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Ocean Thermal Energy Conversion (OTEC) Programmatic Environmental Analysis: Volume 1

Description: This programmatic environmental analysis is an initial assessment of OTEC technology considering development, demonstration and commercialization; it is concluded that the OTEC development program should continue because the development, demonstration, and commercialization on a single-plant deployment basis should not present significant environmental impacts. However, several areas within the OTEC program require further investigation in order to assess the potential for environmental impacts from OTEC operation, particularly in large-scale deployments and in defining alternatives to closed-cycle biofouling control: (1) Larger-scale deployments of OTEC clusters or parks require further investigations in order to assess optimal platform siting distances necessary to minimize adverse environmental impacts. (2) The deployment and operation of the preoperational platform (OTEC-1) and future demonstration platforms must be carefully monitored to refine environmental assessment predictions, and to provide design modifications which may mitigate or reduce environmental impacts for larger-scale operations. These platforms will provide a valuable opportunity to fully evaluate the intake and discharge configurations, biofouling control methods, and both short-term and long-term environmental effects associated with platform operations. (3) Successful development of OTEC technology to use the maximal resource capabilities and to minimize environmental effects will require a concerted environmental management program, encompassing many different disciplines and environmental specialties.
Date: January 1980
Creator: Sands, M. Dale
Partner: UNT Libraries Government Documents Department

COMPARISON OF NUTRIENT DATA FROM FOUR POTENTIAL OTEC SITES

Description: An in-progress assessment of nutrient chemical data (phosphate, nitrate, nitrite, and silicate) from four potential OTEC sites (Puerto Rico, the Gulf of Mexico, Hawaii, and the South Atlantic) show reasonable comparison with archival data. At this time sufficient data is available only at the Tampa site (Gulf of Mexico) to discern seasonal variations which show an influx of nutrient-rich water in February, which decreases with time to a minimum in December. Results show a greater potential for stimulation of primary productivity at the Hawaii site than in the northern Gulf of Mexico due to the discharge of the cold water pipe into the photic zone.
Date: June 1, 1979
Creator: Quinby-Hung, M.S.
Partner: UNT Libraries Government Documents Department

ENVIRONMENTAL MONITORING AND ASSESSMENT PROGRAM AT POTENTIAL OTEC SITES

Description: Ecologically sound operations of projected Ocean Thermal Energy Conversion (OTEC) plants can be insured by careful attention to the marine environment during the design phase. this requires quality information from regions of potential OTEC interest, coordinated with required assessment studies to insure legal compliance. Currently, preliminary or actual surveys and laboratory studies are being conducted in the waters of Puerto Rico, the Gulf of Mexico, Hawaii, and Guam for potential moored or seacoast OTEC plants and in the equatorial South Atlantic for proposed plant-ship operations to provide such benchmark and baseline data. These data plus existing archival information can be used to model effects of OTEC operations based on projected design schemes. Four major areas of concerns (1) redistribution of oceanic properties, (2) chemical pollution, (3) structural effects, and (4) socio-legal-economic; and 11 key issues associated with OTEC deployment and operation have been identified. In general mitigating strategies can be used to alleviate many deleterious environmental effects of operational problems as biostimulation, outgassing, etc. Various assessment research studies on toxicity, biocide releases, etc., are under way or are planned to investigate areas where no clear mitigating strategy is available. Data from the monitoring and assessment programs is being integrated into a series of environmental compliance documents including a comprehensive programmatic environmental impact assessment.
Date: June 1, 1979
Creator: Wilde, P.
Partner: UNT Libraries Government Documents Department

Renewable Ocean Energy Sources: Part 1 - Ocean Thermal Energy Conversion

Description: A report in a series by the Office of Technology Assessment (OTA) considering renewable ocean energy sources as a possible energy supply. This report focuses on ocean thermal energy conversion and analyzes the feasibility of using it and evaluates current research on the topic (p. iii).
Date: May 1978
Creator: United States. Congress. Office of Technology Assessment.
Partner: UNT Libraries Government Documents Department

Ocean Thermal Energy Conversion Life Cycle Cost Assessment, Final Technical Report, 30 May 2012

Description: The Ocean Thermal Energy Conversion (OTEC) Life Cycle Cost Assessment (OLCCA) is a study performed by members of the Lockheed Martin (LM) OTEC Team under funding from the Department of Energy (DOE), Award No. DE-EE0002663, dated 01/01/2010. OLCCA objectives are to estimate procurement, operations and maintenance, and overhaul costs for two types of OTEC plants: -Plants moored to the sea floor where the electricity produced by the OTEC plant is directly connected to the grid ashore via a marine power cable (Grid Connected OTEC plants) -Open-ocean grazing OTEC plant-ships producing an energy carrier that is transported to designated ports (Energy Carrier OTEC plants) Costs are developed using the concept of levelized cost of energy established by DOE for use in comparing electricity costs from various generating systems. One area of system costs that had not been developed in detail prior to this analysis was the operations and sustainment (O&S) cost for both types of OTEC plants. Procurement costs, generally referred to as capital expense and O&S costs (operations and maintenance (O&M) costs plus overhaul and replacement costs), are assessed over the 30 year operational life of the plants and an annual annuity calculated to achieve a levelized cost (constant across entire plant life). Dividing this levelized cost by the average annual energy production results in a levelized cost of electricity, or LCOE, for the OTEC plants. Technical and production efficiency enhancements that could result in a lower value of the OTEC LCOE were also explored. The thermal OTEC resource for Oahu, Hawai’i and projected build out plan were developed. The estimate of the OTEC resource and LCOE values for the planned OTEC systems enable this information to be displayed as energy supplied versus levelized cost of the supplied energy; this curve is referred to as an Energy Supply Curve. The ...
Date: June 30, 2012
Creator: Martel, Laura; Smith, Paul; Rizea, Steven; Van Ryzin, Joe; Morgan, Charles; Noland, Gary et al.
Partner: UNT Libraries Government Documents Department

A Study of the Macrozooplankton within the Samples Taken at theMobile Site from November 1977 through November 1978:A Data Report of theLawrence Berkeley Laboratory

Description: This report brings together the results of a re-examination of zooplankton samples from the Mobile OTEC site (29{sup o}N-88{sup o}W) in the northern Gulf of Mexico for macrozooplankton larger than 15 mm. Five cruises were made to the Mobile OTEC site aboard the R/V Virginia Key. Cruise dates were: 17-20 November 1977; 27 February-2 March 1978; 9-17 June 1978; 15-24 August 1978; and 21 October-3 November 1978.
Date: November 1, 1981
Creator: Steen, John & Gunter, Gordon
Partner: UNT Libraries Government Documents Department

PHYTOPLANKTON AND BIOMASS DISTRIBUTION AT POTENTIAL OTEC SITES

Description: Net or large phytoplankton species composition and most phytoplankton abundance was measured at three OTEC sites. In the Gulf of Mexico and Hawaii, diatoms dominated while the blue-green algae Trichodesmium was most common at Puerto Rico. The species ratio of diatoms to dinoflagellates was approximately 1:1. The species diversity varied from site to site, Hawaii > Puerto Rico > Gulf of Mexico. Chlorophyll a, which is a measure of the pigment of all algae size ranges, showed a subsurface peak of 0.14-0.4 g per liter at 75 to 125 m. Occasional surface peaks up to 0.4 pg per liter occurred. Further refinement of collection techniques is needed to delineate the subtle environmental effects expected by OTEC plant discharges.
Date: June 1, 1979
Creator: Johnson, P.W. & Horne, A.J.
Partner: UNT Libraries Government Documents Department

Accelerated life test of the USDOE OC-OTEC experimental system refurbished with magnetic bearings for the 3rd stage vacuum compressor. Final report

Description: This report documents the accelerated life test (time-to-failure) performed, at the request of DOE, to evaluate the viability of the magnetic bearing system installed in the stage 3 vacuum pump. To this effect the plant was successfully operated for over 500 hours during the period September-November 1996. The first part of this report discusses system performance by deriving subsystem and system performance parameters from a typical record. This is followed by the discussion of the life tests. The instrumentation used to estimate the performance parameters given here is depicted. The third stage pump was operated for 535 hours without incident. It is concluded that magnetic bearings are the preferable choice for the OC-OTEC centrifugal vacuum pumps.
Date: April 1, 1997
Creator: Vega, L.A.
Partner: UNT Libraries Government Documents Department

OTEC Advanced Composite Cold Water Pipe: Final Technical Report

Description: Ocean Thermal Energy Conversion can exploit natural temperature gradients in the oceans to generate usable forms of energy (for example, cost-competitive baseload electricity in tropical regions such as Hawaii) free from fossil fuel consumption and global warming emissions.The No.1 acknowledged challenge of constructing an OTEC plant is the Cold Water Pipe (CWP), which draws cold water from 1000m depths up to the surface, to serve as the coolant for the OTEC Rankine cycle. For a commercial-scale plant, the CWP is on the order of 10m in diameter.This report describes work done by LMSSC developing the CWP for LM MS2 New Ventures emerging OTEC business. The work started in early 2008 deciding on the minimum-cost CWP architecture, materials, and fabrication process. In order to eliminate what in previous OTEC work had been a very large assembly/deployment risk, we took the innovative approach of building an integral CWP directly from theOTEC platform and down into the water. During the latter half of 2008, we proceeded to a successful small-scale Proof-of-Principles validation of the new fabrication process, at the Engineering Development Lab in Sunnyvale. During 2009-10, under the Cooperative Agreement with the US Dept. of Energy, we have now successfully validated key elements of the process and apparatus at a 4m diameter scale suitable for a future OTEC Pilot Plant. The validations include: (1) Assembly of sandwich core rings from pre-pultruded hollow 'planks,' holding final dimensions accurately; (2) Machine-based dispensing of overlapping strips of thick fiberglass fabric to form the lengthwise-continuous face sheets, holding accurate overlap dimensions; (3) Initial testing of the fabric architecture, showing that the overlap splices develop adequate mechanical strength (work done under a parallel US Naval Facilities Command program); and (4) Successful resin infusion/cure of 4m diameter workpieces, obtaining full wet-out and a non-discernable knitline between successive stepwise infusions.
Date: September 12, 2011
Creator: Miller, Dr. Alan & Ascari, Matthew
Partner: UNT Libraries Government Documents Department

Carbon dioxide release from ocean thermal energy conversion (OTEC) cycles

Description: This paper presents the results of recent measurements of CO{sub 2} release from an open-cycle ocean thermal energy conversion (OTEC) experiment. Based on these data, the rate of short-term CO{sub 2} release from future open-cycle OTEC plants is projected to be 15 to 25 times smaller than that from fossil-fueled electric power plants. OTEC system that incorporate subsurface mixed discharge are expected to result in no long-term release. OTEC plants can significantly reduce CO{sub 2} emissions when substituted for fossil-fueled power generation. 12 refs., 4 figs., 3 tabs.
Date: September 1, 1990
Creator: Green, H.J. (Solar Energy Research Inst., Golden, CO (USA)) & Guenther, P.R. (Scripps Institution of Oceanography, La Jolla, CA (USA))
Partner: UNT Libraries Government Documents Department

Ocean Thermal Energy Conversion (OTEC) Programmatic Environmental Analysis: Volume 2 -- Appendices

Description: The programmatic environmental analysis is an initial assessment of Ocean Thermal Energy Conversion (OTEC) technology considering development, demonstration and commercialization. It is concluded that the OTEC development program should continue because the development, demonstration, and commercialization on a single-plant deployment basis should not present significant environmental impacts. However, several areas within the OTEC program require further investigation in order to assess the potential for environmental impacts from OTEC operation, particularly in large-scale deployments and in defining alternatives to closed-cycle biofouling control: (1) Larger-scale deployments of OTEC clusters or parks require further investigations in order to assess optimal platform siting distances necessary to minimize adverse environmental impacts. (2) The deployment and operation of the preoperational platform (OTEC-1) and future demonstration platforms must be carefully monitored to refine environmental assessment predictions, and to provide design modifications which may mitigate or reduce environmental impacts for larger-scale operations. These platforms will provide a valuable opportunity to fully evaluate the intake and discharge configurations, biofouling control methods, and both short-term and long-term environmental effects associated with platform operations. (3) Successful development of OTEC technology to use the maximal resource capabilities and to minimize environmental effects will require a concerted environmental management program, encompassing many different disciplines and environmental specialties. This volume contains these appendices: Appendix A -- Deployment Scenario; Appendix B -- OTEC Regional Characterization; and Appendix C -- Impact and Related Calculations.
Date: January 1980
Creator: Sands, M. Dale
Partner: UNT Libraries Government Documents Department

The Marine Mammal Fauna of Potential Otec Sites in the Gulf of Mexico and Hawaii

Description: Twenty-seven marine mammal species have been recorded for the Gulf of Mexico, including 7 Mysticetes or baleen whales, 17 Odontocetes or toothed whales, 1 Sirenian (manatee), and 1 or 2 Pinnipeds or seals. The most common species in the Gulf is Tursiops truncatus, the bottlenosed dolphin, an inshore species. Offshore, Stenella plagiodon, the spotted dolphin, is fairly common. Most other species are recorded from very few sightings or strandings. None of the endangered species is common in potential OTEC sites in the Gulf of Mexico. Twenty-two marine mammals may occur in Hawaii; 2 Mystecetes, 19 Odonotocetes, and the endemic monk seal. The monk seal (Monachus schauinslandi), an endangered species, lives in the extreme northwestern island chain away from potential OTEC sites. Among the most common cetaceans in Hawaii is the endangered humpback whale (Megaptera novaeangliae). Stenella longirostris, the spinner dolphin; and Tursiops sp., the bottlenosed dolphin are also fairly common. The baleen whales feed on zooplankton during the summer in polar waters, and are migratory, while the toothed whales feed mainly on fish and squid, and are found in temperate or tropical regions year-round. The manatee is vegetarian and the pinnipeds are fish- or squid-eaters. Environmental effects of OTEC which may affect mammals are: toxic effects of biocide release or ammonia spill, biostimulating effects of seawater redistribution, oil spills, or effects of the physical presence of OTEC plants.
Date: May 1, 1979
Creator: Payne, S.F.
Partner: UNT Libraries Government Documents Department

OTEC support services quarterly technical progress report No. 14, 15 August 1981-14 November 1981

Description: The progress in the areas of system integration, system engineering, and management services is reported. The effort is divided into seven tasks: survey, analysis, and evaluation of technical program status; program technical monitoring; development and implementation of methodology for identification, evaluation, and trade-off for major subsystem configurations; technical assessments; OTEC system integration; environment and siting considerations; and transmission subsystem considerations. (LEW)
Date: November 1, 1981
Partner: UNT Libraries Government Documents Department

Ocean Thermal Energy Conversion (OTEC) program. FY 1977 program summary

Description: An overview is given of the ongoing research, development, and demonstration efforts. Each of the DOE's Ocean Thermal Energy Conversion projects funded during fiscal year 1977 (October 1, 1976 through September 30, 1977) is described and each project's status as of December 31, 1977 is reflected. These projects are grouped as follows: program support, definition planning, engineering development, engineering test and evaluation, and advanced research and technology. (MHR)
Date: January 1, 1978
Partner: UNT Libraries Government Documents Department

Modeling the Physical and Biochemical Influence of Ocean Thermal Energy Conversion Plant Discharges into their Adjacent Waters

Description: This paper describes the modeling work by Makai Ocean Engineering, Inc. to simulate the biochemical effects of of the nutrient-enhanced seawater plumes that are discharged by one or several 100 megawatt OTEC plants. The modeling is needed to properly design OTEC plants that can operate sustainably with acceptably low biological impact. In order to quantify the effect of discharge configuration and phytoplankton response, Makai Ocean Engineering implemented a biological and physical model for the waters surrounding O`ahu, Hawai`i, using the EPA-approved Environmental Fluid Dynamics Code (EFDC). Each EFDC grid cell was approximately 1 square kilometer by 20 meters deep, and used a time step of three hours. The biological model was set up to simulate the biochemical response for three classes of organisms: Picoplankton (< 2 um) such as prochlorococccus, nanoplankton (2-20 um), and microplankton (> 20 um) e.g., diatoms. The dynamic biological phytoplankton model was calibrated using chemical and biological data collected for the Hawaii Ocean Time Series (HOTS) project. Peer review of the biological modeling was performed. The physical oceanography model uses boundary conditions from a surrounding Hawai'i Regional Ocean Model, (ROM) operated by the University of Hawai`i and the National Atmospheric and Oceanic Administration. The ROM provided tides, basin scale circulation, mesoscale variability, and atmospheric forcing into the edges of the EFDC computational domain. This model is the most accurate and sophisticated Hawai'ian Regional Ocean Model presently available, assimilating real-time oceanographic observations, as well as model calibration based upon temperature, current and salinity data collected during 2010 near the simulated OTEC site. The ROM program manager peer-reviewed Makai's implementation of the ROM output into our EFDC model. The supporting oceanographic data was collected for a Naval Facilities Engineering Command / Makai project. Results: The model was run for a 100 MW OTEC Plant consisting of four separate ...
Date: September 29, 2012
Creator: PAT GRANDELLI, P.E.; ROCHELEAU, GREG; JOHN HAMRICK, Ph.D.; MATT CHURCH, Ph.D. & BRIAN POWELL, Ph.D.
Partner: UNT Libraries Government Documents Department

Ocean Thermal Energy Conversion: An overview

Description: Ocean thermal energy conversion, or OTEC is a technology that extracts power from the ocean's natural thermal gradient. This technology is being pursued by researchers from many nations; in the United States, OTEC research is funded by the US Department of Energy's Ocean Energy Technology program. The program's goal is to develop the technology so that industry can make a competent assessment of its potential -- either as an alternative or as a supplement to conventional energy sources. Federally funded research in components and systems will help OTEC to the threshold of commercialization. This publication provides an overview of the OTEC technology. 47 refs., 25 figs.
Date: November 1, 1989
Partner: UNT Libraries Government Documents Department

Results of scoping tests for open-cycle OTEC (ocean thermal energy conversion) components operating with seawater

Description: This report presents comprehensive documentation of the experimental research conducted on open-cycle ocean thermal energy conversion (OC-OTEC) components operating with seawater as a working fluid. The results of this research are presented in the context of previous analysis and fresh-water testing; they provide a basis for understanding and predicting with confidence the performance of all components of an OC-OTEC system except the turbine. Seawater tests have confirmed the results that were obtained in fresh-water tests and predicted by the analytical models of the components. A sound technical basis has been established for the design of larger systems in which net power will be produced for the first time from OC-OTEC technology. Design and operation of a complete OC-OTEC system that produces power will provide sufficient confidence to warrant complete transfer of OC-OTEC technology to the private sector. Each components performance is described in a separate chapter written by the principal investigator responsible for technical aspects of the specific tests. Chapters have been indexed separately for inclusion on the data base.
Date: September 1, 1990
Creator: Zangrando, F; Bharathan, D; Green, H J; Link, H F; Parsons, B K; Parsons, J M et al.
Partner: UNT Libraries Government Documents Department

Staging Rankine Cycles Using Ammonia for OTEC Power Production

Description: Recent focus on renewable power production has renewed interest in looking into ocean thermal energy conversion (OTEC) systems. Early studies in OTEC applicability indicate that the island of Hawaii offers a potential market for a nominal 40-MWe system. a 40-MWe system represents a large leap in the current state of OTEC technology. Lockheed Martin Inc. is currently pursuing a more realistic goal of developing a 10-MWe system under U.S. Navy funding (Lockheed 2009). It is essential that the potential risks associated with the first-of-its-kind plant should be minimized for the project's success. Every means for reducing costs must also be pursued without increasing risks. With this in mind, the potential for increasing return on the investment is assessed both in terms of effective use of the seawater resource and of reducing equipment costs.
Date: March 1, 2011
Creator: Bharathan, D.
Partner: UNT Libraries Government Documents Department

Hawaii energy strategy project 3: Renewable energy resource assessment and development program

Description: RLA Consulting (RLA) has been retained by the State of Hawaii Department of Business, Economic Development and Tourism (DBEDT) to conduct a Renewable Energy Resource Assessment and Development Program. This three-phase program is part of the Hawaii Energy Strategy (HES), which is a multi-faceted program intended to produce an integrated energy strategy for the State of Hawaii. The purpose of Phase 1 of the project, Development of a Renewable Energy Resource Assessment Plan, is to better define the most promising potential renewable energy projects and to establish the most suitable locations for project development in the state. In order to accomplish this goal, RLA has identified constraints and requirements for renewable energy projects from six different renewable energy resources: wind, solar, biomass, hydro, wave, and ocean thermal. These criteria were applied to areas with sufficient resource for commercial development and the results of Phase 1 are lists of projects with the most promising development potential for each of the technologies under consideration. Consideration of geothermal energy was added to this investigation under a separate contract with DBEDT. In addition to the project lists, a monitoring plan was developed with recommended locations and a data collection methodology for obtaining additional wind and solar data. This report summarizes the results of Phase 1. 11 figs., 22 tabs.
Date: November 1, 1995
Partner: UNT Libraries Government Documents Department

Alternate cycles applied to ocean thermal energy conversion

Description: Four open cycle OTEC concepts are described. These are: (1) single, vertical-axis turbine; (2) multiple, horizontal-axis turbines; (3) foam lift/hydraulic turbine; and (4) mist lift/hydraulic turbine. A preliminary assessment of achievable performance is made in addition to a description of the subsystem performance objectives which would support the achievement of the full potential inherent in these concepts. The results and conclusions of the paper include a description of the research objectives, achievement of which make open cycle OTEC a viable alternative as a nationl energy source.
Date: February 1, 1979
Creator: Shelpuk, B. & Lewandowski, A.
Partner: UNT Libraries Government Documents Department

OTEC support services. Quarterly technical progress report No. 3, 15 November 1978-14 February 1979

Description: System integration, system engineering, and management support services provided for the Ocean Thermal Energy Conversion Program of the Ocean Systems Branch, Division of Central Solar Technology are described. The six tasks include (1) survey, analysis, evaluation, and recommendation concerning program performance; (2) program technical monitoring; (3) development and implementation of methodology to identify and evaluate program alternatives; (4) technical assessments; (5) OTEC system integration; and (6) environment and siting considerations. (WHK)
Date: February 28, 1979
Creator: Walsh, J. P.
Partner: UNT Libraries Government Documents Department

OTEC thermal resource report for Mombasa

Description: The coastal waters off Mombassa, Kenya were selected for study for their potential for Ocean Thermal Energy Conversion (OTEC) use. The area examined is located in the southwestern equatorial region. The data file was searched between 40--45/sup 0/ East longitude and between 5/sup 0/ South latitude and 3/sup 0/ North latitude. The area south of the equator was examined separately from the area north of the equator. A usable thermal resource exists for both the northern and southern sections examined. The Mombassa site compares unfavorably with most of the other 10 sites studied under this contract if ..delta..T is used as the only criteria. An annual average ..delta..T of 20/sup 0/C is not reached until a depth of 1100 meters in the northern section, and at 1000 meters in the southern section. The average of the monthly mean ..delta..Ts at 500 meters is 17.0/sup 0/C in the north section and 17.6/sup 0/C in the southern section. The thermal resource is definitely better in the southern position. There is a mixed layer throughout the year that is advantageous for OTEC development. Winds and storms are not a problem for the site. Low sea and swell conditions are characteristic. Surface current conditions are fairly complicated. The distance from shore to the 1000 meter depth varies, depending on what latitude is chosen for the site. One thousand meter depths are between 30 and 130 kilometers (approx. = 18 and 70 nautical miles) from land.
Date: May 1, 1979
Creator: Wolff, W. A.
Partner: UNT Libraries Government Documents Department