US scientists cut 47% green hydrogen production cost using wastewater

US scientists at Princeton University have developed a breakthrough method to produce green hydrogen fuel using reclaimed wastewater instead of costly ultrapure water. Traditionally, green hydrogen production via electrolysis requires ultrapure water to prevent impurities from damaging the proton exchange membrane in electrolyzers. The Princeton team discovered that calcium and magnesium ions in wastewater cause scaling and rapid performance decline in standard electrolyzers. To overcome this, they acidified the reclaimed wastewater with sulfuric acid, which provides abundant protons that outcompete these problematic ions, maintaining ion conductivity and enabling continuous hydrogen production for over 300 hours without system failure. This innovation significantly reduces both the environmental impact and cost of hydrogen production. Using reclaimed wastewater cuts water treatment costs by approximately 47% and reduces energy consumption related to water purification by about 62%. The acid used in the process is continuously recirculated, enhancing sustainability. The researchers are now collaborating with industry partners to scale up the technology and test it with pretreated seawater. Their work supports broader efforts to integrate