Researchers at the Australian National University (ANU), in Canberra, have set a new record for the conversion of sunlight into energy.

The ANU team is working on developing ‘tandem solar cells’, which involves stacking a perovskite solar cell (a new type of solar cell which uses organic and inorganic materials in a purpose built structure that enhances light absorption) on top of a silicon cell (which are made from only inorganic materials and can only absorb red light), to generate twice as much energy out of sunlight.

The researchers have set a new efficiency record of 27.7 per cent for mechanically-stacked perovskite-silicon tandem cells – meaning 27.7 per cent of sunlight is converted into energy. Typical rooftop solar installed at the moment has an efficiency of approximately 20 per cent.  

Professor Kylie Catchpole of the ANU team said that this percentage would only need to increase slightly, to approximately 30 per cent, before the technology could be rolled out around the world.  

“Silicon solar cells currently dominate the market, however the efficiency of silicon solar cells is going to reach the limit in the next five to ten years. This result demonstrates the potential of tandem solar cells,” Professor Catchpole said. 

“They can make better use of certain parts of the solar spectrum – for example, high energy blue photons. This will lead to more efficient and more cost effective solar cells and solar energy sources.”

Professor Catchpole said that higher efficiency means each section of a solar panel is producing more power.

Read the full article in Energy Magazine, featuring commentary by Professor Kylie Catchpole