Researchers at Hong Kong Polytechnic University have developed a new cooling system for solar panels, a system that increases energy production by almost 20%!
Researchers have discovered a way to make solar panels “sweat”, allowing them to cool in heat and thus increase energy production by almost 20%!
To do this, they applied a gel that absorbs water from the atmosphere, cooling the photovoltaic panels.
The gel is a mixture of carbon nanotubes in polymers with a calcium chloride that attracts water, which ultimately absorbs water vapor overnight, when the air is colder and humidity is higher. . As the temperature rises during the day, the freezing releases the water vapor retained during the night, which increases the efficiency of the solar panel.
Peng Wang, an engineer at Hong Kong Polytechnic University, and his team have come up with a way to trap the frost at the bottom of the traditional solar panel, so that during the day, they keep the panel cool.
The idea is for the gel to draw heat from the solar panel, evaporating the water absorbed by the gel overnight. Evaporated water is used to cool the solar panel the same way humans sweat, cooling the skin.
During the investigation, this method allowed a decrease of 10 ° C in the temperature of the solar panel, which caused a increase in electricity production from solar panels by around 15% and 19%.
As for the amount of gel needed to have this effect, it will depend on the ambient humidity. For example, in a desert, with 35% humidity, a 1 square meter solar panel needs 1 kg of gel to cool down, while a humidity of 80% only needs 300 grams of gel. per square meter of panel.
Jun Shou says that the increase in the efficiency of solar panels is significant, even saying that the 1% increase is already good, given the current market. Anything that can improve efficiency is great for renewables.
Disadvantages … all is not good in this solution. The researchers believe that the gel solution, when the solar panel is exposed to rain, can dissolve. Thus, calcium chloride will dissolve and affect its ability to absorb water.
This “problem” was even recognized by Wang, even with the frost at the bottom of the solar panel, which is supposed to be protected from the rain. Meanwhile, his team is developing a second-generation gel that won’t break down, even when wet.
The research team is looking for another option to retain and re-condense the water after the gel has evaporated, and potentially use the collected water to clean the solar panels, as well as to cool them.