Open any newspaper or website, and news of our impending doom at the hands of global warming is likely to slap you in the face. Humans are, of course, notoriously bad at seeing the signs and being proactive. Recent natural disasters in many parts of the world have, once again, brought the issue of climate change to the forefront. For now, we seem interested in saving the planet again.
Locally, the Western Cape has been experiencing the worst drought in a century, leaving many mourning the death of their plants and the steady accumulation of grime on their cars. Water restrictions have reached an unprecedented level 5, with both residential and commercial property owners facing the daily struggle of lowering water consumption levels.
On a global scale, places like the United States have long experienced crippling droughts in, among other places, California, while the UAE face clear struggles in building livable and sustainable cities in a desert. The question many are asking is: How do they do it?
The first part of that answer is clear: money. Recent announcements by local government regarding plans to tackle water shortages included desalination plants, boreholes, and upgrades to dams. These amount to an estimated R2 billion in expenditure in 2017/18, while operating expenses would amount to at least R1.3 billion. As with anything, this would also mean tariff increases over the next few years. While these plans are much-needed, and according to some much-overdue, it doesn’t do much to alleviate immediate fears over access to water.
One solution, oftentimes unfamiliar to everyday consumers, is the Atmospheric Water Generator (or AWG). According to David Fulton, Director of Aquaosmo in South Africa, AWG technology will play a major role in ensuring citizens have access to clean drinking water – regardless of failing municipal infrastructure or drought. Kevin Winter, a lecturer in Environmental and Geographical Sciences at the University of Cape Town, emphasises the need for new ways of thinking, explaining that: “we shouldn’t see the current water crisis as a temporary phenomenon that will resolve in a year or two. It’s a long-term problem. We will need substantial government intervention to make Cape Town’s water supply sustainable.”
How does an Atmospheric Water Generator Work?
- Fresh air enters the machine through air filters
- Filtered air is cooled down to its dew point
- Condensation forms water and falls into the reservoir tank
- Water is pumped through filters
- Water undergoes reverse osmosis procedure
- Water is pumped through mineralisers up to top reservoir tank
- Pure water is stored in top reservoir tank and UV treated
Fulton explains that, while the start-up cost of an AWG may be daunting, the price per liter of water is surprisingly low: “compared to bottled water, the price for a 20l unit would work out approximately R1.94/l, including the capital cost, electricity, and service agreement. Compare this to bottled water, coming in at around R5.75/l.”
Depending on application, machines range from 20l/day capacity to 20 000l/day. Models larger than 250l/day require three-phase electricity supply, leading to specialised and customized installation. The units can also be linked to external water tanks, allowing it to work at full capacity even when the built-in tank is full.
In times of critical water shortage, the taste and quality of municipal water is oftentimes compromised, prompting many consumers to install water filters – or to resort to bottled water. The AWG, Fulton explains, produces cleaner water, free of chlorine or other chemicals. In addition to this, the water is constantly being filtered within the machine, avoiding the possible build-up of bacteria found in stagnant water.
AWG technology works in areas with humidity as low as 30%, with efficiency levels logically rising along with humidity levels. The efficiency of the machine is also impacted by the state of the filter, with a new one being recommended between 6 and 12 months after purchase; this, of course, is dependent on the amount of dirt in the air.
The recently-announced level 5 water restrictions require commercial buildings (including offices) to reduce water usage by 20%,contributing to already-tight budgets and operating costs. While large offices are the most obvious recipients of an AWG machine, any office or household stands to benefit.
Fulton explains that they offer cash purchase or rent-to-own options:
20l/day: R495/month (R16 750)
40l/day: R575/month (R19 750)
100l/day: R1 550/month (R58 500)
250l/day: R2 550/month (R115 450)
In terms of sustainability, it’s helpful to consider utilizing solar power – thus allowing you to move off the grid completely. Again emphasizing the need to think proactively, Winter states: “This is a global system, so the bigger systems are beginning to impact us, so there is no doubt that pressure and temperature are related. So disturb the temperature, you disturb the pressure and you start to see different systems operating.”
Sources: Aquaosmo South Africa