Pure hydrogen can be produced from water using solar power

An electrolyzer “can produce more than 99.9 percent pure hydrogen from water, while running directly on solar power, for under $2 per kilogram—roughly the cost level the US Department of Energy targeted for 2026. Terraform’s goal is to eventually combine hydrogen with carbon dioxide captured from the air to produce synthetic fuels,” reports The Doomslayer.

The electrolyzer is from Terraform industries. Its physicist Casey Handmer says,

Last week the hydrogen electrolyzer team pulled off yet another first, the sustained production of 99.9% pure H2 from our vertically integrated, California-manufactured electrolyzer stack while it was coupled directly to a solar array at our Muroc desert test site….Most commercial electrolyzers need carefully conditioned power from expensive battery-meditated backup systems. Ours runs directly off the sun…from a stack whose cost is well below $100/kW. Terraform’s single-minded focus has allowed us to convert sunlight to hydrogen in an unprecedented demo at a cost below $2/kg [which experts said was impossible]. If that wasn’t enough, we have a crystal clear plan to push that cost below $1/kg in the coming years…Much of the test prep was completed before dawn, when the panels go live. The sun came up and the stack immediately started splitting water into hydrogen and oxygen. The team carefully monitored purity and flammability as the sun climbed through the sky. As designed, the stack warmed up and conducted even more power, maintaining solid production until late afternoon when the setting sun shaded the panels.

Terraform’s synthetic fuel system is uniquely designed to follow the sun and extract the maximum possible value from cheap solar panels. Hydrogen is a pernicious molecule. It leaks through and embrittles metals, burns almost invisibly at a wide range of mixtures in air, burns hot and fast and can easily undergo detonation transition, and has about half a dozen other spookily dangerous properties….

The Terraformer produces and consumes H2 in one compact discrete area with a minimum of complexity and fuss…This successful demonstration was also a profound milestone for the team after a testing anomaly last December compelled us to finally rip off the bandaid and move decisively towards the “future design” with half the parts but considerable complexity in assembly. No-one else makes electrolyzers this way …translating directly into a unique cost advantage….Terraform’s hydrogen and CO2 are the chemical precursors for synthetic methane and methanol, which we make in our own synthetic fuel reactor. Combined, we make oil and gas out of sunlight and air. We are breaking the geological and geographical monopolies on oil production. In the limit, Terraform will deploy these electrolyzers by the millions and they will all be plug-and-play with solar PV arrays.

Using solar energy, drinking water could also be collected from thin air, especially in places like the island nation of Bahrain that are humid, yet seldom receive rain (Peru’s capital, Lima, also is humid, yet receives little rain):

Cody Friesen, an associate professor of materials science at Arizona State University, has developed a solar-powered hydropanel that can absorb water vapor at high volumes when exposed to sunlight.  It is a modern-day twist on an approach been used for centuries to pull water from the atmosphere, such as using trees or nets to “catch” fog in Peru, a practice that dates back to the 1500s and is still being used today….Friesen founded his own company Zero Mass Water in 2014 following his research on solar-powered hydropanels. Today the company is called Source Global, operates in more than 50 countries and has a private valuation of more than $1bn (£800m).

The panels work by using sunlight to power fans that pull air into the device, which contains a desiccant material which absorbs and traps moisture. The water molecules accumulate and are emitted as water vapor as the solar energy raises the temperature of the panel to create a high-humidity gas. This then condenses into a liquid before minerals are added to make it drinkable.

“That’s how we’re able to create water in most places in the world, even when it’s very dry,” says Friesen. “We’re headquartered in Scottsdale, Arizona, which is sub-5% relative humidity in the summer and we’re still making water. It’s a uniquely efficient and low-cost approach that enables us to go places where nobody else can go.”

The air, even in relatively dry climates, can hold a surprising amount of water. The Earth’s atmosphere as a whole contains about six times as much water as the planet’s rivers.

In addition, there are now floating desalination machines that use no electricity, which are “100% mechanically driven”: “Oneka’s floating desalination machines – buoys anchored to the seabed – use a membrane system that is solely powered by the movement of the waves. The buoys absorb energy from passing waves, and covert it into mechanical pumping forces that draw in seawater and push around a quarter of it through the desalination system. The fresh, drinking water is then pumped to land through pipelines, again only using the power provided by the waves.”