Renkube, a Bengaluru-based start-up, is gearing up to unveil its proprietary ‘motion-free optical tracker’ technology in the solar energy market. The technology has the potential to revolutionise the solar energy industry.
The conventional tracker-based system to keep the solar panels always facing the sun — as the sun moves from east to west across the firmament — is not a great one as the mechanical trackers on the system, with motors and many moving parts, makes maintenance a headache.
But, Renkube’s trackers are motionless. “The tracking capability is embedded inside the glass,” says Dr Lakshmi Santhanam, Co-Founder and CEO, Renkube.
The heart of the system is an AI-based proprietary software, with more than 2,00,000 lines of code. With the help of the software, grooved patterns are created on glass to make it behave like a prism. Once the design is done, the glass is manufactured and assembled with the solar panels.
The critical part of the fixture is the ‘grooving’ on the glass. Dr Santhanam, a software professional who has a PhD in network security from the University of Cincinnati, US, says the company applied the team’s expertise in machine learning algorithms to design the grooves in a manner that capture more sunlight — the grooves impart certain geometric design on the glass, which enables it to harvest and redirect sunlight.
The team comprises the Founder, Balaji Lakshmikanth Bangolae, the lead inventor of the motion-free tracker technology and three co-founders—Janardhana Vittalrao Kshirsagar, who has a PhD in microwave communications and Deepika Gopal, who has a Masters in Computer Science from the University of California, San Diego.
The team’s collective expertise has come up with a unique geometry on glass that can bend the path of light to make it fall on the solar panels. These light-redirecting ‘prisms’ are assembled on the solar panels at a module manufacturing plant. Once fixed, there is no tilting or adjusting needed, and the panels will generate more energy throughout the year. Conventional mechanical trackers have motors, actuators, sensors, etc, but Renkube’s system is just a special sheet of glass. They can be cleaned with water.
The architecture has been piloted for a year in Bengaluru and the company is now preparing to get the product contract-manufactured. The company has tied-up with Swelect Energy for using their module plant in Coimbatore for producing the panels.
Dr Santhanam told Quantum that the system would cost 5-10 per cent more than a tracker-less solar plant, but generation will be higher by at least 20 per cent. The company reckons that a 100 MW solar plant would cost $5 million more with Renkube’s products, but the additional cost will be paid back in two years.
However, Renkube’s system would need to be manufactured right when the modules are produced — no retrofit is possible. At present, the grooved glass is manufactured in Singapore and brought to the Coimbatore module plant. However, Dr Santhanam sees the scope for further cost reduction if the glass could be locally-produced. For that, Renkube is in talks with Saint Gobain, Chennai, for making the glass. The glass does not have to be special; a regular, tempered borosilicate glass will be fine, says Santhanam. Logistics is a big cost driver as the imported glass would need to be packed and shipped with extra care and costs.
The product could be further customised for rooftops, building facades and balcony windows, says Santhanam.
The start-up is pitching Renkube for agro-photovoltaic—where the solar panels are put up at a height, allowing regular farming to be done on the ground below. A typical agro-PV lets about half of the land for cropping, but Rekube’s redirecting prisms sends the excess sunlight to the ground below. The panels are mounted so high that tractors can ply below them, notes Santhanam.