Today’s Solutions: December 05, 2021

Water scarcity is one of the most challenging problems humanity faces. Water is floating in the air all around us and in our oceans, but despite having so much water on Earth, only a tiny fraction of it is actually drinkable — while the rest of it is either too salty, contaminated, or difficult to access.

To address this, a team of scientists at Caltech has developed a new system that can tap into two different sources to produce fresh drinking water — by purifying contaminated water during the day and collecting fog droplets during the night.

The key component of the technology involves a hydrogel membrane whose surface is etched with a particular pattern, containing an array of tiny hydrophilic structures modeled after the spines of cacti.

“Cacti are uniquely adapted to survive dry climates,” says Ye Shi, co-author of the study. “In our case, these spines, which we call ‘micro-trees,’ attract microscopic droplets of water that are suspended in the air, allowing them to slide down the base of the spine and coalesce with other droplets into relatively heavy drops that eventually converge into a reservoir of water that can be utilized.”

As explained by New Atlas, by placing a membrane of this hydrogel in a box, you virtually create a device that can collect pure drinking water. During the day, it absorbs heat from sunlight, which heats contaminated water underneath the membrane creating steam that’s then collected on a transparent cover and runs into a reservoir. At night, you can remove this cover to expose the membrane to fog from the outside.

In experiments, samples of the material ranging between 55 and 125 cm2(8.5 and 19.4 in2) generated about 125 ml (4.2 oz) of water from evaporation and about 35 ml (1.2 oz) from fog overnight. While that may not sound like much, the team says that the eventual daily yield could be up to 34 L (9 gallons) per m2 (10.8 ft2) of the material.

Original study: Nature Communications — All-day fresh water harvesting by microstructured hydrogel membranes

Solutions News Source Print this article
More of Today's Solutions

Need a mood boost? Consider drinking apple cider vinegar

Need a mood boost? Consider drinking apple cider vinegar Vinegar’s effect on mood A team of researchers from Arizona State University had already studied the positive effects of drinking red wine vinegar on blood sugar ... Read More

New Zealand is first nation to protect drug checking services by law

In a world-first, last week New Zealand’s government approved legislation made to protect drug checking, a service that saves lives by chemically testing illicit drugs to scan them for dangerous contaminants. The legislation is expected ... Read More

This all-female rainforest team is protecting India’s endangered flora

One of the most alarming effects of climate change is the toll it takes on global biodiversity. While these impacts are only expected to exacerbate over time if we don’t act with urgency, some natural ... Read More

Botswana decriminalizes homosexuality

Back in 2019, campaigners in Botswana fought to remove jail sentences for those caught in same-sex relationships, arguing that the punishment (which, since 1965, is up to seven years in prison) is unconstitutional. The country’s ... Read More

Bumblebees help solidify the link between microbiome and memory

The term 'microbiome' has been thrown around a lot over the past few years with many studies and health companies finding that a healthy gut balance can decrease your risk of cancer, clear up your ... Read More

Canada fast-tracks bill to ban conversion therapy

A bill that would ban the practice of conversion therapy in Canada has been unanimously adopted by the House of Commons, fast tracking it for approval by the Senate. Bill C-4 bans the practice of ... Read More