The total solar energy absorbed by Earth’s, oceans, atmosphere, and land masses is approximately 3,850,000 exajoules (EJ) per year. To put this into perspective, that’s more energy in one hour than all of human civilization used in the year 2002. In one year, incoming solar radiation contains more energy than all of the non-renewable sources of energy (coal, oil, natural gas, and mined Uranium) found on the planet.

Only a small fraction of incoming solar radiation is captured by plants for photosynthesis (3,000 EJ or 0.078%).