All four elements seemed to have been mastered by restless geniuses: power plants take energy from coal, gas, atom, river water, wind, and sunlight – from everything they learned to extract the very power that gives light, heat, and food. And, sure thing, leaving 70% of the planet undeveloped seemed like blasphemy to energy experts. Scientists say the sea is the world's largest battery; off the coast of the United States alone, the theoretical annual energy potential of the waves is estimated at 2.64 trillion kilowatt-hours, equivalent to about 64% of total US utility electricity generation in 2021.