Figure 1. Above - Hollow silicon nanospheres can absorb the same amount of light as a 1 μm thick film using only 50 nm worth of material. Below - Embedding a metal contact grid within an array of silicon nanopillars can make the metal nearly invisible to incoming light, dramatically boosting absorption in the silicon.

Sunblock: three misconceptions hampering access to solar energy in the developing world

By Vijay Narasimhan In August, for the first time, one billion people logged into Facebook on a single day, a staggering testament to the reach of technology in our daily lives. But about the same number of people can’t even fathom logging into Facebook because they lack basic access to electricity. Electricity means more than…