Granted, the Earth does need much of this solar energy to drive its weather, so let’s look only at the unused portion of sunlight that is reflected back into space, known as the albedo. Earth’s average albedo is around 30%, meaning that roughly 52 petawatts of energy is reflected by the Earth and lost into space every year. Compare this number with global energy-consumption statistics. Annually, the energy lost to space is the combined equivalent of 400 hurricanes, 1 million Hoover Dams, Great Britain's energy requirement for 250,000 years, worldwide oil, gas and coal production for 387 years, 75 million cars, and 50 million 747s running perpetually for one year (not to mention 1 million fictional DeLorean time machines!).