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Description: Biomass derived energy currently accounts for about 3 quads of total primary energy use in the United States. Of this amount, about 0.8 quads are used for power generation. Several biomass energy production technologies exist today which contribute to this energy mix. Biomass combustion technologies have been the dominant source of biomass energy production, both historically and during the past two decades of expansion of modern biomass energy in the U. S. and Europe. As a research and development activity, biomass gasification has usually been the major emphasis as a method of more efficiently utilizing the energy potential of biomass, particularly wood. Numerous biomass gasification technologies exist today in various stages of development. Some are simple systems, while others employ a high degree of integration for maximum energy utilization. The purpose of this study is to conduct a technical and economic comparison of up to three biomass gasification technologies, including the carbon dioxide emissions reduction potential of each. To accomplish this, a literature search was first conducted to determine which technologies were most promising based on a specific set of criteria. The technical and economic performances of the selected processes were evaluated using computer models and available literature. Using these results, the carbon sequestration potential of the three technologies was then evaluated. The results of these evaluations are given in this final report.
Date: June 1, 2002
Creator: Rollins, Martha L.; Reardon, Les; Nichols, David; Lee, Patrick; Moore, Millicent; Crim, Mike et al.
Partner: UNT Libraries Government Documents Department

An assessment of worldwide supercomputer usage

Description: This report provides a comparative study of advanced supercomputing usage in Japan and the United States as of Spring 1994. It is based on the findings of a group of US scientists whose careers have centered on programming, evaluating, and designing high-performance supercomputers for over ten years. The report is a follow-on to an assessment of supercomputing technology in Europe and Japan that was published in 1993. Whereas the previous study focused on supercomputer manufacturing capabilities, the primary focus of the current work was to compare where and how supercomputers are used. Research for this report was conducted through both literature studies and field research in Japan.
Date: January 1, 1995
Creator: Wasserman, H.J.; Simmons, M.L. & Hayes, A.H.
Partner: UNT Libraries Government Documents Department

Decreasing Cloudiness Over China: An Updated Analysis Examining Additional Variables

Description: As preparation of the IPCC's Third Assessment Report takes place, one of the many observed climate variables of key interest is cloud amount. For several nations of the world, there exist records of surface-observed cloud amount dating back to the middle of the 20th Century or earlier, offering valuable information on variations and trends. Studies using such databases include Sun and Groisman (1999) and Kaiser and Razuvaev (1995) for the former Soviet Union, Angel1 et al. (1984) for the United States, Henderson-Sellers (1986) for Europe, Jones and Henderson-Sellers (1992) for Australia, and Kaiser (1998) for China. The findings of Kaiser (1998) differ from the other studies in that much of China appears to have experienced decreased cloudiness over recent decades (1954-1994), whereas the other land regions for the most part show evidence of increasing cloud cover. This paper expands on Kaiser (1998) by analyzing trends in additional meteorological variables for Chi na [station pressure (p), water vapor pressure (e), and relative humidity (rh)] and extending the total cloud amount (N) analysis an additional two years (through 1996).
Date: January 14, 2000
Creator: Kaiser, D.P.
Partner: UNT Libraries Government Documents Department

A Review and Analysis of European Industrial Experience in Handling LWR Spent Fuel and Vitrified High-Level Waste

Description: The industrial facilities that have been built or are under construction in France, the United Kingdom, Sweden, and West Germany to handle light-water reactor (LWR) spent fuel and canisters of vitrified high-level waste before ultimate disposal are described and illustrated with drawings and photographs. Published information on the operating performance of these facilities is also given. This information was assembled for consideration in planning and design of similar equipment and facilities needed for the Federal Waste Management System in the United States.
Date: July 10, 2001
Creator: Blomeke, J.O.
Partner: UNT Libraries Government Documents Department

Prognostic Modeling of Long-Range Atmospheric Pollutant Transport for ETEX

Description: The ability to forecast the transport and diffusion of airborne contaminants over long distances is vital when responding to nuclear emergencies. Atmospheric models used in such emergency response applications must be able to include the effects of the evolving synoptic weather systems in a timely manner. The European Tracer EXperiment (ETEX), conducted in October and November 1994, is designed to evaluate the performance of such models. In addition to the tracer experiments, concurrent real-time modeling exercises were conducted by some 24 organizations world-wide, including the Savannah River Technology Center (SRTC) of the U.S. Department of Energy`s Savannah River Site. This paper describes the forecast results obtained by atmospheric modelers at SRTC in applying an advanced three-dimensional modeling system to forecast tracer transport and diffusion during ETEX. Forecast results from the first of two tracer experiments are presented in this preprint paper. Data for the tracer gas concentrations is not yet available; however, surface and sounding data are available from the time periods of the releases. This paper will focus on the evaluation of the forecasts in light of the surface wind data, and relate the forecast evaluations to the differences in the tracer gas dispersion predicted using these forecasts. Plume transport and diffusion results were reported previously.
Date: September 14, 1995
Creator: Griggs, D.P.
Partner: UNT Libraries Government Documents Department

Total environmental warming impact (TEWI) calculations for alternative automative air-conditioning systems

Description: The Montreal Protocol phase-out of chlorofluorocarbons (CFCs) has required manufacturers to develop refrigeration and air-conditioning systems that use refrigerants that can not damage stratospheric ozone. Most refrigeration industries have adapted their designs to use hydrochlorofluorocarbon (HCFC) or hydrofluorocarbon (HFC) refrigerants; new automobile air- conditioning systems use HFC-134a. These industries are now being affected by scientific investigations of greenhouse warming and questions about the effects of refrigerants on global warming. Automobile air-conditioning has three separate impacts on global warming; (1) the effects of refrigerant inadvertently released to the atmosphere from accidents, servicing, and leakage; (2) the efficiency of the cooling equipment (due to the emission of C0{sub 2} from burning fuel to power the system); and (3) the emission of C0{sub 2} from burning fuel to transport the system. The Total Equivalent Warming Impact (TEWI) is an index that should be used to compare the global warming effects of alternative air-conditioning systems because it includes these contributions from the refrigerant, cooling efficiency, and weight. This paper compares the TEWI of current air-conditioning systems using HFC-134a with that of transcritical vapor compression system using carbon dioxide and systems using flammable refrigerants with secondary heat transfer loops. Results are found to depend on both climate and projected efficiency of C0{sub 2}systems. Performance data on manufacturing prototype systems are needed to verify the potential reductions in TEWI. Extensive field testing is also required to determine the performance, reliability, and ``serviceability`` of each alternative to HFC-134a to establish whether the potential reduction of TEWI can be achieved in a viable consumer product.
Date: January 1, 1997
Creator: Sand, J.R. & Fischer, S.K.
Partner: UNT Libraries Government Documents Department

The Virtual Library in Action

Description: The SLAC Library has for many years provided SPIRES-HEP, a 300,000 record bibliographic database, to the world particle physics community via the Internet as well as through clone sites in Europe and Japan. The 1991 introduction of the e-print archives at LANL coupled with the World-Wide-Web (WWW) from CERN suddenly made it possible to provide easy linkage between bibliographic database records and the actual full-text of papers. The SLAC Library has turned this possibility into reality by converting hundreds of TeX source documents each month into viewable postscript complete with figures. These (now more than 20,000) postscript files are linked to the HEP database, and the full-text is rendered universally visible via WWW. We discuss the project, the collaboration of physicists and librarians, what is easy, what is hard, and our vision for the future.
Date: July 2, 1999
Creator: Addis, Louise
Partner: UNT Libraries Government Documents Department

International petroleum statistics report, June 1995

Description: The report presents data on international oil production, demand, imports, exports, and stocks. The report has four sections. Section 1 contains time series data on world oil production, and on oil demand and stocks in the Organization for Economic Cooperation and Development (OECD). This section contains annual data beginning in 1985, and monthly data for the most recent two years. Section 2 presents an oil supply/demand balance for the world. This balance is presented in quarterly intervals for the most recent two years. Section 3 presents data on oil imports by OECD countries. This section contains annual data for the most recent year, quarterly data for the most recent two quarters, and monthly data for the most recent twelve months. Section 4 presents annual time series data on world oil production and oil stocks, demand, and trade in OECD countries. World oil production and OECD demand data are for the years 1970 through 1994; OECD stocks from 1973 through 1994; and OECD trade from 1984 through 1994. 4 figs., 45 tabs.
Date: June 27, 1995
Partner: UNT Libraries Government Documents Department

Neutrino Factory Designs and R&D

Description: The development of a very intense muon source capable of producing a millimole of muons per year would enable a Neutrino Factory [1], and perhaps eventually a Muon Collider [2], to be built. In the last two years Neutrino Factory physics studies [3] have mapped out an exciting Neutrino Factory physics program. In addition, Neutrino Factory feasibility studies [4-6] have yielded designs that appear to be ''realistic'' provided the performance parameters for the critical components can be achieved. Some of the key components will need a vigorous R&D program to meet the requirements. Neutrino Factory R&D activities in Europe [7], Japan [6,8], and the US [9] have resulted in three promising variants of the basic Neutrino Factory design. In the following the various Neutrino Factory schemes are briefly described. The main R&D issues and the ongoing R&D programs are summarized.
Date: January 9, 2004
Creator: Geer, Steve
Partner: UNT Libraries Government Documents Department

Magnet R&D for future colliders

Description: High-energy colliders complementing and expanding the physics reach of LHC are presently under study in the United States, Europe and Japan. The magnet system is a major cost driver for hadron colliders at the energy frontier, and critical to the successful operation of muon colliders. Under most scenarios, magnet design as well as vacuum and cryogenic systems are complicated by high radiation loads. Magnet R&D programs are underway worldwide to take advantage of new developments in superconducting materials, achieve higher efficiency and simplify fabrication while preserving accelerator-class field quality. A review of recent progress in magnet technology for future colliders is presented, with emphasis on the most innovative design concepts and fabrication techniques.
Date: June 14, 2001
Creator: Sabbi, Gian Luca
Partner: UNT Libraries Government Documents Department

Black carbon emissions in the United Kingdom during the past four decades: An empirical analysis

Description: We use data from a unique 40-year record of 150 urban and rural stations in the ''Black Smoke and SO2 Network'' in Great Britain to infer information about sources of atmospheric black carbon (BC). The data show a rapid decline of ambient atmospheric BC between 1962 and the early 1990s that exceeds the decline in official estimates of BC emissions based only on amount of fuel use and mostly fixed emission factors. This provides empirical confirmation of the existence and large impact of a time-dependent ''technology factor'' that must multiply the rate of fossil fuel use. Current ambient BC amounts in Great Britain comparable to those in western and central Europe, with diesel engines being the principal present source. From comparison of BC and SO2 data we infer that current BC emission inventories understate true emissions in the U.K. by about a factor of two. The results imply that there is the potential for improved technology to achieve large reduction of global ambient BC. There is a need for comparable monitoring of BC in other countries.
Date: April 22, 2004
Creator: Novakov, T. & Hansen, J.E.
Partner: UNT Libraries Government Documents Department

A comparison of measured wind park load histories with the WISPER and WISPERX load spectra

Description: The blade-loading histories from two adjacent Micon 65/13 wind turbines are compared with the variable-amplitude test-loading histories known as the WISPER and WISPERX spectra. These standardized loading sequences were developed from blade flapwise load histories taken from nine different horizontal-axis wind turbines operating under a wide range of conditions in Europe. The subject turbines covered a broad spectrum of rotor diameters, materials, and operating environments. The final loading sequences were developed as a joint effort of thirteen different European organizations. The goal was to develop a meaningful loading standard for horizontal-axis wind turbine blades that represents common interaction effects seen in service. In 1990, NREL made extensive load measurements on two adjacent Micon 65/13 wind turbines in simultaneous operation in the very turbulent environment of a large wind park. Further, before and during the collection of the loads data, comprehensive measurements of the statistics of the turbulent environment were obtained at both the turbines under test and at two other locations within the park. The trend to larger but lighter wind turbine structures has made an understanding of the expected lifetime loading history of paramount importance. Experience in the US has shown that the turbulence-induced loads associated with multi-row wind parks in general are much more severe than for turbines operating individually or within widely spaced environments. Multi-row wind parks are much more common in the US than in Europe. In this paper we report on our results in applying the methodology utilized to develop the WISPER and WISPERX standardized loading sequences using the available data from the Micon turbines. While the intended purpose of the WISPER sequences were not to represent a specific operating environment, we believe the exercise is useful, especially when a turbine design is likely to be installed in a multi-row wind park.
Date: January 1, 1995
Creator: Kelley, N.D.
Partner: UNT Libraries Government Documents Department

Perspectives on an NWCC/NREL Assessment of Distributed Wind

Description: During 1998 and 1999, the National Wind Coordinating Committee (NWCC) conducted an assessment of distributed wind power. The project team was led by Princeton Economic Research, Inc., now known as Princeton Energy Resources International (PERI). Financial support was provided by the US Department of Energy (DOE) through the wind energy program at the National Renewable Energy Laboratory (NREL) and the Electric Power Research Institute (EPRI). Project oversight and review were provided by NWCC's Distributed Working Group. The overall objective for the NWCC assessment was to enhance understanding of business, policy, and technical issues associated with the deployment of wind-electric generating systems in the distributed-generation mode. In general, that mode is defined by placement of the generation close to customers-in contrast to large, distant central stations-and by electrical interconnection to the local distribution system-in contrast to higher voltage electrical transmission systems. As a follow-up to the assessment, NWCC intends to prepare a consensus-based issue brief that summarizes its findings and highlights the major results and conclusions for each stakeholder sector. This brief will also identify key action steps that could be undertaken by each stakeholder sector to facilitate the growth of distributed wind. The aim of this paper is to provide input to the NWCC for its consideration in developing the issue brief. Accordingly, this paper is in no way an NWCC consensus document. However, the authors hope to assist in the issue-brief preparation process by providing a starting point for NWCC's consideration. One of the authors, Joseph Cohen, led the team that performed the NWCC assessment. The other two were involved in management of the assessment effort on behalf of the contracting organizations and are active members of the NWCC. They feel the perspectives offered in this paper are well-grounded in the findings of the assessment research and can help ...
Date: September 13, 2000
Creator: Parsons, B.; Cohen, J. & DeMeo, E.
Partner: UNT Libraries Government Documents Department

Two decades of Mexican particle physics at Fermilab

Description: This report is a view from Fermilab of Mexican particle physics at the Laboratory since about 1980; it is not intended to be a history of Mexican particle physics: that topic is outside the expertise of the writer. The period 1980 to the present coincides with the growth of Mexican experimental particle physics from essentially no activity to its current state where Mexican groups take part in experiments at several of the world's major laboratories. Soon after becoming Fermilab director in 1979, Leon Lederman initiated a program to encourage experimental physics, especially experimental particle physics, in Latin America. At the time, Mexico had significant theoretical particle physics activity, but none in experiment. Following a visit by Lederman to UNAM in 1981, a conference ''Panamerican Symposium on Particle Physics and Technology'' was held in January 1982 at Cocoyoc, Mexico, with about 50 attendees from Europe, North America, and Latin America; these included Lederman, M. Moshinsky, J. Flores, S. Glashow, J. Bjorken, and G. Charpak. Among the conference outcomes were four subsequent similar symposia over the next decade, and a formal Fermilab program to aid Latin American physics (particularly particle physics); it also influenced a decision by Mexican physicist Clicerio Avilez to switch from theoretical to experimental particle physics. The first physics collaboration between Fermilab and Mexico was in particle theory. Post-docs Rodrigo Huerta and Jose Luis Lucio spent 1-2 years at Fermilab starting in 1981, and other theorists (including Augusto Garcia, Arnulfo Zepeda, Matias Moreno and Miguel Angel Perez) also spent time at the Laboratory in the 1980s.
Date: December 3, 2002
Creator: Rubinstein, Roy
Partner: UNT Libraries Government Documents Department

Geological challenges in radioactive waste isolation: Third worldwide review

Description: The broad range of activities on radioactive waste isolation that are summarized in Table 1.1 provides a comprehensive picture of the operations that must be carried out in working with this problem. A comparison of these activities with those published in the two previous reviews shows the important progress that is being made in developing and applying the various technologies that have evolved over the past 20 years. There are two basic challenges in perfecting a system of radioactive waste isolation: choosing an appropriate geologic barrier and designing an effective engineered barrier. One of the most important developments that is evident in a large number of the reports in this review is the recognition that a URL provides an excellent facility for investigating and characterizing a rock mass. Moreover, a URL, once developed, provides a convenient facility for two or more countries to conduct joint investigations. This review describes a number of cooperative projects that have been organized in Europe to take advantage of this kind of a facility in conducting research underground. Another critical development is the design of the waste canister (and its accessory equipment) for the engineered barrier. This design problem has been given considerable attention in a number of countries for several years, and some impressive results are described and illustrated in this review. The role of the public as a stakeholder in radioactive waste isolation has not always been fully appreciated. Solutions to the technical problems in characterizing a specific site have generally been obtained without difficulty, but procedures in the past in some countries did not always keep the public and local officials informed of the results. It will be noted in the following chapters that this procedure has caused some problems, especially when approval for a major component in a project was needed. ...
Date: December 1, 2001
Creator: Witherspoon Editor, P.A. & Bodvarsson Editor, G.S.
Partner: UNT Libraries Government Documents Department

INDEEP Annual report (1995-1996)

Description: The International database on Energy Efficiency Programs (INDEEP) project is designed to make available information on electric and gas utility demand-side management (DSM) programs, as well as DSM programs carried out by government agencies and others. Efforts in the program for this time period are described.
Date: June 1996
Creator: Vine, E.
Partner: UNT Libraries Government Documents Department

Plus c`est la meme chose: The future of nuclear weapons in Europe

Description: Since the end of the Cold War, the United States perhaps more than any other nuclear weapon state has deeply questioned the future role of nuclear weapons, both in a strategic sense and in Europe. It is probably the United States that has raised the most questions about the continuing need for and efficacy of nuclear weapons, and has expressed the greatest concerns about the negative consequences of continuing nuclear weapons deployment. In the US, this period of questioning has now come to a pause, if not a conclusion. In late 1994 the United States decided to continue to pursue reductions in numbers of nuclear weapons as well as other changes designed to reduce the dangers associated with the possession of nuclear weapons. But at the same time the US concluded that some number of nuclear forces would continue to be needed for national security for the foreseeable future. These necessary nuclear forces include a continuing but greatly reduced stockpile of nuclear bombs deployed in Europe under NATO`s New Strategic Concept. If further changes to the US position on nuclear weapons in Europe are to occur, it is likely to be after many years, and only in the context of dramatic additional improvements in the political and geo-political climate in and around Europe. The future role of nuclear weapons in Europe, as discussed in this report, depends in part on past and future decisions by the United States. but it must also be noted that other states that deploy nuclear weapons in Europe--Britain, France, and Russia, as well as the NATO alliance--have shown little inclination to discontinue their deployment of such weapons, whatever the United States might choose to do in the future.
Date: July 1, 1996
Creator: Maaranen, S.A.
Partner: UNT Libraries Government Documents Department

Interfacing microbiology and biotechnology. Conference abstracts

Description: The Interfacing Microbiology and Biotechnology Conference was attended by over 100 faculty, post-docs, students, and research scientists from the US, Europe, and Latin America. The conference successfully stimulated communication and the dissemination of knowledge among scientists involved in basic and applied research. The focus of the conference was on microbial physiology and genetics and included sessions on C1 metabolism, archaeal metabolism, proteases and chaperones, gene arrays, and metabolic engineering. The meeting provided the setting for in-depth discussions between scientists who are internationally recognized for their research in these fields. The following objectives were met: (1) The promotion of interaction and future collaborative projects among scientists involved in basic and applied research which incorporates microbial physiology, genetics, and biochemistry; (2) the facilitation of communication of new research findings through seminars, posters, and abstracts; (3 ) the stimulation of enthusiasm and education among participants including graduate and undergraduate students.
Date: May 19, 2001
Creator: Maupin, Julia A.
Partner: UNT Libraries Government Documents Department

Fuel cells at the crossroads : attitudes regarding the investment climate for the US fuel cell industry and a projection of industry job creation potential.

Description: Fuel Cells at the Crossroads examines financial community and fuel cell industry views on the investment climate for the fuel cell industry. It also explores the investment history of the US fuel cell industry and projects potential future job creation. The scope of the study included the transportation, stationary power generation and portable sectors. Interviews were conducted with industry and financial experts. The results of the interviews provide a snapshot of industry perspective just prior to President Bush's endorsement of a hydrogen economy in his 2003 State of the Union address. In April 2003, we conducted a spot check to test whether the State of the Union address had changed opinions. We found little change among the financial and investment communities, but some guarded new optimism among industry leaders. The general outlook of our sample was cautiously hopeful. There is no question, however, that the current climate is one of great uncertainty, particularly when compared with the enthusiasm that existed just a few years ago. Among other things: (1) Respondents generally believed that the energy industry will undergo profound change over the next few decades, resulting in some form of hydrogen economy. They acknowledged, however, that huge technology and cost hurdles must be overcome to achieve a hydrogen economy. (2) Respondents were worried about the future of the industry, including timeframes for market development, foreign competition, technical problems, and the current poor investment environment. (3) Respondents generally believed that the US federal government must provide strong leadership to ensure American leadership in the fuel cell industry. They believe that governments in Europe and Japan are highly committed to fuel cells, thus providing European and Japanese companies with significant advantages. (4) Respondents frequently mentioned several areas of concern, including the situation in Iraq, the increased commitment to fuel cells in Europe, ...
Date: May 27, 2004
Partner: UNT Libraries Government Documents Department

Short-Rotation Crops for Bioenergy: Proceedings of IEA, Bioenergy, Task 17 Meeting in Auburn, Alabama, USA, September 6-9, 1999

Description: These proceedings are the results of the third meeting of Task 17 (Short-Rotation Crops for Bioenergy) within the framework of International Energy Agency (IEA), Bioenergy. (Minutes from the meeting can be seen at page 91.) The meeting was held in Auburn, Alabama, USA, September 6--9, 1999. The meeting was held soon after President Clinton of the United States signed Executive Order No.13134: DEVELOPING AND PROMOTING BIOBASED PRODUCTS AND BIOENERGY on August 12, 1999. Executive orders in the US are official documents, through which the President of the US manages the operation of the Federal Government. This order outlines the administration's goal of tripling the use of biomass products and bioenergy in the US by the year 2010. During the time of this meeting, it was also known from sources in Europe that the European Union (EU) commission was working on draft instructions to its member countries on how to increase the use of renewable energy from six to twelve percent in Europe within 10 years. The objectives of Task 17 support the goals of member countries for bioenergy production and use. These objectives are as follows: to stimulate the full-scale implementation of energy crops in the participating countries; to strengthen the contacts and co-operation between participating countries, scientists, biomass producers, machine developers, entrepreneurs, and end users to select the most urgent research and development areas and suggest projects of co-operation; to inform Ex-Co- members; and to deliver proceedings from the meetings.
Date: January 30, 2001
Creator: Wright, L.L.
Partner: UNT Libraries Government Documents Department

International Energy Agency building energy simulation test (BESTEST) and diagnostic method

Description: This is a report on the Building Energy Simulation Test (BESTEST) project conducted by the Model Evaluation and Improvement International Energy Agency (IEA) Experts Group. The group was composed of experts from the Solar Heating and Cooling (SHC) Programme, Task 12 Subtask B, and the Energy Conservation in Buildings and Community Systems (BCS) Programme, Annex 21 Subtask C. Recognizing that the needs for model evaluation were similar in both IEA programmes, the combined Experts Group was approved by the Executive Committees in 1990. This is the first joint group organized by the respective IEA Executive Committees, and it has resulted in significant cost savings for all participating countries. The objective of this subtask has been to develop practical implementation procedures and data for an overall IEA validation methodology which has been under development by NREL since 1981, with refinements contributed by the United Kingdom. The methodology consists of a combination of empirical validation, analytical verification, and comparative analysis techniques. This report documents a comparative testing and diagnostic procedure for thermal models related to the architectural fabric of the building. Other projects (reported elsewhere) conducted by this group include work on empirical validation, analytical verification, and comparative test cases for commercial buildings. In the BESTEST project, a method was developed for systematically testing whole-building energy simulation programs and diagnosing the sources of predictive disagreement. Field trials of the method were conducted with a number of {open_quotes}reference{close_quotes} programs selected by the participants to represent the best state-of-the-art detailed simulation capability available in the United States and Europe. These included BLAST, DOE2, ESP, SERIRES, S3PAS, TASE, and TRNSYS.
Date: February 1, 1995
Creator: Judkoff, R. & Neymark, J.
Partner: UNT Libraries Government Documents Department

Fatigue damage estimate comparisons for northern European and U.S. wind farm loading environments

Description: Typical loading histories associated with wind turbine service environments in northern Europe and within a large wind farm in the continental US were recently compared by Kelley (1995) using the WISPER [Ten Have, 1992] loading standard and its development protocol. In this study, an equivalent load spectrum for a US wind farm was developed by applying the WISPER development protocol to representative service load histories collected from two adjacent turbines operating within a large wind farm in San Gorgonio Pass, California. The results of this study showed that turbines operating in the California wind farm experience many more loading cycles with larger peak-to-peak values for the same mean wind speed classification than their European counterparts. In this paper, the impact of the two WISPER-protocol fatigue-load spectra on service lifetime predictions are used to compare and contrast the impact of the two loading environments with one another. The service lifetime predictions are made using the LIFE2 Fatigue Analysis Code [Sutherland and Schluter, 1989] with the fatigue properties of typical fiber glass composite blade materials. Additional analyses, based on rainflow counted time histories from the San Gorgonio turbines, are also used in the comparisons. In general, these results indicate that the WISPER load spectrum from northern European sites significantly underestimates the WISPER protocol load spectrum from a US wind farm site; i.e., the WISPER load spectrum significantly underestimates the number and magnitude of the loads observed at a US wind farm site. The authors conclude that there are fundamental differences in the two service environments.
Date: May 1, 1995
Creator: Sutherland, H.J. & Kelley, N.D.
Partner: UNT Libraries Government Documents Department