SCIENTIFIC AND TECHNICAL AEROSPACE REPORTS
A Biweekly Publication of the National Aeronautics and Space Administration
VOLUME 44, ISSUE 4 - February 24, 2006
44 ENERGY PRODUCTION AND CONVERSION
Includes specific energy conversion systems, e.g., fuel cells; and solar, geothermal, windpower, and waterwave conversion systems; energy storage; and traditional power generators.
For technologies related to nuclear energy production see 73 Nuclear Physics.
For related information see also 07 Aircraft Propulsion and Power; 20 Spacecraft Propulsion and Power; and 28 Propellants and Fuels.
20060005728 National Renewable Energy Lab., Golden, CO USA
EFG Technology and Diagnostic R&D for Large-Scale PV Manufacturing. Final Subcontract, March 1, 2002-March 31, 2005
Kalejs, J.; Aurora, P.; Bathey, B.; Cao, J.; Doedderlein, J.; Oct. 2005; 36 pp.; In English Report No.(s): DE2005-15020504; NREL/SR-520-38680; No Copyright; Avail.: National Technical Information Service (NTIS)
The objective of this subcontract was to carry out R&D to advance the technology, processes, and performance of RWE Schott-Solar's wafer, cell, and module manufacturing lines, and help configure these lines for scaling up of edge-defined, film-fed growth (EFG) ribbon technology to the 50-100MWPV factory level. EFG ribbon manufacturing continued to expand during this subcontract period and now has reached a capacity of 40 MW. EFG wafer products were diversified over this time period. In addition to 10 cm x 10 cm and 10 cm x 15 cm wafer areas, which were the standard products at the beginning of this program, R&D has focused on new EFG technology to extend production to 12.5 cm x 12.5 cm EFG wafers. Cell and module production also has continued to expand in Billerica.Anew 12-MW cell line was installed and brought on line in 2003. R&D on this subcontract improved cell yield and throughput, and optimized the cell performance, with special emphasis on work to speed up wafer transfer, hence enhancing throughput. Improvements of wafer transfer processes during this program have raised cell line capacity from 12 MW to over 18 MW. Optimization of module manufacturing processes was carried out on new equipment installed during a manufacturing upgrade in Billerica to a 12-MW capacity to improve yield and reliability of products. NTIS
Manufacturing; Photovoltaic Conversion
20060005736 National Renewable Energy Lab., Golden, CO USA, Evergreen Solar, Inc., Marlboro, MA, USA
| |
| Tools for Aviation/Aerospace |
| IHS sells products and services designed to meet the needs of today's engineers. To learn more, and for a free quote, please complete the form below. |
|
Innovative Approaches to Low-Cost Module Manufacturing of String Ribbon Si PV Modules
Hanoka, J. I.; Brown, K.; Oct. 2005; 56 pp.; In English Report No.(s): DE2005-15020503; NREL/SR-520-38679; No Copyright; Avail.: National Technical Information Service (NTIS)
A three year PV Manufacturing Research and Development subcontract has resulted in major gains for Evergreen Solar. As a result of this work, Evergreen is now poised to take String Ribbon technology to new heights. In the ribbon growth area, project Gemini - the growth of dual ribbons from a single crucible-has reached or exceeded all the manufacturing goals set for it.
This project grew from an R&D concept to a production pilot phase and finally to a full production phase, all within the span of this subcontract. A major aspect of the overall effort was the introduction of controls and instrumentation as in-line diagnostic tools. In the ribbon production area, the result has been a 12% increase in yields, a 10% increase in machine uptime, and the flattest ribbon ever grown at Evergreen. In the cell area, advances in process development and robotic handling of Gemini wafers have contributed, along with the advances in crystal growth, to a yield improvement of 6%. Particularly noteworthy in the cell area was the refinement of the no-etch process whereby the as-grown ribbon surface could be controlled sufficiently to allow this process to succeed as well as it has. This process obviates any need for wet chemistry or etching between ribbon growth and diffusion.
Evergreen's factory in Marlboro, MA, has expanded to a maximal capacity of about 15 MW/yr. The net result of all of this has been a reduction of 33% in direct manufacturing costs, a very notable achievement. Earlier in the project, the focus was on monolithic module development.With the Gemini advances described above, the focus of the entire project changed and the monolithic module work was brought to a close during this second year of the overall three year project.
A significant advance in this technology was the development of a conductive adhesive in combination with Evergreen's proprietary backskin and encapsulant. 25 W size experimental monolithic modules have been tested and found to able to withstand up to 1600 thermal cycles. NTIS
Low Cost; Manufacturing; Modules; Photovoltaic Cells; Ribbons; Solar Cells; Strings
20060005737 National Renewable Energy Lab., Golden, CO USA, Astrosystems International, Inc., Newark, DE, USA
High Volume Manufacturing of Silicon-Film Solar Cells and Modules. Final Subcontract Report, February 26, 2003-September 30, 2003
Rand, J. A.; Culik, J. S.; Oct. 2005; 48 pp.; In English Report No.(s): DE2005-15020502; NREL/SR-520-38677; No Copyright; Avail.: National Technical Information Service (NTIS)
The objective of the PV Manufacturing R&D subcontract was to continue to improve AstroPower's technology for manufacturing Silicon-Film wafers, solar cells, and modules to reduce costs, and increase production yield, throughput, and capacity. As part of the effort, new technology such as the continuous back metallization screen-printing system and the laser scribing system were developed and implemented. Existing processes, such as the silicon nitride antireflection coating system and the fire-through process were optimized. Improvements were made to the statistical process control (SPC) systems of the major manufacturing processes: feedstock preparation, wafer growth, surface etch, diffusion, and the anti-reflection coating process.
These process improvements and improved process control have led to an increase of 5% relative power, and nearly 15% relative improvement in mechanical and visual yield. Significant progress was made in reducing the amount of silicon consumed by the Silicon-Film process. The introduction of a near net shape wafer formation process has reduced the amount of silicon feedstock used per wafer by 40% and other developments in the feedstock preparation and wafer growth processes promise to further reduce the amount of silicon used per wafer by an additional 15%.
The Silicon-Film process has consistently demonstrated a high tolerance to impurities.Work has been done to understand the impact of impurities on device and growth performance. Experimentation has focused on tuning the growth parameters and optimizing getter sequences to reduce the detrimental effects of these impurities. To take advantage of Silicon-Film's high tolerance to impurities, efforts were made to upgrade metallurgical-grade (MG) silicon to a purity level needed for the Silicon-Film process through the continuous uni-directional solidification (CUDS) process.
Under the PV Manufacturing R&D subcontract a new large area module lamination manufacturing line with a new large area module tester was designed to accommodate the APx-140 modules. In order to reduce module defects, a more rigorous pre-lamination inspection system equipped with an IR inspection station was implemented and improvements in the module design have focused on reducing series resistance losses by increasing the crossectional area of the tabbing. On the system level AstroPower has developed a new method to mount large area APx-140 modules, which promises to be lower cost and more aesthetically appealing than the typical rack mount system. NTIS
Manufacturing; Modules; Silicon Films; Solar Cells
20060005738 Department of Energy, Washington, DC, USA
| |
| Aerospace Engineering Design |
| ESDU packages provide validated design data, methods and software, offering a valuable toolset to aerospace engineers. To learn more, and for a free quote, please complete the form below. |
|
DOE Solar Energy Technologies Program, FY 2004 Annual Report
Sep. 2005; 200 pp.; In English Report No.(s): DE2005-15020473; No Copyright; Avail.: Department of Energy Information Bridge
The Solar Energy Technologies Program, located within the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy, is responsible for developing solar energy technologies that can convert sunlight to useful energy and make that energy available to satisfy a significant portion of our nation's energy needs in a cost-effective way. The Solar Program supports research and development that addresses a wide range of applications, including on-site electricity generation, thermal energy for space heating and hot water, and large-scale power production. This is a great time to be involved with solar energy. Photovoltaic (PV) systems are being installed in the USA and around the world in unprecedented quantities. The concentrating solar power industry has broken ground on its first major plant in more than 10 years, and, with strong support from the Western Governor's Association, more plants are planned over the next few years. One of the largest segments of the solar industry is solar pool heating, and we are working with U.S. industry to leverage this expertise into new solar water heating products. NTIS
Energy Technology; Solar Energy
20060005750 National Renewable Energy Lab., Golden, CO USA, ITN Energy Systems, Inc., Littleton, CO, USA
Trajectory-Oriented and Fault-Tolerant-Based Intelligent Process Control for Flexible CIGS PV Module Manufacturing. Final Technical Report, May 13, 2002-May 30, 2005
Simpson, L.; Britt, J.; Birkmire, R.; Vincent, T.; Oct. 2005; 70 pp.; In English Report No.(s): DE2005-15020505; NREL/SR-520-38681; No Copyright; Avail.: National Technical Information Service (NTIS)
ITN Energy Systems, Inc., and Global Solar Energy, Inc., with the assistance of NRELs PV Manufacturing R&D program have continued the advancement of CIGS production technology through the development of trajectory oriented predictive/ control models, fault tolerance control, control platform development, in-situ sensors, and process improvements. Modeling activities included the development of physics-based and empirical models for CIGS and sputter deposition processing, implementation of model-based control, and application of predictive models to the construction of new evaporation sources and for control.
Model-based control is enabled through implementation of reduced or empirical models into a control platform. Reliability improvement activities include implementation of preventive maintenance schedules; detection of failed sensors/equipment and reconfiguration to continue processing; and systematic development of fault prevention and reconfiguration strategies for the full range of CIGS PV production deposition processes.
In-situ sensor development activities have resulted in improved control and indicated the potential for enhanced process status monitoring and control of the deposition processes. Substantial process improvements have been made, including significant improvement in CIGS uniformity, thickness control, efficiency, yield, and throughput. In large measure, these gains have been driven by process optimization, which in turn have been enabled by control and reliability improvements due to this PV Manufacturing R&D program. This has resulted in substantial improvements of flexible CIGS PV module performance and efficiency. This program has also resulted in implementation of fully functional process control software with accompanying graphical user interfaces to enable implementation of model-based control and reconfiguration capabilities and in-situ sensor based real-time control. Finally, the program has been leveraged to develop improved processing systems both at the component and configuration levels. NTIS
Copper; Fault Tolerance; Gallium; Indium; Manufacturing; Photovoltaic Conversion; Selenides; Trajectories
20060006374 National Renewable Energy Lab., Golden, CO USA
PowerLight Corporation Lean Manufacturing, PV Manufacturing R&D Phase 1 Report 6 December 2001-31 March 2003
Hargis, L.; Botkin, J.; Jun. 2005; 38 pp.; In English Report No.(s): DE2005-15016394; NREL/SR-520-35581; No Copyright; Avail.: National Technical Information Service (NTIS)
PowerLight Corporation (PowerLight) has completed Phase I of its PV Manufacturing R&D subcontract, PowerGuard(Trade Name) Lean Manufacturing, Subcontract No. NDO-1-30628-04. The overall technical goal of this project was to reduce the cost of PowerGuard manufacturing while simultaneously improving product quality. This will enable PowerLight to scale up production capacity as the market for PowerGuard continues to grow. Through the introduction of world-class lean manufacturing techniques, PowerLight was to cut out waste in the manufacturing process of PowerGuard. The manufacturing process was to be overhauled with an objective of removing as much as possible those steps that do not add value to the product. Quality of finished goods was also to be improved through the use of statistical process control and error-proofing in the manufacturing process. Factory operations were also to be addressed in order to streamline those factory activities that support the manufacturing process. NTIS
Manufacturing; Power Supplies; Photovoltaic Conversion; Research and Development
20060006414 National Renewable Energy Lab., Golden, CO USA
Plasma-Assisted Co-evaporation of S and Se for Wide Band Gap Chalcopyrite Photovoltaics: Final Subcontract Report, December 2001 -- April 2005
Repins, I.; Woldem, C.; Aug. 2005; 62 pp.; In English Report No.(s): DE2005-15016822; NREL/SR-520-38357; No Copyright; Avail.: National Technical Information Service (NTIS)
In this work, ITN Energy Systems (ITN) and lower-tier subcontractor Colorado School of Mines (CSM) explore the replacement of the molecular chalcogen precursors during deposition (e.g., Se2 or H2Se) with more reactive chalcogen monomers or radicals (e.g., Se). Molecular species are converted to atomic species in a low-pressure inductively coupled plasma (ICP). This program explored the use of plasma-activated chalcogen sources in CIGS co-evaporation to lower CIGS deposition temperature, increase utilization, increase deposition rate, and improve S:Se stoichiometry control. Plasma activation sources were designed and built, then operated and characterized over a wide range of conditions. Optical emission and mass spectrometry data show that chalcogens are effectively dissociated in the plasma. The enhanced reactivity achieved by the plasma processing was demonstrated by conversion of pre-deposited metal films to respective chalcogen-containing phases at low temperature and low chalcogen flux. The plasma-assisted co-evaporation (PACE) sources were also implemented in CIGS co-evaporation. No benefit from PACE was observed in device results, and frequent deposition failures occurred. NTIS
Broadband; Energy Gaps (Solid State); Evaporation; Photovoltaic Conversion; Plasmas (Physics); Solar Energy
Source: NASA
|
IHS sells products and services designed to meet the needs of today's aviation & aerospace engineers, including:
- Quick access to FAA, JAA, ICAO and UK-CAA information and regulations.
- Validated engineering methods, data, principles, worked examples, programs and related equations on over 1340 specific aerospace, process, structural and mechanical engineering topics.
- The IHS Fasteners eCatalog, providing decision support for the identification, specification and sourcing of aerospace & defense standard fasteners/hardware such as bolts, screws, nuts, washers, rivets, studs, etc.
- Standards documents and collections from the top aerospace & aviation standards development organizations, including SAE International, AIAA, AIA, FAA and NASA.
|