– Solar technology could increase global access to drinking water
While water covers two-thirds of the Earth, 96.5% of it is in the oceans. Desalination processes can refine this salt water into something drinkable, but past systems have posed a number of problems. Recently, however, researchers have developed ways to desalinate seawater using solar energy.
How solar desalination works
There are different approaches to solar desalination, each using sunlight at a different stage in the process. Researchers at Monash University in Australia have developed a system that uses a metal-organic structure (MOF) to filter out salt and other impurities. The MOF adsorbs impurities in 30 minutes, then the sunlight removes the adsorbed particles from the MOF.
A recent invention from the Korea Institute of Science and Technology works differently. This desalination approach uses sunlight to evaporate seawater, pass it through a hydrophobic membrane which filters the salt. When this vapor cools, it condenses back to liquid form in the form of clean drinking water.
These solar desalination techniques can produce hundreds of liters of drinking water per day. Since they are dependent on solar energy, they are also energy efficient, which helps them solve water scarcity and sustainability issues.
Problems with previous desalination techniques
Obtaining potable water by desalination is far from being a new process. Ancient cultures boiled seawater to remove impurities, and large-scale thermal desalination has exists since the 30s, but has always been ineffective. Although these desalination processes are efficient, they tend to consume large amounts of energy.
Generating enough heat to evaporate water on a large scale requires a substantial amount of energy. Since most of the electricity comes from fossil fuels, these large desalination plants often contribute a considerable amount of carbon emissions. As the climate crisis becomes more urgent, this level of energy consumption is unsustainable.
Solar desalination occurs on a smaller scale than other techniques, but it is much more efficient. The Australian and Korean approaches both use less energy than even reverse osmosis, which itself is more than twice as efficient as traditional thermal distillation.
The need for sustainable water purification
Solar desalination could be the answer to one of the world’s most pressing problems: water scarcity. Although there is enough fresh water on Earth to serve the entire population, about 20% of humans have limited access to it, with industries like agriculture and food manufacturing contributing to pollution of the world. water and now looking for more sustainable ways to provide food and water to the world. This means that more than a billion people struggle to obtain clean drinking water, a necessary resource.
The world’s oceans can provide more than enough water to meet global needs if people can desalinate it. As natural sources of fresh water become scarce and populations proliferate, this source becomes even more attractive. Solar desalination techniques would allow water-poor communities to benefit from this water without sacrificing energy efficiency.
Roughly 40% of the world’s population lives near a coastline, making desalination a relevant option for over 2 billion people. If solar desalination could reach this scale, it could make water scarcity a thing of the past. Even if it does not serve the entire population, managing this quantity would make it possible to reserve enough water to meet global needs.
Solar technology is crucial to preserve the Earth
Maintaining current global levels of use will require expanding access to safe drinking water. At the same time, turning to high energy processes can lead to environmental problems with carbon emissions, negating any positive effects. Solar technology is two sides of the equation.
Solar desalination techniques are still in their infancy, but the first results seem promising. By turning to sustainable methods like this, the world can ensure that everyone can access clean water and save the environment.