Ocean Thermal Energy
Conversion (OTEC)
Air Conditioning With Deep Seawater: A Cost-Effective Alternative An article by Dr. Joseph Van Ryzin, President and Tore Leraand, Ocean Engineer, Makai Ocean Engineering Inc. Published in Ocean Resources 2000, Sea Technology, September 1992. Deep, cold seawater has long been recognized as a valuable ocean energy resource. Over the past 20 years research and experimentation has been conducted on ocean thermal energy conversion (OTEC) and cold water mariculture. Out of this particular research effort, one clear economic winner emerged: seawater air conditioning.
Benefits of OTEC We can measure the value of an ocean thermal energy conversion (OTEC) plant and continued OTEC development by both its economic and noneconomic benefits.
Common Heritage Corporation The Common Heritage Corporation was established in 1990 by Dr. John P. Craven, for the purpose of developing environmentally sustainable ocean resources for the benefit of the Common Heritage. The Common Heritage was legally defined for the first time in the United Nations Treaty on the Law of the Sea, which came into force in 1994. The corporation is organized as a profit making corporation of the State of Hawaii, its mission is to establish self-sufficient environmentally, economically and culturally sustainable communities in coastal zones and islands having access to deep ocean water.
Environmentally Sustainable Air Conditioning/Industrial Cooling The single most effective measure for reducing carbon dioxide emissions on a global basis would be the substitution of deep ocean water air conditioning and industrial cooling wherever and whenever it is feasible. But 'hard headed' business persons who do not give a fig for 'global warming concerns' are economically 'soft headed' if, for profit making reasons, they do not install deep ocean water cooling systems whenever and wherever feasible. For once the "bootleggers and the ministers" can cooperate for the benefit of humanity. Here in 'cold hard print' is a paper from Makai Ocean Engineering Company that tells it like it is from an economic standpoint.
Hawaii Sea Grant Spurs Pacific Aquaculture When a Sea Grant program was established at the University of Hawaii in 1968, the aquaculture industry was virtually nonexistent in the state. Although the Hawaiian Islands have the oldest tradition of aquaculture in the United States, it was looked upon an artifact of an ancient Hawaiians. Few people outside the University of Hawaii Sea Grant program and the state's Anuenue Fisheries Research Center expected the economic impact that aquaculture would have less than three decades later. Hawaii Sea Grant also was one of the first to become involved in an exciting new venture: ocean thermal energy conversion (OTEC). OTEC utilizes a virtually limitless natural resource around the Hawaiian Islands: deep ocean water. This pure, cold, nutrient-rich and pathogen-free water is ideal for the culture of temperate fish and other marine sources of protein. Despite skepticism, Hawaii Sea Grant researchers effectively proved the concept in projects focused on two commercially valuable cold-water species (salmon and trout) and on growing nori, an algae popularly used in many island foods. Sea Grant was the first to show the potential of deep ocean water as a valuable resource.
History of OTEC and How it Works
Makai Ocean Engineering, Inc. Makai Ocean Engineering, Inc. was established in 1973 as a diversified ocean engineering and naval architecture company providing service in Hawaii and the Pacific. Today, Makai provides ocean engineering services world wide.
Natural Energy Laboratory of Hawaii Authority (NELHA) Located on 870 acres at Keahole Point, on the Big Island of Hawaii, our unique ocean science and technology park provides the resources, support and facilities for many innovative ocean-related businesses. Cold deep seawater pumped up from 2000 foot deep off Keahole Point is utilized to produce energy, desalinate water, grow lobsters and fish, produce algae and shellfish, grow cold climate fruit and vegetables in the tropics and much, much more.
NREL - Ocean Thermal Energy Conversion Information about OTEC from the National Renewable Energy Laboratory.
Ocean Energy Generating technologies for deriving electrical power from the ocean include tidal power, wave power, ocean thermal energy conversion, ocean currents, ocean winds and salinity gradients. Of these, the three most well-developed technologies are tidal power, wave power and ocean thermal energy conversion. Tidal power requires large tidal differences which, in the U.S., occur only in Maine and Alaska. Ocean thermal energy conversion is limited to tropical regions, such as Hawaii, and to a portion of the Atlantic coast. Wave energy has a more general application, with potential along the California coast. The western coastline has the highest wave potential in the U.S.; in California, the greatest potential is along the northern coast.
Ocean Energy Ocean energy systems produce power from either the movement of waves and tides or the temperature differences that exist in the ocean. Ocean energy topics include thermal energy conversion systems (closed-cycle, open-cycle, and hybrid), tidal power systems, and wave power systems.
Ocean Energy Systems - Energy Fact Sheet
Ocean Engineering, SOEST, U.Hawaii Alumni and MS Papers/Theses and PhD Dissertations. Many relating to ocean energy (waves energy and OTEC).
Ocean Thermal Energy Conversion (OTEC) Generates electricity by tapping the temperature difference in oceans between deep water and the warmer surface.
Ocean Thermal Energy Conversion (OTEC) The oceans of the Earth have a vast untapped energy resource in the temperature difference between warm surface waters and cold waters of the ocean depths. An OTEC plant has a very large-diameter cold-water intake pipe that stretches a mile or more down into the ocean and brings cold water to the surface.
Ocean Thermal Energy Converter A new Ocean Thermal Energy Conversion (OTEC) system which utilizes air as the working fluid, air bubbles as efficient heat exchangers between air and water, and sonic wave in two-phase media as the energy carrier in the thermodynamic cycle, directly transforming sonic wave energy into electrical energy. In the proposed OTEC system electric energy is generated by the oscillatory pipe wall deformation caused by the sonic wave. This deformation alters the width of a narrow gap between two ferromagnetic surfaces. Weak initial current creates a strong magnetic field in this gap. Oscillation of this gap width produces a variation of the magnetic flux, which is then used for inducing an electric current. This eliminates the mechanical losses associated with conventional OTEC systems. The estimated efficiency of the proposed OTEC system is 4%, compared to 2% obtainable from traditional OTEC systems. Even more significant is a drastic reduction in construction and maintenance cost due to reduced volume and absence of heat exchangers and rotating machinery.
Ocean Energy Technologies - Tapping into the Ocean's Vast Energy Resource For thousands of years, the ocean has provided people with food and transportation. Today, it's starting to provide us with another valuable resource--energy. Covering 70 percent of the Earth, the ocean is a gigantic solar collector that absorbs and stores heat. This heat can be extracted and used to generate electricity. The ocean also contains vast amounts of energy in the form of waves, tides and currents. To produce power, the motion of these waves, tides and currents is used to drive a turbine-generator similar to those found in hydropower plants.
Ocean Thermal Energy Conversion (OTEC) - What Is It? A fact sheet about ocean thermal energy conversion and its use in Hawaii.
OTEC - Closed Cycle vs. Open Cycle A brief discussion of the relative merits of each cycle.
Plant Design and Location Commercial ocean thermal energy conversion (OTEC) plants must be located in an environment that is stable enough for efficient system operation. The temperature of the warm surface seawater must differ about 20°C (36°F) from that of the cold deep water that is no more than about 1000 meters (3280 feet) below the surface. The natural ocean thermal gradient necessary for OTEC operation is generally found between latitudes 20 deg N and 20 deg S. Within this tropical zone are portions of two industrial nations—the United States and Australia—as well as 29 territories and 66 developing nations. Of all these possible sites, tropical islands with growing power requirements and a dependence on expensive imported oil are the most likely areas for OTEC development.
Renewable Ocean Resources EcoNet's links to renewable ocean resources.
Sea Power An article by Mariette DiChristina. The world's largest solar collector absorbs an awesome amount of the sun's energy: equal to 37 trillion kilowatts annually - or 4,000 times the amount of electricity used by all humans on the planet. A typical square mile of that collector - otherwise known as the surface waters of Earth's vast oceans - contains more energy than 7,000 barrels of oil.
Sea Water Air Conditioning (SWAC) Outline They began this effort with the intent of laying out the requirements, equipment, and capabilities of a sea water air conditioning system (SWAC) for the Aquarius Rising site on St. Croix.
Tapping Power From The Oceans A brief article on OTEC by Robert Frenay.
The First Millennial Foundation The Foundation's first colony is being built in cyberspace. The Millennial Project book details how we can build toward the ultimate human destiny of leaving planet Earth and colonizing space. It is a project that will occupy us completely for the next thousand years. "The Millennial Project has the modest sub-title "Colonizing the Galaxy in 8 Easy Steps," and that's what it's all about-though some readers may challenge the author's definition of 'easy'. However, even those who have no extra-terrestrial ambitions will be fascinated by his projects for sea-farming, floating cities and underwater habitats. Like most of the book's concepts, these are illustrated by dramatic and often strikingly beautiful colour plates" (Arthur C. Clarke)
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Ocean Thermal Energy Conversion (OTEC) | Wave Energy
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