New efficiency record for large perovskite solar cell

Perovskite solar cells hold major potential for the future of renewable energy thanks to being cheap, easy to produce and are so flexible that they can even be sprayed or painted on surfaces. Now a team of Australian researchers has just set the efficiency record for the biggest perovskite solar cells so far.

A team at the University of New South Wales (UNSW) in Sydney, Australia claims to have achieved a 12.1 percent energy conversion efficiency rating for a 16 cm² (2.5 sq in) perovskite solar cell, which is at least 10 times the size of current certified high-efficiency perovskite cells.

In the last year or so, we've seen other smaller perovskite cells and some hybrid combinations hit efficiency levels above 20 percent. The UNSW team also achieved 18 percent efficiency for a 1.2 cm² (0.2 sq in) single perovskite cell, and 11.5 percent for a 16 cm² (2.5 sq in) four-cell perovskite mini-module.

"Perovskites came out of nowhere in 2009, with an efficiency rating of 3.8 percent, and have since grown in leaps and bounds," said Anita Ho-Baillie, a Senior Research Fellow at the UNSW's Australian Centre for Advanced Photovoltaics. "I think we can get to 24 percent within a year or so."

The solar cells are made from crystals grown into a particular structure called perovskite. Smooth layers of perovskite with large crystal grain sizes allow the cells to absorb more light. The technology has been advancing fast and attracting plenty of attention thanks to its ease of production and low cost compared to silicon cells.

"The diversity of chemical compositions also allows cells be transparent, or made of different colors," said Ho-Baillie. "Imagine being able to cover every surface of buildings, devices and cars with solar cells."

Perovskite cells do have downsides like much less durability, something Ho-Baillie and her team say they're confident they can improve, while also shooting for higher levels of efficiency.

Source: UNSW