If you want to study what lurks in the deepest, darkest parts of the ocean, an underwater drone system is your best choice. A California-based startup called Seatrec should soon power such systems by taking advantage of the ocean’s changing temperatures.
So, before going deeper into the topic, what exactly are underwater drones? Typically, they are torpedo-shaped autonomous underwater vehicles (AUVs) that utilize buoyancy to propel themselves. These drones have proven to be a game-changer for studying the world’s oceans; everything from shipwreck hunting to exploring the deepest, darkest parts of the ocean floor has found the use for underwater drones – and the money and time they save. Imagine the use of underwater drones to scan for many sites simultaneously, eliminating the need for another expensive voyage.
Even Jim Delgado, senior vice president at underwater archeology firm SEARCH, believes that this innovation is proof that we’re in a whole new era of exploration, discovery, and understanding.
However, any drone requires power to function, and the current ways of keeping AUVs running have turned many of these machines into “disposable” devices, as researchers lack the resources and technologies to retrieve them once the mission is over. That could mean more Li-Ion batteries in the sea, where they can pollute and leak toxic chemicals.
That’s Where The Seatrec System Comes In
The startup claims that its SL1 Thermal Energy Harvesting System can already help save researchers the time and money of using robotic underwater drones for oceanographic exploration. The startup is working its system to work with autonomous underwater drones. And it has partnered with Northrop Grumman to develop an underwater recharging station for oceangoing drones that incorporates the defense giant’s self-insulating electrical connectors capable of operating while submerged.
Underwater Drone – How it Works
Based on a concept developed by Henry Stommel, the system utilizes phase-change materials. The energy-harvesting system works by taking advantage of certain substances’ transition from solid-to-liquid and liquid-to-gas phases when heated. In other words, the company harnesses the pressure changes to generate electricity in the most eco-friendly manner possible.
To make phase changes happen, the system taps the temperature differences between colder water at the depths and warmer water at the surface. Even a relatively simple robotic probe can generate electricity by changing its buoyancy to either shift or float in the ocean.
In the case of Seatrec’s underwater drone, they use paraffin wax-based material inside an aluminum cylinder. And running lengthwise through the center of the cylinder is a rubber tube filled with hydraulic oil.
When the underwater drone is gliding in the cooler part of the ocean, the wax stays solid. As the glider climbs into warmer areas, the wax begins to melt. The wax then becomes a liquid and pushes on the tube, forcing the hydraulic oil thru a generator.
The high-pressure oil spins the generator, creating electricity for the batteries. When the drone goes back into the abyss, the wax solidifies, and the oil flows back in.
Seatrec hopes that this breakthrough could support commercial ventures such as the aquaculture and deep-sea mining industries, although the latter might be controversial due to their environmental impacts.
In 2002, Seatrec received an award for its revolutionary work in creating green energy solutions for persistent oceanographic studies to power profiling floats and underwater drones. Competitors were asked to submit their ideas and prototypes to integrate ocean observing platforms with marine energy systems.
Seatrec designs and manufactures energy harvesting systems to generate electricity from the ocean. This innovation can be used to power different machines and equipment in a cost-effective and eco-friendly way possible. Incorporated in 2016, it originated from NASA’s Jet Propulsion Lab, California Institute of Technology to provide power for remote locations. It’s headquartered in Monrovia, CA. You can visit their site at https://seatrec.com/.