NASA, U.S. Navy and university researchers have successfully demonstrated the first robotic underwater vehicle to be powered entirely by natural, renewable, ocean thermal energy.
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"People have long dreamed of a machine that produces more energy than it consumes and runs indefinitely," said Jack Jones, a JPL principal engineer and SOLO-TREC co-principal investigator. "While not a true perpetual motion machine, since we actually consume some environmental energy, the prototype system demonstrated by JPL and its partners can continuously monitor the ocean without a limit on its lifetime imposed by energy supply."
"Most of Earth is covered by ocean, yet we know less about the ocean than we do about the surface of some planets," said Yi Chao, a JPL principal scientist and SOLO-TREC principal investigator. "This technology to harvest energy from the ocean will have huge implications for how we can measure and monitor the ocean and its influence on climate."
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So far, SOLO-TREC has completed more than 300 dives from the ocean surface to a depth of 500 meters (1,640 feet). Its thermal recharging engine produced about 1.7 watt-hours, or 6,100 joules, of energy per dive, enough electricity to operate the vehicle's science instruments, GPS receiver, communications device and buoyancy-control pump.