Australian researchers at the University of Adelaide have made significant strides in reducing the cost of producing green hydrogen by utilizing an unconventional ingredient: urine. The researchers have developed two methods that can potentially decrease the cost of renewable hydrogen by as much as 27%. This breakthrough comes at a crucial time, as the US government aims to reach a target price of $US2 per kilogram for green hydrogen. The process involves using urea, found in urine, to split water into oxygen and hydrogen with significantly less energy consumption compared to traditional electrolysis methods. However, the researchers encountered an unexpected obstacle when they found that Australia's wastewater is too clean to facilitate the process effectively. Despite this challenge, the team remains optimistic and plans to scale up their experiments beyond the laboratory. By utilizing urea from sources outside Australia's waste stream and incorporating cheaper catalysts, the researchers aim to surpass the US cost target and produce green hydrogen for less than $US2 per kilogram. The potential applications of green hydrogen are vast, including powering heavy industry, long-haul trucks, and enabling the production of green metals such as iron. While the process may yield toxic by-products, the researchers have devised methods to minimize environmental harm by producing harmless nitrogen gas instead. Ultimately, the goal is to create green hydrogen in a cost-effective and carbon-neutral manner. With further development and scaling up of the experiments, the team envisions achieving a production cost between $US1.50 to $US1.95 per kilogram, aligning with the US Department of Energy's targets for the coming years.