalination — what once cost $1 per meter cubed is now half a dollar per meter cubed, and less in some cases.
These improvements, as well as the advent of renewable energy through solar and wind, have optimized desalination over the last five years for it to be considered — from a cost perspective — a very viable solution to reducing water scarcity.
Connecting reverse osmosis with desalination facilities enables us to further reduce costs. More importantly, this has also enabled us to reduce the CO2 that’s released into the air more cost-effectively.
However, the issue of putting brine back into the sea, causing damage to sea life, and altering the marine environment, still remains. One solution to counteract this is to not put the brine back into the sea, or, to put it back in a better condition than when it was taken. If this were to happen, desalination would be a very positive solution to the problem of water scarcity.
Desalination success stories
Some areas in the world, such as the Middle East and Australia have advanced their journey with desalination. For example, much of the desalination that occurs in Australia is offset by renewable energy — this is also occurring in some regions of the Middle East, Saudia Arabia, and the United Arab Emirates. Some of these desalination plants are also being connected to solar facilities that can generate a lot of power, which reduces the need to take water out of aquifers and enables groundwater levels to rise.
In NEOM (a city being built in Saudi Arabia which will incorporate smart city technologies), zero liquid discharge is being used to protect the sensitive marine environment, including coral reefs. NEOM is also utilizing renewable energy, which offsets the issues surrounding desalination.
When we take all of this into consideration, it’s clear that desalination is going a long way toward solving the world’s water crisis.
Qatium Experts
Gavin Van Tonder is the Executive Director of Water at NEOM and is one of many experts that we co-create Qatium with.
