“Spicing up” solar panels could make them more effective


Chili peppers are not only good for health or for spicing up dishes. A team of Chinese scientists has observed that solar panel cells treated with capsaicin, the active component in chili pepper, were more effective at converting solar power into electricity.

We already knew that ultra-thin lead-based solar cells absorb light more effectively than silicon-based ones; even so, they let some of the solar energy escape in the form of heat. The solution to address this loss may consist in adding… a little more heat. 

Researchers from Shanghai University suspected that capsaicin would have an energy-boosting effect, as it releases electrons able to continue carrying the electric charge. They therefore added it to ultra-thin perovskite (a lead hybrid or a tin halide) solar cells during the manufacturing process to obtain samples to be tested in the laboratory. 

They then tested these experimental cells treated with capsaicin, exposing them to artificial light imitating sunlight, and measured the electricity passing through them. Their results showed that capsaicin had a power conversion of 21.88% compared to 19.1% for cells not treated with chili pepper. 

The team then analyzed the solar cells with spectroscopy. It noted that the addition of capsaicin freed up a greater number of electrons available for conducting the current to the solar cells’ surface. Energy leaks due to heat are therefore reduced. 

The researchers have not yet completely elucidated the exact mechanism behind this process. They suppose that the capsaicin molecules react with the lead ions in the solar cells and release electrons to conduct the current. 

In any case, capsaicin would be an advantageous solution because it is natural, inexpensive, sustainable and found abundantly in nature. 

According to Tsutomu Miyasaka from the University of Yokohama, many natural organic compounds are currently being tested to check if they have boosting effects similar to capsaicin. These compounds would improve solar cell efficacy and stability at a very low cost. 


“Solar panels capture more sunlight with capsaicin - the chemical that makes chili peppers spicy,” The Conversation, January 13, 2021 - theconversation.com/solar-panels-capture-more-sunlight-with-capsaicin-the-chemical-that-makes-chili-peppers-spicy-152901