A team led by Cornell University has developed a revolutionary solar device that, using sea water, produces green hydrogen Zero emissions and, as a by -product, generates drinking water. This low -cost technology could drastically reduce the price of hydrogen within the next 15 years.
The result of the collaboration between Cornell, Mit, Johns Hopkins and Michigan State University, the new HSD-WE device (Hybrid Solar Distillation-Water Electrolysis) represents a turning point in the field of sustainability. Measures just 10 × 10 centimeters, but is able to produce 200 milliliters of hydrogen per hourreaching a energy efficiency of 12.6% using exclusively natural sunlight and sea water.
In the long term, according to researchers’ estimates, this technology could lower the cost of green hydrogen to 1 dollar per kilograma crucial step to reach zero net emissions by 2050.
“Energy and water are fundamental resources for our daily life, but normally one requires the consumption of the other,” he explains Lenan Zhangprofessor at Cornell Engineering and project manager. “Today two thirds of the world population suffer from scarcity of water. And even green hydrogen is expensive precisely because it requires deionized, pure and expensive water.”
Zhang, who previously worked on MIT developing methods to deduce the sea water through sun energy, extended the concept including hydrogen production. “We wondered: what are the most abundant and free resources on earth? The sun and the sea,” he says.
An integrated system that uses each component of solar energy
The device created by the Zhang team resolves one of the main limitations of photovoltaic panels: the poor efficiency. Only 30% of the sunlight is transformed into electricity, while the rest disperses in heat. This system, on the other hand, also captures the residual heatusing it for heat and evaporate sea water.
The key is a capillary wick mechanism: trap the water in a very thin film, placed directly in contact with the sun panel. In this way, it is sufficient to warm only the film and not great volumes of water, improving theEvation of evaporation over 90%.
Once evaporated, the water leaves behind the salt and condenses like desecking steamready to be used in a electrolyser that split it in oxygen and hydrogen.
Production of hydrogen and drinking water in a single compact device
The strength of this technology lies in his multifunctional integration. The design combines distillation, electrolysis, photovoltaic and multiple energy transfers (sunny, electric, thermal and chemical). The result? A sufficient production of pure water to generate hydrogenwith a surplus of drinking water.
“For the first time we managed to generate enough water to support the production of hydrogen, and in addition there is excess water that you can drink. Two objectives, only one device,” says Zhang.
Currently, the cost of green hydrogen production is around 10 dollars per kilogrambut using unlimited resources such as sun and sea, this figure could drastically go down within a few years.
Zhang also imagines a future in which the system comes integrated into solar parks: The sea water would cool the panels improving its efficiency and prolonging its duration.
