John Craven’s Experimentation with Cold Ocean Water to Increase Agricultural Productivity


One day not so long ago in the Cafe at Arcosanti,  Darina T was questioning the wisdom of putting ice in the plants that landscape manager Ron Chandler had confessed to doing on occasion. I responded that actually my research led me to believe that its not so crazy. It got me to think of a outrageous story about how a former military seaman become a leading advocate for an appropriate technology called Ocean Thermal Energy Conversion that also included research on using cold ocean water to cool plant roots at the Natural Energy Laboratory of Hawaii.

John Pina Craven was never a ordinary military man – portrayed as a lover of the sea and all that’s in it – he became known for his role in the developing the Polaris Missile System. A man of many talents, during the Carter Admin, he served as director of the International Law of the Sea Institute. A key realization in his life was this idea of Common Heritage – that we must better learn how to harness the energy of the sea to develop sustainable energy and life support systems – for the benefit of all of humanity.

This story is one of hope but also of tragedy – a common story told all across the planet as many similar visionaries still struggle with their ideas of a future worth living for humanity.  People like Paolo Soleri, Doug Engelbart, George Chan, John Todd and John Craven were people definitely ahead of their time. They sought through their work to follow in the mold of Bucky Fuller and EF Schumacher: – to design systems that through their holistic synergistic interactions could transform humanity to a more prosperous and sustainable trajectory of learning how to use technology appropriately for the common benefit of all humanity and operating in harmony and not in opposition to the planet.

Yet in the midst of political correctness and the inability to stand up against it in any kind of viable way, these visionaries still struggle even in this supposed age of “Green Tech”. Possibly they will die with out their vision being realized and possibly it is due to their intransigance or some fatal flaw within them in combination with a massive social resistance towards real social change and innovation towards ecological and social sustainability.

Craven sought to portray the ocean as a massive huge energy engine. If tapped he believed it could unleash massive amounts of energy that could dramatically change the socioeconomic dynamics of many island nations and tropical regions which are now mired in poverty. He had a soft spot for these parts of the world because he was a seaman who lived his life in Hawaii. Working at the federal research lab on the Big Island, he began experimenting with the idea that energy could be harness from the sea by taking advantage of the difference T (carnot) between warm surface water and cold 2000 ft below sea level sea water. The systems he developed were highly integrated and holistic. They included the use of ocean water to cool buildings, produce electricity, and with the case of agriculture there seemed to be some evidence of how using cold ocean water to cool plant roots could increase production in tropical environments at least. It seemed like a no brainer really. Water is used by plants for several reasons to bring in nutrients (nutrients are best assimilated by plants through a high enough/optimized moisture content), and for reasons similar to humans and animals – to replentish water supplies lost via evaporation and excretions. Plants don’t excrete but they do shed dead leaves that have water in them, some fruit or release body mass through seeds and probably the biggest water loss is by water loss through transpiration. Maybe that’s the key to explaining the reason why plants do better in cool root conditions is the cooling effect it creates for the plants in high heat conditions.

However Craven says that when the root structure or pack of the plants is cool then the water for the plants is at a more ideal temperature for transferring of nutrients. He says that the difference T between the plant leaves and the roots is conducive to moving nutrients. What’s also notable is the cool ocean water going through the plastic pipes leads to the creation of the dew. This effect apparently reduces or in some cases eliminates the need for irrigation of the plants.

Here is a link to a video which explains Cold Water Agriculture that includes an appearance by well known ocean scientist Sylvia Earle. Whats interesting to look at is that if Sylvia was excited enough about this technology to appear in a video with him and work with his company but not use her considerable reputation as a Time Hero of the Planet and TED Fellow.

While this was done using cold ocean water from 2000 feet below sea level its possible that similar results could be achieved using cold ground/well water. Arcosanti because of its hot climate (and not just because of its lack of water, plethora of pests and intense sunlight) could be a ideal environment for applying a experiment like what John Craven has done. And what’s remarkable to consider is how it seems to be a very or relatively low cost solution that significantly increase production and help make agriculture more feasible at Arcosanti. it could be a game changer that might complement a serious agriculture production program there.

Over the years he gained as following of people who were attracted to his eclectic if not eccentric personality –  like Soleri and others. His struggle was not due to lack of media coverage The New York Times and Wired both featured articles on his work that were very laudatory. In 2006 as he was getting the media coverage most recently in Wired, I briefly was part of communications between George Chan and his several officers in his company Common Heritage Corp. During this time I was included in a few emails between George Chan and Common Heritage Corp CEO/executive Charlotte Vick as they discussed the possibility of combining their designs (Chan’s Integrated Farming & Waste Management System and Craven’s Ocean Thermal Energy Conversion) into one system to be deployed in Saipan. Common Heritage was waiting for money to be allocated via a reasonably sized DoE grant which is referenced in the Wired Magazine article. The money never came and possibly the larger venture capital money was predicated on that initial money because it seems that never came either.

However the cause for further research of his work still needs to be explored. I believe the case for doing further research on the Cold Water Agriculture and particularly in relation to inhospitable growing environments like the climate where Arcosanti is located is compelling.

References & Notes

  1. Rick Nelson had a discussion with Jack Davidison who was then CEO of Common Heritage in 2001 regarding collaboration on the development of Cold Water Agriculture.
  2. ZERI NM had a meeting with John Craven that led to the posting of this article but never seemed to lead to any modification of his approach for NM.

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