As the 21st century unfolds, we as a global community are called evermore to be stewards of our shared environmental resources. Part of that responsibility finding and effectively implementing new ways of producing cleaner energy, while being conscious of what the impact of our production is.
When we use alternatives to carbon-intensive fuels, it allows for natural resources to be rejuvenated for the ecological benefit and creates a more sustainable balance. Our understanding of the best practices for managing raw resources and the means by which we use them is rapidly growing. Relationships between resource and consumer can be bewilderingly complicated, but emerging technologies that shorten the gap between consumer and production are a step in the right direction.
These kinds of technologies are especially interesting because of the far-reaching implications of their application. Not only do they reduce emissions, but they also free up other resources. Exciting developments are coming in every sector, and one of the more promising examples tackles a worthwhile goal: solar desalination to make clean water on a large scale.
How to Make Water
It is actually possible to create water through chemistry. But the main ingredients, hydrogen and oxygen being extremely flammable, make creating water on any type of useful scale quite impractical. Fortunately, though Earth’s supplies of fresh water are limited to certain geographic areas, there is an inexhaustible supply of saltwater.
Desalination is the process of removing salt from water. It’s a concept that’s been much experimented with, and there are numerous processes such as reverse osmosis that show promise in efficiently removing impurities from water. The most basic way to do it is with solar distillation.
Solar distillation isn’t a new process, people have harvested water through these means for nearly a millennium. The basic idea is pretty simple, you need only heat saltwater with heat or energy generated by the sun until it begins to evaporate, collecting and condensing vapor. This process is an effective means of removing salt from water, and effectively removes minerals and other impurities as well. Unfortunately, even modern solar stills aren’t efficient enough to be industrially practical.
This inefficiency is a common critique of desalination efforts as a whole. The various processes through which water can be purified need to be powered somehow, and the amount of fuel consumed is disproportionate to the amount of water they produce. But, improvements in the efficiency of solar technology could drive these processes and effectively remove the need for the complicated relationship between water production and energy consumption.
The Relationship Between Water and Energy
Energy production and potable water reserves are intimately linked. One need look no further than the extensive damming of the western United States to know that. Historically production of either water or energy requires large amounts of the other.
In places where desalination efforts are employed, the water table is usually stressed and the area often desertified. Harvesting water in this way is demanding, using heat energy derived from burning petroleum products. These petroleum products, in turn, require water during the processes of extraction and refining. It’s something of a vicious circle.
Producing water consumes energy, and producing energy consumes water. In addition to this, carbon emissions from energy production contribute to factors such as ocean acidification in saltwater, and contamination of freshwater stores necessitating their purification and thus more wasteful water and energy consumption. But, promising developments combining solar cells with innovative desalination processes can provide access to fresh water on local and industrial scales.
And as the fastest-growing source of energy, new solar technologies are also making it both cheaper and more efficient.
The technology to purify water by solar energy is a few thousand years old, and making your own solar still at home is easy to do. But because solar distillation is an inefficient way of heating mass quantities of water, we can instead use the sun’s energy to power machines that have.
By using solar thermal energy to drive reverse osmosis desalination efforts and other mass capacity desalination processes, we can disentangle water supplies from carbon emissions. Not only does this reduce the industrial production of greenhouse gases but water that was used in the extraction, refining, and transportation of that fuel is freed up for other purposes. We have the blueprint for a virtuous circle.
It’s a magnifying process, learning to rely on renewable energy and employing it strategically in resource-heavy industries has a cascading effect. In water-scarce regions, the implications of this are ecologically huge.
Fighting for the Future
As we see the global ecological effects of industrialization play out, it’s anticipated that a significant amount of the world’s population will be affected by water scarcity, a jump to 14% within the next decade. It’s also worth noting that human health is closely related to the quality of our water. Prioritizing equitable access to freshwater and conserving existing freshwater resources is tremendously important.
What is possible with solar power and desalination is just one of the many examples of the ways that green energy can be used to reshape systems of public and environmental life in widespread, tangible ways. By investigating and pursuing these technologies while always striving for greater efficiency, we can learn how to model change. Similar technology across any number of industries could hold just as many impactful and unexpected benefits.
Casper Ohm is the editor-in-chief at Water-Pollution.org.uk, an outlet intended to raise awareness of the alarming levels of water pollution in our planet’s oceans. When he isn’t scuba diving and collecting data in the far corners of the world, he lives in New York with his family.