Sent to you via Google Reader The Moore's Law of solar energy This article was originally posted at Scientific American. It's reprinted with permission. 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. Seven hundred 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. If humanity could capture one tenth of one percent of the solar energy striking the Earth — one part in one thousand — we would have access to six times as much energy as we consume in all forms today, with almost no greenhouse gas emissions. At the current rate of energy consumption increase — about 1 percent per year — we will not be using that much energy for another 180 years. It's small wonder, then, that scientists and entrepreneurs alike are investing in solar energy technologies to capture some of the abundant power around us. Yet solar power is still a minuscule fraction of all power generation capacity on the planet. There is at most 30 gigawatts of solar generating capacity deployed today, or about 0.2 percent of all energy production. Up until now, while solar energy has been abundant, the systems to capture it have been expensive and inefficient. That is changing. Over the last 30 years, researchers have watched as the price of capturing solar energy has dropped exponentially. There's now frequent talk of a "Moore's law" in solar energy. In computing, Moore's law dictates that the number of components that can be placed on a chip doubles every 18 months. More practically speaking, the amount of computing power you can buy for a dollar has roughly doubled every 18 months, for decades. That's the reason that the phone in your pocket has thousands of times as much memory and ten times as much processing... Sent from my iPhone