Green hydrogen can power heavy vehicles and decarbonize sectors while emitting no carbon dioxide. But, because the water-splitting equipment, known as electrolyzers, is intended to function with clean water, increasing the usage of green hydrogen might worsen worldwide freshwater problems. To solve this, research teams are already claiming advancements like seawater to provide an infinite supply of green hydrogen in face of freshwater scarcity.
India plans to produce five million metric tonnes of renewable hydrogen by 2030. Nevertheless, there is practically no discussion of its fundamental requirement, water. Nowadays, India utilizes 6 million tonnes of grey hydrogen. If India produced the same quantity of green hydrogen, it would need 132 to 192 million tonnes of water for the 6 million tonnes of green hydrogen.
The water need will rise further if the government follows its assertion that India can produce 10 million metric tonnes of green hydrogen per year. As green hydrogen generation increases, pressure on the world’s freshwater supply may increase.
According to the International Energy Agency, every kilogram of green hydrogen generated requires 9 liters of distilled water. In water-stressed places, access to fresh water is a challenge for green hydrogen production.
Although seawater is practically endless, separating it presents its own set of challenges. Due to the presence of minerals and salts in seawater, electrolyzers will not function as well as they do when freshwater is utilized. It causes electrolyzers to fail in hours when they should last for years.
However, attempts are being undertaken to utilize saltwater or unclean water to produce green hydrogen. Nevertheless, they are simply experimental endeavors. Recent research has hinted at the possibility of utilizing saltwater in electrolysis without treatment. Countries such as Spain have also conducted preliminary studies on utilizing treated saltwater in electrolysis to create fresh water.
According to scientists, studies utilizing seawater to provide an infinite supply of green hydrogen in face of freshwater scarcity have offered optimism. If it becomes financially viable, it has the potential to alleviate the primary water issue. He did, however, warn that the additional need for water treatment would almost certainly add to the extra energy load and raise manufacturing costs.
India plans to capitalize on its early mover advantage, as well as low-cost renewables, to enter the green hydrogen industry. Yet, the faster a country improves its technology and reduces its overall manufacturing costs, the better it will be able to compete worldwide.
Source: Science Daily