Scientists from the Universities of Oxford, Durham, and Toronto have published a groundbreaking study in Nature Reviews Earth & Environment, revealing the formation and accumulation of natural hydrogen in underground rock formations. This discovery opens up a new avenue for low-cost, low-emission energy that could revolutionize the global clean energy market and decrease dependency on fossil fuels. The research highlights the widespread presence of geological conditions conducive to natural hydrogen formation across various regions globally. Hydrogen, currently essential in industries with an annual market value of $135 billion, is projected to become a key component of carbon-free energy systems, potentially reaching a market value of $1 trillion by 2050. While the demand for hydrogen is expected to surge significantly, most of the current supply is derived from hydrocarbons, contributing to global carbon dioxide emissions. The study emphasizes the Earth's continental crust as a vast reservoir of hydrogen that has been produced for over a billion years, with the potential to meet human energy needs for the next 170,000 years. The researchers introduce an 'exploration recipe,' offering a comprehensive strategy to identify and extract hydrogen from natural sources efficiently. They address challenges such as underground microbes that consume hydrogen and emphasize the importance of preserving hydrogen in economic accumulations. By dispelling earlier theories and confirming the accumulation of hydrogen in various crustal formations, the study provides a practical guide for industry to access natural hydrogen reservoirs. The authors believe that their work presents a repeatable method for industries to transition towards cleaner energy sources, ultimately reducing reliance on fossil fuels and expanding access to clean energy.