Sunlight transformed into electricity 'efficiently' for first time ever

Scientists have made a breakthrough by converting sunlight into electricity for the very first time with over 40 percent efficiency.

The record efficiency was achieved by UNSW Australia's solar researchers in outdoor tests in Sydney, before being independently confirmed by the National Renewable Energy Laboratory (NREL) at their outdoor test facility in the United States.

The 40 percent efficiency milestone is the latest in a long line of achievements by UNSW solar researchers spanning four decades. These include the first photovoltaic system to convert sunlight to electricity with over 20 percent efficiency in 1989, with the new result doubling this performance.

Professor Martin Green said that the new results were based on the use of focused sunlight, and were particularly relevant to photovoltaic power towers being developed in Australia.

Power towers are being developed by Australian company, RayGen Resources, which provided design and technical support for the high efficiency prototype. Another partner in the research was Spectrolab, a US-based company that provided some of the cells used in the project.

A key part of the prototype's design was the use of a custom optical bandpass filter to capture sunlight that was normally wasted by commercial solar cells on towers and convert it to electricity at a higher efficiency than the solar cells themselves ever could.

Such filters reflect particular wavelengths of light while transmitting others.

ARENA CEO Ivor Frischknecht said that the achievement was another world first for Australian research and development and further demonstrates the value of investing in Australia's renewable energy ingenuity.

The paper is due to be published in the Progress in Photovoltaics journal, and would be presented at the Australian PV Institute's Asia-Pacific Solar Research Conference.