How two brothers from Kolkata became a marine robotics manufacturer — a deep dive
Telegraph | 11 May 2026
Humans first set sail to traverse the oceans to inhabit Australia. The continents were much closer then, still seas and rivers have always been the backbone of a civilisation. Today, one does not need to build a raft to cross the Hooghly river, but surely does need modern marine equipment to pinpoint an underwater object on an open body of water.
Realising this need, two brothers, Swarnav Banerjee and Rishav Banerjee founded Banergy, a marine robotics manufacturing company.
Commenting on the name of the company, Swarnav said, “My grandfather used to say ‘Swarnav Banerjee — full of energy’, so my younger brother Rishav created the name from an amalgamation of two (Banerjee and energy).”
Banergy is the only one of its kind from Bengal, claim the brothers, manufacturing marine robotics in their factories in Bankura and Balasore.
“We encourage other marine enthusiasts to use our blueprints. Even if they build an exact replica we have no problem, because we want to build an ecosystem of marine robotics in Bengal,” said Swarnav.
Banergy manufactures remotely operated vehicles (ROVs) and unmanned surface vessels (USVs). These are marine robots which have an array of uses in rivers and oceans.
Both the brothers have lived in the US to study and work as engineers; the elder one in electrical, the younger one in mechanical. But they never wanted to settle there.
“We always had a plan to come back to our home country. I was 10 years older than him. When I studied electrical engineering, I understood that an electro-mechanical team work is needed. So, I pushed him to study mechanical engineering,” said Swarnav.
Along with Rahul Pareek, the marketing head for Banergy, all three are serious divers. They are not just manufacturers, but understand the real-life problems people face underwater.
“We are very intimate with the product and the environment. We have a lot of personal experience. The problem that people are facing can’t be understood in a closed room, it needs divers,” said Banerjee.
The National Institute of Oceanography, Indian Railways, the National Disaster Response Forces and the Kolkata Police have all been impressed by Banergy and their sub-marine robotics. BROV X (Banergy Underwater Remotely Operated Vehicle), BUSV X (Banergy Unmanned Surface Vessel) help in rescue operations, river-bed mapping, and locating damages in the bridges over rivers, among various other uses.
Talking about one such operation, the brothers informed how they found the location of equipment worth Rs 40 lakh that an ecological company lost in the Hooghly. The company head told the brothers they had planned a 72-hour operation.
“We found the equipment within five hours, by locating it with sonar from our robots,” said Banerjee.
The boat and the marine drone use one-dimensional sonar to essentially capture ultrasonography images, the team then looks for anomalies in the river-bed to pinpoint the object.
Divers can then accurately dive in that location to retrieve the object. The marine robots from Banergy also have mechanical arms which can pull objects of various weight brackets.
When asked about what else they have found at sea, Swarnav said, “When diving with our robots, I never know what I am going to find underwater. When I dived in Hawaii, the fish, turtles, coral reefs were my treasure. When my robots dive in the Ganga, I find all sorts of sunken objects — from boats to statues. If I am given the opportunity, I want to scan the entire Gangetic route from Krishnanagar to Diamond Harbour, to see what all secrets the river holds,” said Swarnav.
Rishav had a very intriguing answer to this. “When I was in Los Angeles, we used to see the Space X missions. The company has a policy that they would buy all their rocket parts that landed in the ocean for $8,000. So me and two of my friends used to try and guess where the rocket parts landed. A boat trip with friends thus would mean a cash prize. This was my treasure hunt,” said Rishav.
Banergy also makes a diver propulsion vehicle called SHARK DPV which is essentially a scooter underwater. It can be used by everyone from professionals to casual swimmers.