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. (…)

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 miniscule 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. (…)

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. (…)

The cost of solar, in the average location in the U.S., will cross the current average retail electricity price of 12 cents per kilowatt hour in around 2020, or 9 years from now. (…) 10 years later, in 2030, solar electricity is likely to cost half what coal electricity does today.

{ Scientific American | Continue reading | via/more: Overcoming Bias }

photo { Eylül Aslan }

economics, elements, technology | November 11th, 2011