In Spain, Andalusia, near Seville, a 100 meters high tower is surrounded by gargantuan mirrors, that run around the tower in concentric circles. These rippling mirrors can track sunlight throughout the day and reflect it on to the tower; in turn, it is converted into solar energy. The energy created at the plant is sufficient enough to power 6000 homes. The name of the site is PS10.
There are few such CSP (Concentrated Solar Power) sites in the world. The Proponents of CSP state that technology has the potential to generate energy for the entire United States. However, land and large quantities of sunlight are necessary for its application.
MIT has designed a CSP plant that uses less land and can concentrate more sunlight in collaboration with RWTH Aachen University in Germany. This design reduces the carbon footprint of a solar plant by 20% and increases its energy-producing potential. It also allows for a more compact layout and lowers the heliostat shading and blocking from neighbouring mirrors. The researchers of the project have already filed for a patent. However, the concentric circles around the mirror result in higher shading, reducing the amount of sunlight reflected in the tower.
The research team tried to overcome this obstacle by looking for alternative designs for the arrangement of mirrors. The heliostat layout was played with. Mirrors were placed close together, which resulted in a more compact design without compromising the mirrors’ ability to reflect sunlight towards the tower. The new design echoes the pattern of a sunflower. The florets in a sunflower are laid out in a spiralling pattern known as a Fermat spiral. The florets are placed at a golden angle of 137 degrees concerning its neighbouring floret. This design reduces the land requirement by 20% and also minimizes shading and blocking. The innovative design would also result in huge cost savings.