The quest for substitute fuels has become one of science’s major pre-occupations and finding ways to cheaply produce energy from the sun is a key battlefront. Researchers at Berkeley, California, have found a way to make cheaper, better solar cells using tiny nanopillar semiconductors measuring just billionths of a meter wide. The underlying theory is that a 3-D solar cell has more surface – and, therefore, will be a much more efficient light-collector – than the usual 2-D solar cell.