A breakthrough for the solar energy industry as a San Diego research team has recently developed a type of paint that can trap light and also withstand intense heat for many years. The paint is made of nano-particle materials that can endure outdoor temperatures of 1,380 degrees Fahrenheit (750 degrees Celsius) without peeling or cracking.
This recent development could enhance the economic viability of a thermal solar tower, which can collect heat energy by focusing sunlight which can be reflected off thousands of mirrors.
A research team at the UC San Diego Jacobs School of Engineeringwas credited in the development of this special type of paint. Their work was described in two articles published in the Nano Energy journal.
Solar tower made possible with nano-particle materials
During the operation of a thermal solar tower, steam of molten salt is heated to extreme temperatures. This is done to help run steam turbines which in turn generate electricity.
Since the inside of a solar tower is painted, the efficiency will be adversely affected as the paint coat cracks or is peeled off the surface. The surface would then need to be repainted or completely replaced in order to restore full efficiency of the solar tower. As such, regular maintenance cost would have to be deducted from profits, not to mention the solar tower downtime during repairs.
This is primarily the reason why engineers initially began developing a special type of paint to cut maintenance costs and limit unproductive downtime. Engineers are also searching for ways to run the solar tower at higher operating temperatures and store heat to generate electricity at night.
Regular maintenance of previous solar tower materials a major cost
“Instead of 550 Celsius, they want to operate this at 750 Celsius,” said Sungho Jin, a professor at Jacobs School inCalifornia and an expert in mechanical and aerospace engineering.
“And at 750 degrees, things can get red hot. … We came up system compositions and a structure which makes the materials stable,” Jin added.
According to Jin, if engineers could rack up the thermal properties of the paint so that it can endure higher temperatures, this would mean a 30 per cent improvement in solar efficiency.
By using tiny, nano-sized particles, ranging from 10 nanometers to 10 micrometers, the engineers hope that this special paint will be able to absorb 90 per cent of approaching sunlight. Interestingly, the engineers named their invention the “black hole.”
New paint on solar tower means a 30% jump in solar efficiency
The research and development project was funded by the Sunshot Initiative of the Department of Energy. Their aim is to facilitate the development of solar energy technologies to help in increasing the efficiency of solar PV systems.
Jin’s team included two other engineering professors, Renkun Chen and Zhaowei Liu. All three are experts in functional materials engineering.
Their invention will definitely impact the solar energy industry since solar towers all over the world generate several gigawatts of solar generation capacity.
For instance, Carlsbad’s NRG Solar inaugurated the world’s largest concentrated solar plant in February, 2014. It is comprised of three solar towers that are designed to power 180,000 homes.
In order to facilitate the development of their invention, the three engineers are pursuing more funding by seeking private partners who will also help commercialize their technology.
