Smaller, cheaper, faster: Does Moore’s law apply to solar cells?
By Dr. Matthew Watson
The sun strikes every square meter of our planet with more than 1,360 watts of power. Half of that energy is absorbed by the atmosphere or reflected back into space. 700 watts of power, on average, reaches Earth’s surface. Summed across the half of the Earth that the sun is shining on, that is 89 petawatts of power. By comparison, all of human civilization uses around 15 terrawatts of power, or one six-thousandth as much. In 14 and a half seconds, the sun provides as much energy to Earth as humanity uses in a day.
The numbers are staggering and surprising. In 88 minutes, the sun provides 470 exajoules of energy, as much energy as humanity consumes in a year. In 112 hours – less than five days – it provides 36 zettajoules of energy – as much energy as is contained in all proven reserves of oil, coal, and natural gas on this planet.