Into the Deep
There’s a glut of research on climate change. Seemingly every day some new study comes out demonstrating the latest scientific understanding of changes to the Earth’s systems. But the foundation of much research of this type is measurement, and there are, of course, severe limits to what can be measured.
Improvements to our measurement abilities goes a long way towards improving and expanding climate change research. Which is why a new technology that fuels ocean robot exploration has been getting some attention recently. The oceans remain one of the least explored areas of the planet — some 95 percent of the underwater world remains a mystery — yet they account for 71 percent of the Earth’s surface. If we don’t know the oceans, we don’t really know the Earth.
That may be changing. Researchers at NASA’s Jet Propulsion Laboratory in Pasadena and the Scripps Institution of Oceanography at the University of California, San Diego just completed a three month study of a new ocean exploration vehicle that uses the thermal differences in ocean temperature as a renewable energy source. That means researchers can use a device to “continuously monitor the ocean without a limit on its lifetime imposed by energy supply,” according to JPL engineer Jack Jones, a co-principal investigator in SOLO-TREC.
Ocean monitoring devices have been previously limited by battery-powered underwater vehicles (after all, solar and wind recharging are not going to work underwater), leaving researchers unable to obtain long term monitoring of the climate and other forms of marine life studies and exploration. The new 183-pound devices have a waxy substance that expands and contracts as thermal temperatures change and in so doing pressurizes oil that drives a hydraulic motor to make electricity and recharge batteries. The renewable energy system produces about 1.6 Watt-hours of power for a surface to 500-meter dive while operating on-board sensors, a GPS receiver, and a communication device.
It’s hard to imagine there not being more applications for this kind of thermal-driven ocean propulsion. Apparently, the U.S. Navy has taken note on how it can apply the technique to its submersible vehicles.
– Alison Hawkes