Sydney, Apr 19 (IANS): A breakthrough could boost the output of low cost solar cells in rooftop panels by a whopping 40 percent, making them much more viable as an alternative energy source.

Tim Schmidt, professor of chemistry at the University of Sydney and his German partners from the Helmholtz Centre for Materials and Energy, have developed a "turbo for solar cells" that allows energy, normally lost in solar cells, to be turned into electricity.

Schmidt said using the upconversion technique, a process that harvests the part of solar spectrum currently unused by solar cells, eliminates the need for costly redevelopment of solar cells, the journal Energy & Environmental Science reports.

"We are able to boost efficiency by forcing two energy-poor red photons (light atoms) in the cell to join and make one energy-rich yellow photon that can capture light, which is then turned into electricity," Schmidt said, according to a Sydney statement.

"We now have a benchmark for the performance of an upconverting solar cell. We need to improve this several times, but the pathway is now clear," added Schmidt.

Australian Solar Institute executive director Mark Twidell said this is a great example of successful collaboration between leading Australian and German solar researchers.

"Together, Australia and Germany can accelerate the pace of commercialisation of solar technologies and drive down the cost of solar electricity," Twidell said.