Australian scientists at the University of New South Wales say they have become the first to achieve 25 percent efficiency in a silicon solar cell.

The university's Australian Research Council Photovoltaic Center of Excellence also held the previous world record of 24.7 percent silicon solar cell efficiency. A revision of the international standard by which solar cells are measured resulted in the new record being achieved by a team led by Professors Martin Green and Stuart Wenham.

Green said the jump in performance resulted from new knowledge about the composition of sunlight.

"Since the weights of the colors in sunlight change during the day, solar cells are measured under a standard color spectrum defined under typical operational meteorological conditions," he said. "Improvements in understanding atmospheric effects upon the color content of sunlight led to a revision of the standard spectrum in April. The new spectrum has a higher energy content both down the blue end of the spectrum and at the opposite red end with, dare I say it, relatively less green."

The researchers said the university's world-leading silicon cell is now six percent more efficient than the next-best technology.