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John Piña Craven is a highly intelligent man of about 80 years who seems to think that cold water can make many people’s life better. Lower a siphon into the frigid depths of the ocean , and with the chilled bounty one can produce electricity, drinkable water, cheap air refrigeration, and— according to Craven— more fertile soil and healthier bodies.
Craven’s claims, however preposterous they may seem, warrant some attention. He has proven himself able and intelligent, and he can demonstrate his cold-water results, at least on a small scale. He has a PhD in ocean engineering, and he was the chief scientist for the US Navy’s Special Projects Office during a decent chunk of the cold war. There, he played an important role in the development of the Polaris missile platform, one of the most complex defense systems ever devised. In fact, much modern ocean technology has its roots in the the projects he oversaw for the Navy.
Some of Craven’s theories are based on known scientific principles… Ocean Thermal Energy Conversion (OTEC) was first dreamt up by a French physicist named Jacques Arsene d’Arsonval in 1881. When heat is exchanged between cold water siphoned from the ocean bottom and warm water drawn from the top, the transfer can be captured and converted to electricity. But even today, the technology rarely sees efficiency greater than three percent. But three percent is more than zero percent, and many researchers are working on improving the efficiency.
There are other benefits to the system as well… the cold water system also generates clean drinking water, fresh irrigation water, and refrigeration. Since last year, the city of Toronto, Canada has been proving the concept by using cold water from deep in Toronto lake Lake Ontario to air condition their downtown buildings and provide chilled drinking water.
From the Wired article:
Running the frigid pipes through heat exchangers produces unlimited air-conditioning that costs almost nothing. Draining their sweat yields an endless supply of freshwater for drinking and irrigation. The cold water also creates a temperature difference between root and fruit that Craven believes speeds growth. And by turning the flow on and off, Craven has found he can further accelerate the plants’ growth cycle by forcing them in and out of dormancy – he can get three crops of grapes a year and pineapples in eight months instead of the usual 18. Feeding some of the water through a contraption Craven calls a hurricane tower generates clean electricity. “What the world doesn’t understand,” says Craven, still zigzagging through the parking lot, “is that what we don’t have enough of is cold, not heat.”
A bit unorthodox perhaps, but thought-provoking. As Sylvia Earle, former director of the US National Oceanic & Atmospheric Administration (NOAA) put it, “Craven is not always right, but he’s always worth listening to.”