Jacques Cousteau paved the way for long-term underwater exploration. His innumerable dives and hours upon hours of documentary footage are just some of what he’s been up to lately.  He once spent 30 days living beneath the Red Sea; his grandson, Fabien, one-upped his grandfather by staying below from June 1 to July 2 in 2014–a solid month of submersion. But how much longer might future explorers go if they weren’t reliant on air supplied from the surface, but rather harvested directly from the water around them?

Thanks to efforts of one diver turned engineer motivated by a surprising science-fiction source, divers are one step closer to filling their tanks straight from the sea itself.

It is a matter of elementary-school science that water is made up of two parts hydrogen and one part oxygen. Unfortunately, it’s equally fundamental that, even if you could split those molecules apart without electrocuting yourself, humans have to leverage their oxygen intake with plenty of nitrogen.

Efforts to breathe underwater focus on the tiny amounts of air dissolved directly into seawater. The percentage of breathable gases in water is minute—less than 2 percent, of which the majority is nitrogen (approximately 63%) and oxygen (approximately 34%) at equilibrium with air, which contains more nitrogen (78%) and lesson oxygen (approximately 21%) by volume. Moreover, these ratios are fine for fish, but warm-blooded mammals require 20 times more energy in order to derive breathable gas.

There have been several false starts in the path to splitting the water molecule. The Aquaman Crystal made headlines with it its promise of enabling divers to take in oxygen directly from the water by using special crystalline cobalt salts to derive oxygen directly from the water. Unfortunately, as Motherboard reported in 2014, it would require untenable amounts of the salts to keep a human breather oxygenated.

In 2014, Korean design student Jeabyun Yeon claimed he had built a device that drew air directly from the water via a mesh with submolecular-sized holes. Dubbed “Triton” after Sean Connery’s “rebreather” in the James Bond flick Thunderball, Yeon earned several headline stories for his device (in addition to crowdfunding $700,000 on IndieGoGo), but the device’s serious scientific shortcomings became increasingly apparent (not to mention any concrete evidence that that device existed). At the time of reporting, Triton’s IndieGoGo page had been shut down.

So far, the most promise in the field has come from Alan Bodner, whose company,Like-A-Fish Technologies, began pursuing a process to liberate dissolved air from seawater 15 years ago—inspired by, according to The Daily Planet’s feature on Bodner’s project, his son’s inquiry as to whether Qui-Gon Jinn’s A99 aquata breather inThe Phantom Menace was really possible.

Bodner’s invention relies on reaeration—re-separating the miniscule amounts of air dissolved into water and pumping it to the breather. Bodner hypothesized that, by applying Henry’s Law to seawater, the dissolved air would separate from the water, the way that carbon dioxide fizzes out of a shaken-up soda can. To achieve this depressurization, Bodner’s device pumps the water through 8 meters (24 feet) of narrow tubing. Thus deflated, the water enters a centrifuge, which spins heavy particles (water) to the sides of the centrifuge and leaving lighter particles (air) at in the center.

An engineer and a diver, Bodner initially set out to create a single tank that could be fitted onto a wetsuit.

His plan ran up against the energy demands necessary to power the reaeration process, however—the technology simply isn’t yet in place for a battery to filter one liter of air 200 gallons of water in a single minute. And so, just as Cousteau occasionally swapped his scuba gear for the confines of the SP-350 Denise, Bodner currently focuses on an Italian-made aquamarine submersible as the vehicle for Like-A-Fish’s technology.

In 2015, Like-A-Fish partnered with iNova, a start-up founded in 2013 to research clean energy projects geared towards marine transportation and available not only to well-funded underwater explorers, but also to the average person.

As told by the company’s founder and CEO, Giuseppe Carusi, “theAtlantis is a futuristic, multipurpose over and underwater travel vehicle, designed and built for leisure, research or public utility purposes.”

According to the iNova press release,

“The Atlantis is the first submarine to be equipped with the ‘Like-a-Fish’ patented technology, a new system which can extract breathable air directly from the water during travel.This is why we call it “The Submarine with Gills.”

The current Atlantis model is designed for one pilot and up to three passengers. Its lithium-ion batteries are designed to power both the reaerator and the twin 40-horsepower electrical engines to propel the vehicle through the deep.

The Denise could stay submerged for four to five hours. If the Carusi and Bodner’sAtlantis can keep its crew breathing indefinitely on air taken directly from the waters it explores, there’s no telling how much further the explorations could go.

Image Credit:
Article via