A mountain of hydrogen is lurking beneath Earth's surface — and scientists say that just a fraction of it could break our dependence on fossil fuels for 200 years.
New research suggests the planet holds around 6.2 trillion tons (5.6 trillion metric tons) of hydrogen in rocks and underground reservoirs. That's roughly 26 times the amount of oil known to be left in the ground (1.6 trillion barrels, each weighing approximately 0.15 tons) — but where these hydrogen stocks are located remains unknown.
