Solar panel efficiency can skyrocket. All it takes is one thing.

Current photovoltaics stand and fall on silicon. It is a proven and relatively inexpensive material, but it has been reaching its physical limits for some time. Regardless of what we do, the best commercial panels convert only about 27% of solar radiation into electricity, with common models installed on house roofs hovering around 22%. The theoretical maximum is only slightly higher, at 29.4%, with tandem cells capable of surpassing the 30% mark. The rest of the precious energy is converted into heat.

Scientists from the University of New South Wales (UNSW) in Sydney are now trying to break this imaginary barrier. The Omega Silicon team is building on a process called "singlet fission." Simply put, it is a trick to get two smaller packets of energy from one particle of light (a photon). Each of these can then create a separate electrical charge.

Details on the topic are available on the websites of ACS Energy Letters, University of New South Wales, Interesting Engineering, and Tech Xplore.

In the article, you will read:

• Silicon panels are hitting limits, but "singlet fission" offers higher efficiency.

• The new organic material DPND replaces the unstable tetracene in the fission process.

• The theoretical efficiency of panels could increase from 27% up to 45%.

The idea is to utilize energy that is currently being wasted. Photons in the blue part of the spectrum carry a lot of energy, but silicon cells cannot convert it into electricity, and most of it is converted into heat. However, the new process captures this excess energy, which would otherwise be converted into heat, and converts it into a second dose of electricity.

The foundation is a new compound

The scientific team is building on more than ten years of research. Led by Professor Tim Schmidt, its members used magnetic fields to reveal how singlet fission occurs at the molecular level. If the experimental results are confirmed outside the laboratory, we could witness the birth of a new generation of solar panels.

This idea is not entirely new, but previous experiments failed due to the material used. Although the commonly used tetracene worked in the lab, it decomposed very quickly in normal air and at typical humidity.

For the first time, the UNSW team used the compound DPND (dipyrrolonaphthyridinedione). It is a stable organic material derived from industrial pigments that easily withstands external conditions.

Its implementation should not be particularly difficult. The trick is to apply an ultra-thin organic layer of this pigment to the cell, which can be applied to existing silicon photovoltaic panels without major structural changes.

Solar panel efficiency up to 45%

As Ben Carwithen, a postdoctoral researcher from the UNSW School of Chemistry, says: "It’s basically adding a layer to the existing design to help capture more energy." Although this is still an experimental solution, initial tests showed that the split light can indeed deliver an additional electrical current to the cell.

The potential is huge – theoretical efficiency could jump from today's 27% to a record 45%. This would mean almost double the output without the need to build new power plants or take up more land with photovoltaic panels.

The project is also backed by the Australian Renewable Energy Agency (ARENA), which included it in its Ultra Low Cost Solar program. The program's goal is to reduce the cost of solar electricity to below 30 cents per watt and increase efficiency above 30% by 2030.

However, the team remains realistic and tempers excessive expectations. "A major breakthrough could happen next week, but realistically it will probably take five years," says Carwithen.

Source: https://zive.aktuality.sk/