Capsaicin, the chemical in chilli peppers that makes them spicy, has been discovered as an efficient addition to solar panels. A team of scientists from East China Normal University in Shanghai, led by Qinye Bao, found that adding the chemical to solar cells helped boost the efficiency of heat absorption on perovskite solar panels.
Perovskite Solar Panels
Discovered by Tsutomu Miyasaka at the University of Yokohama in 2009, the perovskite solar panel has recently become a popular choice due to its green nature. Despite the purpose of solar panels being to promote green energy, building solar panels can produce an immense carbon footprint. Industry standard solar panels, made with crystalline silicon wafers, have a significantly higher carbon footprint and environmental impact, compared to the perovskite panels. Studies show that perovskite panels generate only 43.4% of the Silicon panel production emissions.
However, the limitation of these innovative, green panels, is that, despite their efficiency in absorbing heat, they can struggle to efficiently convert it to energy. Furthermore, they decay more quickly than their traditional counterparts.
Bao and his team speculated that the chemical nature of capsaicin may help contribute to energy conversion by freeing up electrons, if added to the panels in the manufacturing process. They conducted a study, treating solar cells with capsaicin, exposing them to artificial sunlight, and measuring the electrical current.
The studies showed that capsaicin effectively improved power conversion, with a rate of 21.88%, compared to 19.1% in the capsaicin-less solar cells. Their theory of capsaicin’s capacity to free up electrons was also valid, as a spectroscopy analysis demonstrated a greater number of free electrons in the treated cells’ surface. Increased electrons reduce energy leakage via heat, as they are able to conduct the current more efficiently.
The full explanation behind this efficiency improvement is still under review. The team suspect that the capsaicin molecules and the solar panel’s led ions react, which results in more free electrons.
Utilising earth’s chemicals in renewable energy solutions is the perfect partnership. Qinye Bao agrees. “It is our priority to select sustainable forest-based biomaterials,” he explains. “Capsaicin is low-cost, natural, sustainable and Earth-abundant.” This is not the first innovation in food-based solar panel treatment (surprisingly). A team at Liverpool led by John Major discovered that magnesium chloride, found in tofu and bath salts, improved the efficiency of traditional solar panel cells. Despite a 13% decline of renewable energy power in 2020, due to COVID-19, the International Energy Agency expects a huge boost in 2021.