A groundbreaking innovation from a Cornell University-led team has introduced a compact solar distillation-water electrolysis device that not only generates green hydrogen but also produces potable water from seawater. The device, measuring just 4 inches per side, can currently produce 200ml of hydrogen per hour with 12.6% energy efficiency. If scaled up, it is estimated that the cost of green hydrogen could be reduced to $1 per kilogram within the next 15 years. The project addresses the pressing challenge of green hydrogen production without compromising freshwater resources. By utilizing the wasted heat from solar cells, the device successfully desalinates seawater, tapping into the vast potential of ocean water for sustainable fuel production while also addressing global water scarcity issues. The integration of desalination, electrolysis, and solar energy conversion in this technology not only ensures a sufficient supply of hydrogen but also provides additional potable water. Moreover, the device offers the added benefit of potential applications in cooling photovoltaic panels, enhancing their efficiency and longevity. The team's innovation marks a significant stride towards carbon-free energy production, emphasizing the importance of cost-effectiveness for the widespread adoption of green hydrogen technologies. The multifaceted device not only showcases a promising solution to dual challenges of sustainable energy and water scarcity but also holds immense potential for future large-scale installations, contributing to a cleaner and more sustainable future.