A solar tracker is a device that orients a payload toward the Sun. Payloads are usually solar panels, parabolic troughs, fresnel reflectors, lenses or the mirrors of a heliostat.Trackers direct solar panels or modules toward the sun. These devices change their orientation throughout the day to follow the sun’s path to maximize energy capture. In photovoltaic systems, trackers help minimize the angle of incidence (the angle that a ray of light makes with a line perpendicular to the surface) between the incoming light and the panel, which increases the amount of energy the installation produces. Concentrated solar photovoltaics and concentrated solar thermal have optics that directly accept sunlight, so solar trackers must be angled correctly to collect energy. All concentrated solar systems have trackers because the systems do not produce energy unless directed correctly toward the sun.
Single-axis solar trackers rotate on one axis moving back and forth in a single direction. Different types of single-axis trackers include horizontal, vertical, tilted, and polar aligned, which rotate as the names imply. Dual-axis trackers continually face the sun because they can move in two different directions. Types include tip-tilt and azimuth-altitude. Dual-axis tracking is typically used to orient a mirror and redirect sunlight along a fixed axis towards a stationary receiver. Because these trackers follow the sun vertically and horizontally they help obtain maximum solar energy generation. There are also several methods of driving solar trackers. Passive trackers move from a compressed gas fluid driven to one side or the other. Motors and gear trains direct active solar trackers by means of a controller that responds to the sun’s direction. Finally, a chronological tracker counteracts the Earth’s rotation by turning in the opposite direction.
Selecting a solar tracker depends on system size, electric rates, land constraints, government incentives, latitude and weather. Utility-scale and large projects usually use horizontal single-axis solar trackers, while dual-axis trackers are mostly used in smaller residential applications and locations with high government Feed-In-Tariffs. Vertical-axis trackers are suitable for high latitudes because of their fixed or adjustable angles. Marking its entry into the Indian solar market, Germany-based tracker manufacturer, Deger Energie GmbH & Co. KG has teamed up with Kavitsu Robotronix Pvt Ltd to create a new joint venture company, Kavitsu Deger Pvt Ltd.
Under the partnership, the two will set up a PV tracker manufacturing facility in Satara, Maharashtra. A spokesperson tells pv magazine that 10,000 units per year will be manufactured initially, which will be capable of serving 200 MW of solar farm capacity. The plan is to double this in 2020.
While 70% of production will be focused on single axis trackers, the remaining 30% will comprise dual axis trackers, says the spokesperson. They add that the basic manufacturing infrastructure is already in place. Between €5 million and €10 million will be invested in the venture, says the spokesperson, although they declined to say by whom. The Indian Government will provide additional subsidies, they add, although again, no further details were divulged.
Regarding the necessary production equipment, the spokesperson says the electronics will come from Germany, while the rest will be manufactured in India. “Production Equipment necessary for Indian Operations will be procured by new Joint Venture Company Kavitsu Deger Pvt. Ltd,” they say. The first trackers are set to come off the production line by January 2019. Kavitsu Deger aims to capture a 50% share of the Indian tracker market. The remaining products will be sold to other Asian markets.
The Kavitsu Group has a further four manufacturing facilities in Satara, producing Industrial Gear Boxes, Electric Motors & Slew Bearing. Deger has offices in Spain, Greece, Australia, South Africa, Canada, Egypt and Turkey. Meanwhile, it has manufacturing facilities in Germany, Turkey, Canada and South Africa. In the September edition of pv magazine, Deger talked tracking technology, the industry, and its own journey of innovation. At the time, it said it offered four single-axis DEGERtrackers and six dual-axis DEGERtrackers. A further iteration of a single-axis tracking systems was expected to follow later that year.