Powering next-gen solar panels: Breakthrough tech hits 30% efficiency, cooler temperature

Researchers from the University of New South Wales (UNSW) Sydney have developed a solar cell technology that could lead to higher-efficiency silicon photovoltaics.

The team has devised a new method with the potential to increase solar panel efficiency to over 30%, a notable improvement on the 20-25% efficiency of typical commercial panels.

The approach may also allow panels to operate at temperatures up to 2.4°C (36.32°F) cooler, a factor that could extend their functional lifespan by an estimated 4.5 years.

The development addresses a key materials challenge. Previous work in this area often used a molecule called tetracene, which is chemically unstable in air and thus unsuitable for commercial manufacturing.

Using robust, photostable organic molecule

The UNSW team reports the successful use of a more robust and photostable organic molecule, dipyrrolonaphthyridinedione (DPND), that is compatible with crystalline silicon photovoltaics and scalable production methods.

“We’ve developed a practical pathway to higher output silicon solar cells, without the cost and complexity of tandems, that industry can now trial,” said lead researcher Professor Ned Ekins-Daukes, Head of UNSW’s School of Photovoltaic and Renewable Energy Engineering (SPREE).

The technology is based on a process known as “singlet fission.” In a conventional silicon solar cell, a high-energy photon from the blue or green part of the light spectrum is absorbed and creates a single electron-hole pair. 

Any energy the photon has above the silicon bandgap is quickly lost as heat, a process known as thermalisation loss, which limits overall efficiency. The singlet fission process operates differently.

“When a singlet fission material is layered over a silicon cell, it captures the high energy photons and splits it into two excitons that match silicon’s bandgap, and each form an electron-hole pair,” explained the researchers in a press release.

“This doubles the electrical yield from the blue, high energy photons, and reduced the heat generation.”

Potential commercial implications are considerable

An increase in power output per panel would mean fewer panels are required to achieve a target energy capacity. This can lower associated balance-of-system costs, which include mounting hardware, wiring, and installation labor, in addition to reducing the physical footprint for an installation.

The reduction in waste heat offers further benefits. Beyond extending the panel’s long-term durability, cooler operating temperatures can improve real-time performance, as silicon cell efficiency typically decreases as temperature rises.

The approach is also distinct from tandem solar cells, which stack multiple semiconductor junctions and require a more complex redesign of the entire cell architecture. The singlet fission layer is designed to be an addition to existing silicon technologies, suggesting a more direct integration path.

The UNSW team has filed for patent protection for their work. The project is now moving towards scaling up the production of the DPND molecules to prepare for pilot-line manufacturing trials.

“We’re now moving from fundamental science to practical solar products,” concluded Dr Jessica Yajie Jiang of the research team.

“The impact for industry, investors and the environment could be profound.”