Magic solar milestone reached

UNSW solar cell engineers have laid claim to another world record: this time the milestone of 25 per cent efficiency for a silicon solar cell.

Solar record inside

UNSW's ARC Photovoltaic Centre of Excellence has again asserted its leadership in solar cell technology by reporting the first silicon solar cell to achieve the milestone of 25 per cent efficiency.

The Centre already held the world record of 24.7 per cent for silicon solar cell efficiency. Now a revision of the international standard by which solar cells are measured, has delivered the significant 25 per cent record to the team led by Professors Martin Green and Stuart Wenham and widened their lead on the rest of the world.

Centre Executive Research Director, Scientia Professor Martin Green, said the new world mark in converting incident sunlight into electricity was one of six new world records claimed by UNSW for its silicon solar technologies.

Professor Green said the jump in performance leading to the milestone resulted from new knowledge about the composition of sunlight.

"Since the weights of the colours in sunlight change during the day, solar cells are measured under a standard colour spectrum defined under typical operational meteorological conditions," he said.

"Improvements in understanding atmospheric effects upon the colour 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 recalibration of the international standard, done by the International Electrochemical Commission in April, gave the biggest boost to UNSW technology while the measured efficiency of others made lesser gains. UNSW's world-leading silicon cell is now six per cent more efficient than the next-best technology, Professor Green said. The new record also inches the UNSW team closer to the 29 per cent theoretical maximum efficiency possible for first-generation silicon photovoltaic cells.

For more on this story go to the Faculty of Engineering news page.

Media Contact: Peter Trute | 02 9385 1933 | 0410 271 826 |