Company creates a unique system to turn saltwater into drinkable water using a solar-powered thermal desalination

In 2010, William Janssen, a Dutch mechanical engineer and product manager, was overseeing construction of the Ferrari World theme park in Abu Dhabi, a country facing severe water scarcity. While he was there, he suddenly had a eureka moment unconnected to rollercoasters or sports cars. Rather, it was about water.

“I had taken note, in the Mediterranean area and other countries, that people have solar heaters on their roof to create hot water—basically a solar collector with a tank above it,” William recalls. “To go one step further and make boiling water would also be possible.” He realised that the steam from boiling saline water could be turned into distilled water, remineralised, and drinkable.

He was surprised to find that there were no existing patents for his idea. He conducted a proof of principle and saw that he could harvest pure water from saltwater using only the sun.

In 2013, he filed his first patent. Later that year he created a company, Desolenator, which proposes the world’s first circular, solar-powered thermal desalination system.

The technology will work anywhere on the planet where there is ample sunshine—in other words, between the two tropics, from the Mediterranean to South Africa, the southern United States to Northern Chile, and Southeast Asia to Australia. These also happen to be the places where the water shortage is most pronounced.

Addressing water scarcity worldwide

Fresh water accounts for only around one percent of the water on the planet. This precious supply is under increasing stress due to a range of factors, such as population growth, urbanisation in coastal areas, desertification, and overuse of existing water aquifers and reservoirs.

The water crisis has often been overlooked by the climate movement. William says that as early as 2030, two-thirds of the global population will experience a situation of water stress annually. “That’s less than seven years away. It’s a shocking situation. Billions of people will be struggling for water every year.”

Even if societies improve rainwater harvesting, reuse their wastewater, and build better reservoirs, desalination will still be necessary to meet the upcoming water shortage. But traditional desalination, using reverse osmosis, is extremely polluting and has developed a bad rap. It requires fossil fuels and chemicals, creates CO2 emissions, and discharges toxic brine back into the ocean.

“I could go on a fishing boat in the middle of the Arabian Gulf, take a sample, and send it to a lab in Poughkeepsie [New York], and they would say this is water from the Arabian Gulf because it contains chemicals XY and Z,” William notes.

In 2016, Desolenator won second prize in the EU’s Climate Launchpad competition, as well a becoming a finalist in the European Investment Bank Institute’s Social Innovation Tournament, which recognises entrepreneurs making a social, ethical, or environmental contribution to society.

A sustainable desalination process

William says that Desolenator’s technology reduces carbon emissions by 1,400% as compared to reverse osmosis. It separates salt from water through evaporation, for a low concentration of non-toxic brine, or even zero liquid discharge, eliminating brine by producing salt. Interestingly, this salt can be mined, using a process called nano-filtration, to obtain minerals—calcium, magnesium, sodium, chloride, and even lithium.

Desolenator now has three patents, employing existing technologies and off-the-shelf parts. Its plants operate around the clock, independent of the electricity grid. Buffering allows the technology to work even when the sun doesn’t shine—thermal batteries are charged during the day and discharged at night. In case of power outages the system uses lithium-ion batteries as a backup.

Jo Burgess, Head of Trial Reservoirs at Isle Utilities, an international consultancy in water industry transformation, has written, "Arguably one of the most exciting technologies I've seen in recent times (and I’ve seen hundreds), watch Desolenator carefully because they are going places."

Expanding to agricultural irrigation

The Middle East, where William first had his idea, is Desolenator’s beachhead market.

Four years ago, Desolenator signed its first contract with the Dubai Electricity and Water Authority and delivered the plant one year later.

Now, the startup signed its second contract, for agricultural irrigation water, with Silal, a company in Abu Dhabi. Silal calls Delosenator’s technology a “paradigm shift in handling the vital water-food-energy nexus.”

William says that his solution is cost-competitive, so large corporations generally have no problem investing in a plant. Moreover, they have good reason to do so, as water scarcity puts billions of dollars’ worth of business assets at risk.

On the other hand, smaller companies and municipalities might struggle with the initial investment in Desolenator technology. In that case, Desolenator can install, operate, and finance a plant, which includes a solar array. The customer receives a monthly bill for water use, and after 15 years owns the plant.   

Humanity has long taken water for granted, but that is starting to change. By harnessing the sun’s power, Desolenator is helping to ensure access to fresh water without spill over into the environment at large.