A team of South Korean researchers claims that fish oil – best known as a miracle health supplement – could be the key to a next generation of solar panels with “unprecedented” efficiency.
The researchers found that a fish oil and water-based emulsion placed over solar panels in a filter can capture ultraviolet light and convert it into thermal energy. This boosted the conversion efficiency of the panels.
“Emulsion technology is already well established” and used in the cosmetics and food industries, among others, said Jae Won Lee, a professor from the Korea Maritime & Ocean University who led the research.
“Therefore, emulsion filters can be easily applied to existing systems,” he added.
Announcing the results of the research today (Friday), the university said that photovoltaic (PV) modules used in solar panels suffer from a low conversion efficiency of around 20% because they can only convert near-infrared wavelengths into electricity.
Other wavelengths simply heat up the PV module, reducing its efficiency.
To counter this, scientists have developed photovoltaic-thermal (PVT) systems that carry away heat generated through a heat exchanger using a coolant fluid – either air or liquid.
This cools down PV modules, increasing their efficiency, while the heat captured is used as thermal energy.
Scientists have also developed “de-coupled” PVT systems that use liquid filters, placed over the PV modules, to capture wavelengths of sunlight that contribute minimally to electricity generation. These include ultraviolet (UV), visible light and near-infrared.
However, the university says that water, “a popular liquid filter, cannot absorb UV rays.”
Now, the team of researchers led by Lee have found that a mixture of fish oil and water absorbs both infrared and UV light, “increasing the energy harvesting potential of de-coupled PVT systems.”
The university claims that the fish oil filter had a conversion efficiency of 84.4% compared to systems with heat exchangers (70.9%) and de-coupled PVT systems using a water filter (79.3%). It also decreased the temperature of the modules from 46.7C to 33.1C.
The researchers found their system can even be adapted to the weather. “For example, during summer, the fluid in the liquid filter could be bypassed to maximize electricity production, while in winter, the liquid filter could capture thermal energy for heating applications.”