Invention:
This technology is a twisting heliostat that automatically adjusts its reflector’s shape throughout the day to adapt to changes in the sun’s relative position to the heliostat field. It uses closed loop tracking to ensure that that light reflected from each twisted heliostat is centered on a target point. This design allows for higher concentration of solar energy with better efficiency than conventional heliostats with a fixed shape. Researchers developed and tested a prototype to validate the twisting heliostat design.
Background:
Heliostats are reflectors placed on rotating mounts capable of reflecting incoming sunlight to a target. Fields of heliostats are used to reflect sunlight towards a central point, concentrating the solar power reaching the field at that single spot as a method of solar energy generation. For each heliostat in a heliostat field to achieve the highest possible concentration, its reflector must be in a toroid shape. The ideal side lengths of this toroid vary depending on the angle of incident sunlight.
Standard heliostats are capable of dual-axis rotation to continuously reflect the sun’s rays to a target point but have fixed reflector shapes that cannot be changed to reflect changes in the angle of incident sunlight throughout the day. Additionally, many current heliostats operate on open loop tracking systems in which the ideal heliostat angle is calculated based on the heliostat’s location on Earth and the relative positions of the Earth and Sun. While functional, these systems can’t achieve a high level of precision since they can’t account for uneven ground conditions or heliostat flaws and irregularities. By automatically changing reflector shape and by utilizing a closed-loop, sensor-based tracking system, this invention achieves higher accuracy and efficiency than has been previously possible.
Applications:
- Heliostats
- Concentrated solar power
- Renewable energy
Advantages:
- Automatic shape adjustment
- Adjustable reflector shape
- High accuracy orientation
- Closed loop tracking system
- More efficient
- More powerful
