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This report summarizes analytical evaluation of crack-opening areas and leak rates of superheated steam through flaws in steam generator tubes and erosion of neighboring tubes due to jet impingement of superheated steam with entrained particles from core debris created during severe accidents. An analytical model for calculating crack-opening area as a function of time and temperature was validated with tests on tubes with machined flaws. A three-dimensional computational fluid dynamics code was used to calculate the jet velocity impinging on neighboring tubes as a function of tube spacing and crack-opening area. Erosion tests were conducted in a high-temperature, high-velocity erosion rig at the University of Cincinnati, using micrometer-sized nickel particles mixed in with high-temperature gas from a burner. The erosion results, together with analytical models, were used to estimate the erosive effects of superheated steam with entrained aerosols from the core during severe accidents.

This conference paper describes the American Society for Testing and Materials (ASTM), the International Electrotechnical Commission (IEC), and the International Standards Organization (ISO) standard solar terrestrial spectra (ASTM G-159, IEC-904-3, ISO 9845-1) provide standard spectra for photovoltaic performance applications. Modern terrestrial spectral radiation models and knowledge of atmospheric physics are applied to develop suggested revisions to update the reference spectra. We use a moderately complex radiative transfer model (SMARTS2) to produce the revised spectra. SMARTS2 has been validated against the complex MODTRAN radiative transfer code and spectral measurements. The model is proposed as an adjunct standard to reproduce the reference spectra. The proposed spectra represent typical clear sky spectral conditions associated with sites representing reasonable photovoltaic energy production and weathering and durability climates. The proposed spectra are under consideration by ASTM.

This report summarizes the development of Regional Transmission Organizations (RTOs) and assesses the potential implications of market rules for renewable energy technologies. The report focuses on scheduling provisions, as these have proved problematic in some cases for intermittent renewable energy technologies. Market rules of four RTOs-the Pennsylvania-Maryland-New Jersey ISO, the ERCOT ISO, the Midwest ISO and the New York ISO (NYISO)-were examined to determine the impact on intermittent renewable energy projects such as wind energy generators. Also, a more general look was taken at how biomass power may fare in RTOs, specifically whether these technologies can participate in ancillary service markets. Lastly, an assessment was made regarding the implications for renewable energy technologies of a Northeast-wide RTO that would combine the three existing Northeast ISOs (the aforementioned PJM and NYISOs, as well as ISO New England).

Fact sheet describing the Oklahoma and Tulsa Clean Cities Coalitions and their commitment to the alternative fuel industry.

Over the past several years, there has been considerable development and application of wind forecasting models. The main purpose of these models is to provide grid operators with the best information available so that conventional power generators can be scheduled as efficiently and as cost-effectively as possible. One of the important ancillary services is reserves, which involves scheduling additional capacity to guard against shortfalls. In a recent paper, Strbac and Kirschen[1] proposed a method to allocate the reserve burden to generators. Although Milligan adapted this technique to wind plants[2], neither of these papers accounts for the wind forecast in the reliability calculation. That omission is rectified here. For the system studied in this paper, we found that a reserve allocation scheme using 1-hour forecasts results in a small allocation of system reserve relative to the rated capacity of the wind power plant. This reserve allocation is even smaller when geographically dispersed wind sites are used instead of a large single site.

Wind Power Today is an annual publication that provides an overview of the U.S. Department of Energy's Wind Energy Program accomplishments for the previous year. The purpose of Wind Power Today is to show how DOE's Wind Energy Program supports wind turbine research and deployment in hopes of furthering the advancement of wind technologies that produce clean, low-cost, reliable energy. Content objectives include: educate readers about the advantages and potential for widespread deployment of wind energy; explain the program's objectives and goals; describe the program's accomplishments in research and application; examine the barriers to widespread deployment; describe the benefits of continued research and development; facilitate technology transfer; and attract cooperative wind energy projects with industry. This 2001 edition of Wind Power Today also includes discussions about wind industry growth in 2001, how DOE is taking advantage of low wind speed regions through advancing technology, and distributed applications for small wind turbines.

This case study highlights International Truck and Engine Corporation's optimization project on the compressed air system that serves its foundry, Indianapolis Casting Corporation. Due to the project's implementation, the system's efficiency was greatly improved, allowing the foundry to operate with less compressor capacity, which resulted in reduced energy consumption, significant maintenance savings, and more reliable production.

This conference paper describes the in-depth understanding of the defect formation and resulting changes in material quality occurring during the Cu(In,Ga)Se2 growth process is vital to the successful and widespread use of this photovoltaic material. In an attempt to develop such an understanding, we investigated the growth of Cu(In,Ga)Se2 thin-films from (In,Ga)2Se3 precursors. This was achieved by using energy- and time-resolved photoluminescence spectroscopies to characterize a series of thin-films, each removed at a different point along the reaction pathway of the''three-stage'' growth process. The resulting thin-films are representative of the absorber layer as it proceeds from a Cu-rich to In(Ga)-rich state. The experimental results support a growth model incorporating defect changes in the dominant defect states and improvement in the recombination lifetime during this final stage of the growth process as the material transitions to a Cu-poor phase.

In order to make the Wind Powering America effort a success, homeowners and landowners interested in purchasing grid-connected small wind energy systems must be provided with assistance and education. The Clean Power Estimator (CPE) program is a valuable tool for these individuals. In support of this educational effort, the National Renewable Energy Laboratory's (NRELs) National Wind Technology Center (NWTC) is integrating the CPE program with site-specific wind resource data. This paper describes how the CPE program works, how end users can determine the cost-effectiveness of wind for a specific location, and how companies can use the program to identify high-value wind locations.

The purpose of this work is to establish the electrical similarity of the Mock Tank site to S-112 tank site to determine if the Mock Tank requires modifications for the tests this summer. We accomplish this objective by determining the effective electrical resistivity of S-112 and comparing it with that of the Mock Tank. We also compare the expected sensitivities under S-112 and Mock Tank assuming that long electrodes are used.

Transparent conducting oxides (TCOs) are a group of materials that are widely used in solar cells and other optoelectronic devices. Recently, Cu-containing p-type TCOs such as MII Cu2 O2 (MIII=Mg, Ca, Sr, Ba) and CuMIII O2 (MIII=Al, Ga, In) have been proposed. Using first-principles band structure methods, we have systematically studied the electronic and optical properties of these p-type transparent oxides. For MII Cu2 O2 , we predict that adding a small amount of Ca into Sr Cu2 O2 can increase the transparency and conductivity. For CuMIII O2 , we explained the doping and band gap anomalies in this system and proposed a new approach to search for bipolar dopable wide-gap materials.

This conference paper describes Microcrystalline silicon films were grown with different thicknesses and different hydrogen dilution ratios on glass and Si substrates. Some films were deposited with a seed layer, whereas others were deposited directly on the substrate. We used atomic force microscopy, scanning electron microscopy, and X-ray diffraction to study the morphology and crystalline structure of the samples. We did not find a significant influence of the different substrates on the morphology or crystalline structure. The presence of the seed layer enhanced the crystallization process, decreasing the amount of amorphous layer present in the films. The microstructure of most films was formed by grains, with a subgrain structure. Films grown with low values of dilution ratio had (220) texture and elongated grains, whereas films deposited with high values of dilution ratio were randomly oriented and had an irregular shape.

This conference paper describes the measurement of the photovoltaic (PV) performance with respect to reference conditions requires measuring the performance with respect to a reference spectrum. Procedures were developed in the mid 1980s to correct measurements for errors relating to the spectral irradiance of the light source being different from the standard and the responsivity of the irradiance detector being different from the device under test. In principle, these procedures are exact, but require the measurement of the spectral irradiance of the light source and responsivity of the test device. This is problematic for most facilities that measure module performance. It has been suggested that a polynomial fit of the short-circuit current (I sc ) measured under natural sunlight divided by the total broadband irradiance as a function of air mass provides an accurate spectral correction factor. The polynomial correction factor is normalized to unity at an absolute air mass of 1.5.The polynomial correction factor is compared with the spectral correction factor for a variety of devices at two locations.

I will review the basic physical principles underlying the formation energy of various intrinsic defects in common photovoltaic materials. I then use the above principles to explain why doping of semiconductors is, in general, limited and which design principles can be used to circumvent such limits. This work can help design strategies of doping absorber materials as well as explain how TCOs work. Recent results on the surprising stability of polar (112)+ surfaces of CIS will also be described in this context.

This conference paper describes the performance data for 14 photovoltaic modules deployed at fixed-latitude tilt in the field are presented and compared. Module performance is monitored continuously for optimum power characteristics. Flat-plate module technologies representative of crystalline, amorphous, and polycrystalline silicon, and cadmium telluride and copper indium diselenide, are scrutinized for energy production, effective efficiency and performance ratio-ratio of effective to reference efficiency. Most performance ratios exhibit seasonal fluctuations largely correlated to air or module temperatures, varying between 80% and 100%. These ratios tend toward larger values during winter and vise versa, except for amorphous silicon and cadmium telluride modules. In a-Si cases, the situation appears reversed: better performance ratios are exhibited during late summer. The effective efficiency and average daily and yearly energy production are analyzed and quantified.

Brochure to promote interest in Allied Partnerships with DOE's Office of Energy Efficiency and Renewable Energy among industrial manufacturers, suppliers, trade associations, and other organizations.

This conference paper describes Consensus standards for determining the efficiency of a concentrator cell or module that have not been developed. NREL, Sandia National Laboratory, the Fraunhofer Institute for Solar Energy in Germany, and the Progress in Photovoltaics Efficiency Table authors have informally agreed upon concentrator-cell reference conditions. These conditions are 25C cell temperature, 1-sun=1000 W/m2 total irradiance, and the ASTM E891-87 direct-normal reference spectrum. Deficiencies in the direct reference spectrum are discussed, and a more representative reference spectrum for evaluating concentrator cells is proposed. The spectrum was generated by the SMARTS model, and the atmospheric parameters are as close as possible to the existing direct spectrum, with the exception that the aerosol optical depth at 500 nm is reduced from 0.27 to 0.085.

This conference paper describes the III-V semiconductors grown on silicon substrates are very attractive for lower-cost, high-efficiency multijunction solar cells, but lattice-mismatched alloys that result in high dislocation densities have been unable to achieve satisfactory performance. GaNxP1-x-yAsy is a direct-gap III-V alloy that can be grown lattice-matched to Si when y= 4.7x - 0.1. We propose the use of lattice-matched GaNPAs on silicon for high-efficiency multijunction solar cells. We have grown GaNxP1-x-yAsy on GaP (with a similar lattice constant to silicon) by metal-organic chemical vapor phase epitaxy with direct band-gaps in the range of 1.5 to 2.0 eV. We demonstrate the performance of single-junction GaNxP1-x-yAsy solar cells grown on GaP substrates and discuss the prospects for the development of monolithic high-efficiency multijunction solar cells based on silicon substrates.

A new collegiate competition, called the Solar Decathlon, is under way. Fourteen teams from colleges and universities across the United States, including Puerto Rico, will assemble on the National Mall in Washington, DC, in late September 2002. They will compete to capture, convert, store, and use enough solar energy to power small, solar-powered, energy-efficient homes that they have designed, built, and transported to the site. Solar Decathletes will be required to provide all the energy for an entire household, including a home-based business and the transportation needs of the household and business. During the event, only the solar energy available within the perimeter of each house may be used to generate the power needed to compete in the ten Solar Decathlon contests. The event is sponsored by the U.S. Department of Energy, National Renewable Energy Laboratory, and private-sector partners BP Solar, American Institute of Architects, Electronic Data Systems, and Home Depot.

II-VI binary thin-film solar cells based on cadmium telluride (CdTe) and I-III-VI ternary thin-film solar cells based on copper indium diselenide (CIS) and related materials have been the subject of intense research and development in the past few years. Substantial progress has been made thus far in the area of materials research, device fabrication, and technology development, and numerous applications based on CdTe and CIS have been deployed worldwide. World record efficiency of 16.5% has been achieved by NREL scientists for a thin-film CdTe solar cell using a modified device structure. Also, NREL scientists achieved world-record efficiency of 21.1% for a thin-film CIGS solar cell under a 14X concentration and AM1.5 global spectrum. When measured under a AM1.5 direct spectrum, the efficiency increases to 21.5%. Pathways for achieving 25% efficiency for tandem polycrystalline thin-film solar cells are elucidated. R&D issues relating to CdTe and CIS are reported in this paper, such as contact stability and accelerated life testing in CdTe, and effects of moisture ingress in thin-film CIS devices. Substantial technology development is currently under way, with various groups reporting power module efficiencies in the range of 7.0% to 12.1% and power output of 40.0 to 92.5 W. A number …

The Department of Energy (DOE) Distributed Power Program (DPP) is conducting work to complete, validate in the field, and support the development of a national interconnection standard for distributed energy resources (DER), and to address the institutional and regulatory barriers slowing the commercial adoption of DER systems. This work includes support for the IEEE standards, including P1547 Standard for Interconnecting Distributed Resources with Electric Power Systems, P1589 Standard for Conformance Test Procedures for Equipment Interconnecting Distributed Resources with Electric Power Systems, and the P1608 Application Guide. Work is also in progress on system integration research and development (R&D) on the interface and control of DER with local energy systems. Additional efforts are supporting high-reliability power for industry, evaluating innovative concepts for DER applications, and exploring plug-and-play interface and control technologies for intelligent autonomous interconnection systems. This paper summarizes (1) the current status of the IEEE interconnection standards and application guides in support of DER, and (2) the R&D in progress at the National Renewable Energy Laboratory (NREL) for interconnection and system integration and application of distributed energy resources.

The Lake Roosevelt Fisheries Evaluation Program is the result of a merger between two projects, the Lake Roosevelt Monitoring Program (BPA No. 8806300) and the Lake Roosevelt Data Collection Project (BPA No. 9404300). These projects were merged in 1996 to continue work historically completed under the separate projects, and is now referred to as the Lake Roosevelt Fisheries Evaluation Program. Creel and angler surveys estimated that anglers made 196,775 trips to Lake Roosevelt during 1998, with an economic value of $8.0 million dollars, based on the Consumer Price Index (CPI). In 1998 it was estimated that 9,980 kokanee salmon, 226,809 rainbow trout, 119,346 walleye, and over 14,000 smallmouth bass and other species were harvested. Creel data indicates that hatchery reared rainbow trout contribute substantially to the Lake Roosevelt fishery. The contribution of kokanee salmon to the creel has not met the expectations of fishery managers to date, and is limited by entrainment from the reservoir, predation, and possible fish culture obstacles. The 1998 Lake Roosevelt Fisheries Creel and Population Analysis Annual Report includes analyses of the relative abundance of fish species, and reservoir habitat relationships (1990-1998). Fisheries surveys (1990-1998) indicate that walleye and burbot populations appear to be increasing, while …

This describes the advertising of cover page of 2001 NSLS Activity Report (National Synchrotron Light Source).