The Growing Importance of Desalination

A significant volume of water comes from desalination already. According to the data presented by the International Desalination Association, the cumulative contracted desalination capacity has now surpassed 100 million m3/d and nearly 60% of desalination is devoted to human consumption.

Water scarcity is a pressing issue affecting nearly 50% of the planet's population, who experience water shortfalls for at least a month each year. By 2025, 1.8 billion people are expected to face "absolute water scarcity."

To address this crisis, innovative solutions are needed, such as converting seawater into fresh water. One promising technology is an energy-efficient device inspired by the natural water cycle.

This device induces water evaporation, transports it to the surface, and condenses it in a closed cycle, preventing salt accumulation and enhancing device longevity. It uses renewable energy, running on solar power and converting 93% of the Sun's energy.

The efficiency is five times better than current desalination systems, producing 20 liters of fresh water per square meter, meeting the WHO's daily recommendation for basic drinking and hygiene.

The device's simplicity and portability make it suitable for remote regions, especially coastal and island nations.

Another portable desalination unit, developed by MIT researchers in 2022, weighs less than 10 kilograms and can operate with less power than a cell phone charger. It uses an electrical field to remove particles from drinking water instead of filters.

The unit combines ion concentration polarization and electrodialysis techniques, optimized using machine learning, and features a single button for automatic desalination and purification.

It can generate 0.3 liters of drinking water per hour, reducing suspended solids by at least a factor of 10 and meeting World Health Organization quality guidelines. Several companies are also engaged in large-scale desalination efforts.

Consolidated Water Co. Ltd. provides engineering services for the design-build of Sea Water Reverse Osmosis desalination systems, catering to the entire service cycle.

The company's technological preference is membrane separation, specifically reverse Osmosis, due to its lower energy costs. Consolidated Water operates several seawater reverse osmosis desalination plants in the Cayman Islands and the Bahamas.

In 2023, the company acquired full ownership of PERC Water Corporation, which designs, constructs, operates, and manages water infrastructure facilities in the Southwest U.S.

Veolia, another company, considers desalination a key solution to water scarcity and has built hundreds of desalination plants and systems worldwide.

The company's flagship projects include the Al Dur 2 plant in Bahrain, the Rabigh 3 plant in Saudi Arabia, and the Umm Al Quwain IWP plant in UAE.

Veolia's proprietary Barrel technology is a compact, digital RO desalination system designed for fast-track schedule and efficient remote monitoring.

In addition to direct desalination solutions, Veolia offers a combination of digital tools and expertise to optimize processes.

Currently, a significant volume of water is produced through desalination, with the cumulative contracted capacity surpassing 100 million m3/d. Nearly 60% of desalination is dedicated to human consumption.

According to estimates, about 300 million people rely on desalination for their daily water usage. Countries like Kuwait produce almost 100% of their freshwater use through desalination.

However, desalination projects are not yet distributed uniformly worldwide. The Middle East and North American regions together account for over 70% of the world's desalination capacity, with the Middle East alone contributing more than 53%.

Data indicates the presence of over 21,000 seawater desalination plants in 2022, collectively producing 99 million m3/day of desalinated water.

This production volume also results in over 150 million m3/day of brine byproduct, which is the slightly concentrated seawater rejected by the desalination plants to the sea.

The salt content of the brine is roughly 60g/l for seawater at 40g/l, while the temperature of the brine reject is slightly higher than that of the seawater – a few degrees Celsius.

Future research will need to focus on finding more environmentally friendly methods. The use of solar power in running these plants helps reduce the carbon footprint of these facilities significantly.

However, future research must ensure that nearly all the seawater input gets converted into fresh drinking water, leaving no harmful byproducts.

Efficient transportation and distribution mechanisms will ensure that this water goes beyond the nations located on the seashore and reaches arid, dry regions with no significant drinking water source nearby.