Deep-Earth Hydrogen: The Race to Uncover a Cheap Clean-Energy Source

Scientists and investors are drilling for hydrogen gas trapped underground in dozens of countries, hoping to unlock a cheap, scalable green energy source. Early estimates suggest Earth may host trillions of tonnes of geologic hydrogen, but the size and extractability of deposits are still unproven and results could take months to years. If viable, underground hydrogen could accelerate the shift away from fossil fuels, but questions remain about how quickly hydrogen forms, migrates, persists, and economics—making it a high-stakes bet as campaigns like those in Kansas, Mali, and elsewhere gather data.