CN-J Technology (CN-JT), a Taiwan-based venture firm, showed a solar tracking device that does not use a motor and hardly consumes electricity for tracking the sun.
The solar tracking device was exhibited at the Photonics Festival in Taiwan, which took place from June 19 to 21, 2012, in Taipei, Taiwan.
Photovoltaic (PV) generation systems that track the sun can generate a large amount of electricity but consume electricity for the tracking. And the new solar tracking device can almost eliminate the power consumption, CN-JT said.
The principle used for the tracking mechanism of the device can be described as a balance having weights whose heaviness changes depending on the amount of solar light. Specifically, a black cylinder filled with fluorocarbon refrigerant is attached to each of the two ends of the board on which PV panels are placed.
The cylinder is equipped with a temperature sensor and a tube and connected to a piston that is similar to a piston used for a hydraulic system. When the piston moves, the orientation of the panel changes.
If sunlight drops on the solar tracking device when the panel is not facing the sun, one cylinder (cylinder A) receives a large amount of sunlight while the other (cylinder B) hardly receives sunlight. Then, because of the difference in the amount of received sunlight, the two cylinders have different temperatures and chlorofluorocarbon's pressures. The temperature sensor detects the temperature difference and controls a regulator so that the orientation of the panel is changed by using the pressure difference to move the piston.
If the orientation of the panel changes too much and the cylinder B receives more sunlight than the cylinder A, the piston moves in the opposite way. When the panel is facing the sun, the two cylinders receive an equal amount of sunlight. Therefore, there is no temperature difference, and the piston does not move. In this way, the panel always faces the sun.
"Though the sensor consumes electricity, it is much smaller than the power consumption of traditional solar tracking devices using a motor," CN-JT said.
The cylinders have to be detached from the board biennially for maintenance such as checking the sensor, refilling them with gas, etc.
CN-JT developed the solar tracking device in 2010 and received a gold medal at iENA 2010, an exhibition about inventions, which took place in October 2010 in Nuremberg, Germany.