While Germany has achieved 40.7% efficiency it was only in a lab environment and could not be easily mass produced. The work in Australia is still largely refocusing light to large concentrators rather than direct conversion of solar energy.
Australia’s solar researchers have converted over 40 percent of the sunlight hitting a solar system into electricity, the highest efficiency ever reported. A key part of the prototype’s design is the use of a custom optical bandpass filter to capture sunlight that is normally wasted by commercial solar cells on towers and convert it to electricity at a higher efficiency than the solar cells themselves ever could.
The record efficiency was achieved 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 work was funded by the Australian Renewable Energy Agency (ARENA) and supported by the Australia-US Institute for Advanced Photovoltaics (AUSIAPV).
“This is the highest efficiency ever reported for sunlight conversion into electricity,” UNSW Scientia Professor and Director of the Advanced Centre for Advanced Photovoltaics (ACAP) Professor Martin Green said.
“We used commercial solar cells, but in a new way, so these efficiency improvements are readily accessible to the solar industry,” added Dr Mark Keevers, the UNSW solar scientist who managed the project.
The 40% 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% efficiency in 1989, with the new result doubling this performance.
“The new results are based on the use of focused sunlight, and are particularly relevant to photovoltaic power towers being developed in Australia,” Professor Green said.