New solar battery can be used to produce clean water

U.S. military-funded researchers believe they have found a way to create an inexpensive device that not only gives their soldiers clean water to drink while on duty, but could also help solve the global clean water crisis, especially in developing countries with polluted water sources. University of Rochester researchers say their breakthrough is based on laser processing technology and black aluminum.

These technologies make it highly absorbent and super absorbent, meaning it can separate water and pull it onto surfaces. It is then combined with a new solar battery to use as a solar water purifier.

When the solar panel is immersed in water at an angle facing the sun, it "draws" a thin film of water onto the surface of the metal plate. At the same time, this black surface is capable of retaining almost 100% of the energy it absorbs from the sun to heat the water. Furthermore, the surface structure of the material is hygroscopic (wicking) which changes the bonds between water particles, thereby increasing the efficiency of the evaporation process.

Professor Chunlei Guo said that “Three things together make the technology ideal and work better with almost 100% efficiency, which could be a simple application, high durability, low cost to solve the global water crisis, especially in developing countries".

Laboratory testing has shown that the device can reduce the presence of contaminants to a safe and drinkable level.

The researchers say that, so far, the method of evaporating water (separating clean water) has mainly relied on solar radiation to heat it. This can heat large volumes of water but only the top layer evaporates. Instead, this innovation in solar cell application "pulls" a thin layer of water out of the reservoir onto the surface of the panel and thereby evaporates this thin layer of water using solar energy.

According to Chunlei: “Moreover, because we use an open grooved surface, it is very easy to clean the device. The biggest advantage is that the angle of the solar panels can be adjusted continuously to face the sun directly, which maximizes solar energy absorption."