To truly compete with coal, solar power needs to be at least as cheap or cheaper, something that is quite difficult to achieve today. Solar panels are big, clunky, heavy, require special installation, and, if they break, replacing them can be quite expensive. With these problems in mind, Nanosolar has devised a way of making solar panels that are as thin as paint and come from a printing press.

The PowerSheet is made from a layer of solar-absorbing nano-ink that is printed onto a foil-thin metal sheet. According to the company, this technology has several key advantages. It is cheaper to make, as the process can produce several hundred feet of solar panels per minute, making it viable to generate a watt of electricity for less than $1, almost cheaper than what it would cost to produce by burning coal.

Because of the ever-increasing costs of energy and the obvious environmental impact of burning up fossil fuels, turning to alternative energy sources such as solar energy is a priority. Nanosolar’s breakthrough made it worthy of being named Popular Science’s green innovation of the year.

+ Nanosolar Powersheet