Australian engineers in advanced photovoltaics have smashed the world efficiency record for perovskite solar cells, the cheap, easy to produce material which holds major potential for the future of renewable energy.
The team at the University of New South Wales (UNSW) in Sydney achieved a 12.1 per cent energy conversion efficiency rating for a 16 cm2 (2.5 sq in) perovskite solar cell, which is at least 10 times bigger than the current certified high-efficiency perovskite solar cells.
The breakthrough was announced by Anita Ho-Baillie, a Senior Research Fellow at the Australian Centre for Advanced Photovoltaics (ACAP), at the recent Asia-Pacific Solar Research Conference in Canberra. Australia is a leading proponent in solar cell research; the ACAP is a national research collaboration based at UNSW, and partnered by the University of Queensland, Monash University, the Australian National University, the University of Melbourne and the CSIRO Manufacturing Flagship, a key foundation of the country’s sustainable manufacturing strategy.
The research is backed by $3.6 million in funding through the Australian Renewable Energy Agency’s (ARENA) ‘solar excellence’ initiative. ARENA CEO Ivor Frischknecht said: “In the future, this world-leading R&D could deliver efficiency wins for households and businesses through rooftop solar as well as for big solar projects like those being advanced through ARENA’s investment in large-scale solar.”
Ho-Baillie added: “This is a very hot area of research, with many teams competing to advance photovoltaic design. Perovskites came out of nowhere in 2009, with an efficiency rating of 3.8 per cent, and have since grown in leaps and bounds. These results place UNSW among the best groups in the world producing state-of-the-art high performance perovskite solar cells. And I think we can get to 24 per cent within a year or so.”
Her team has also achieved an 18 per cent efficiency rating on a 1.2 cm2 single perovskite cell, and an 11.5 per cent for a 16 cm2 four-cell perovskite mini-module.
Perovskite is a structured compound, where a hybrid organic-inorganic lead or tin halide-based material acts as the light-harvesting active layer. Cheap to produce and simple to manufacture, the compound can even be spray-coated, printed or painted onto surfaces.
Ho-Baillie said: “The diversity of chemical compositions also allows cells be transparent, or made of different colours. Imagine being able to cover every surface of buildings, devices and cars with solar cells.”
The solar cells are made from crystals grown into a particular structure called perovskite. As they are much easier and more cost-efficient to produce than traditional silicon cells, the technology has been advancing fast. Worldwide, engineers are working to create smooth layers of perovskite with large crystal grain sizes in order to increase photovoltaic yields. However, perovskite cells are currently prone to fluctuating temperatures and moisture, making them last only a few months without protection.
ACAP director Professor Martin Green said the project’s goal is to lift perovskite solar cell efficiency to 26 per cent: “We will capitalise on the advantages of perovskites and continue to tackle issues important for commercialisation, like scaling to larger areas and improving cell durability.”
Featured image: Dr Anita Ho-Baillie, leader of the team which has set a new efficiency record for the largest certified perovskite solar cell (Credit: University of New South Wales)