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Proceedings of the International Energy Agency Conference on Pyranometer Measurements: Final Report; 16 - 20 March 1981, Boulder, Colorado

Description: A conference of pyranometry measurement experts from seven nations was held 16-20 March 1981 in Boulder, Colorado, USA, under the auspices of the International Energy Agency, the United States Department of Energy, and the Solar Energy Research Institute. This report documents the technical presentations, background, and the results and recommendations of the conference.
Date: October 1, 1982
Creator: Riches, M. R.; Stoffel, T. L. & Wells, C. V.
Partner: UNT Libraries Government Documents Department

Entrained-Flow, Fast Ablative Pyrolysis of Biomass - Annual Report, 1 December 1984 - 31 December 1985

Description: The ablative, fast pyrolysis system was relocated to SERI's new, permanent Field Test Laboratory. Pyrolysis system modifications were made to increase the energy available to the vortex reactor and to enhance the collection efficiency of primary pyrolysis vapors. Mathematical modeling of the vapor cracker has resulted in the ability to accurately predict experimental results with respect to the thermal cracking of the primary vapors, the generation of noncondensible gases, and the gas composition. The computer algorithm of this model can be readily used to perform experimental simulation and/or reactor scale-up due to its fundamental nature. Preliminary screening tests with pure ZSM-5 zeolite catalyst, supplied by Mobil Research and Development Corporation, have shown promise for the conversion of primary pyrolysis oil vapors to aromatic hydrocarbons; i.e., gasoline.
Date: July 1, 1986
Creator: Diebold, J. P.; Scahill, J. W. & Evans, R. J.
Partner: UNT Libraries Government Documents Department

Fundamental Pyrolysis Studies

Description: Progress on the direct mass spectrometric sampling of pyrolysis products from wood and its constituents is described for the period from June 1982 to February 1983. A brief summary and references to detailed reports, of the qualitative demonstration of our approach to the study of the separated processes of primary and secondary pyrolysis is presented. Improvements and additions to the pyrolysis and data acquisition systems are discussed and typical results shown. Chief of these are a heated-grid pyrolysis system for controlled primary pyrolysis and a sheathed flame arrangement for secondary cracking studies. Qualitative results of the secondary cracking of cellulose, lignin, and wood are shown as are comparisons with the literature for the pyrolysis spectra of cellulose, lignin, and levoglucosan. 'Fingerprints' for a number of materials are shown, with spectra taken under carefully controlled conditions so that sensitivity calibrations for different compounds, now being determined, can be applied.
Date: March 1, 1983
Creator: Milne, T. A.; Evans, R. J. & Soltys, M. N.
Partner: UNT Libraries Government Documents Department

Applications of Passive Thin Films

Description: The physical properties of thin films affect the performance and durability of nearly every solar energy conversion device. Familiar examples of thin films for solar applications are optical materials and protective coatings. Optimized optical properties are key to cost-effective photothermal conversion where individual components must have high absorptance, reflectance, or transmittance. The protection of sensitive substrates from corrosion and/or erosion is essential to ensure adequate component and system lifetime. Such substrates range from photovoltaic materials operating near room temperature to turbine blade structural alloys in hostile environments at very high temperatures (>1,000 degrees C). Although much has been written on particular categories of thin-film materials for solar energy (for example, absorbers for receiver surfaces), to date no one has provided an overview of the spectrum of applications for passive thin films in solar energy. This work is such an overview and also reviews the material state of the art as described in the current literature. Active thin film devices such as photovoltaics and thermoeleetrics are not discussed.
Date: May 1, 1979
Creator: Call, P. J.
Partner: UNT Libraries Government Documents Department

U.S. Department of Energy Hydogen and Fuel Cells Program Annual Review/Report: 2011

Description: This document summarizes the comments provided by peer reviewers on hydrogen and fuel cell projects presented at the FY 2011 U.S. Department of Energy (DOE) Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting (AMR), held May 9-13, 2011 in Arlington, Virginia
Date: September 2011
Creator: Satypal, S.
Partner: UNT Libraries Government Documents Department

Photovoltaic Module Reliability Workshop 2010: February 18-19, 2010

Description: NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.
Date: November 1, 2013
Creator: Kurtz, J.
Partner: UNT Libraries Government Documents Department

Photovoltaic Module Reliability Workshop 2011: February 16-17, 2011

Description: NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.
Date: November 1, 2013
Creator: Kurtz, S.
Partner: UNT Libraries Government Documents Department

Photovoltaic Module Reliability Workshop 2013: February 26-27, 2013

Description: NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.
Date: October 1, 2013
Creator: Kurtz, S.
Partner: UNT Libraries Government Documents Department

Photovoltaic Module Reliability Workshop 2012: February 28 - March 1, 2012

Description: NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.
Date: November 1, 2013
Creator: Kurtz, S.
Partner: UNT Libraries Government Documents Department

Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbons: Dilute-Acid and Enzymatic Deconstruction of Biomass to Sugars and Biological Conversion of Sugars to Hydrocarbons

Description: This report describes one potential conversion process to hydrocarbon products by way of biological conversion of lingnocellulosic-dervied sugars. The process design converts biomass to a hydrocarbon intermediate, a free fatty acid, using dilute-acid pretreatement, enzymatic saccharification, and bioconversion. Ancillary areas--feed handling, hydrolysate conditioning, product recovery and upgrading (hydrotreating) to a final blendstock material, wastewater treatment, lignin combusion, and utilities--are also included in the design.
Date: October 1, 2013
Creator: Davis, R.; Tao, L.; Tan, E. C. D.; Biddy, M. J.; Beckham, G. T.; Scarlata, C. et al.
Partner: UNT Libraries Government Documents Department

Production of Advanced Biofuels via Liquefaction - Hydrothermal Liquefaction Reactor Design: April 5, 2013

Description: This report provides detailed reactor designs and capital costs, and operating cost estimates for the hydrothermal liquefaction reactor system, used for biomass-to-biofuels conversion, under development at Pacific Northwest National Laboratory. Five cases were developed and the costs associated with all cases ranged from $22 MM/year - $47 MM/year.
Date: November 1, 2013
Creator: Knorr, D.; Lukas, J. & Schoen, P.
Partner: UNT Libraries Government Documents Department

Computational Fluid Dynamics Analysis of Flexible Duct Junction Box Design

Description: IBACOS explored the relationships between pressure and physical configurations of flexible duct junction boxes by using computational fluid dynamics (CFD) simulations to predict individual box parameters and total system pressure, thereby ensuring improved HVAC performance. Current Air Conditioning Contractors of America (ACCA) guidance (Group 11, Appendix 3, ACCA Manual D, Rutkowski 2009) allows for unconstrained variation in the number of takeoffs, box sizes, and takeoff locations. The only variables currently used in selecting an equivalent length (EL) are velocity of air in the duct and friction rate, given the first takeoff is located at least twice its diameter away from the inlet. This condition does not account for other factors impacting pressure loss across these types of fittings. For each simulation, the IBACOS team converted pressure loss within a box to an EL to compare variation in ACCA Manual D guidance to the simulated variation. IBACOS chose cases to represent flows reasonably correlating to flows typically encountered in the field and analyzed differences in total pressure due to increases in number and location of takeoffs, box dimensions, and velocity of air, and whether an entrance fitting is included. The team also calculated additional balancing losses for all cases due to discrepancies between intended outlet flows and natural flow splits created by the fitting. In certain asymmetrical cases, the balancing losses were significantly higher than symmetrical cases where the natural splits were close to the targets. Thus, IBACOS has shown additional design constraints that can ensure better system performance.
Date: December 1, 2013
Creator: Beach, R.; Prahl, D. & Lange, R.
Partner: UNT Libraries Government Documents Department

Cost-Benefit Analysis of Flexibility Retrofits for Coal and Gas-Fueled Power Plants: August 2012 - December 2013

Description: High penetrations of wind and solar power plants can induce on/off cycling and ramping of fossil-fueled generators. This can lead to wear-and-tear costs and changes in emissions for fossil-fueled generators. Phase 2 of the Western Wind and Solar Integration Study (WWSIS-2) determined these costs and emissions and simulated grid operations to investigate the full impact of wind and solar on the fossil-fueled fleet. This report studies the costs and benefits of retrofitting existing units for improved operational flexibility (i.e., capability to turndown lower, start and stop faster, and ramp faster between load set-points).
Date: December 1, 2013
Creator: Venkataraman, S.; Jordan, G.; O'Connor, M.; Kumar, N.; Lefton, S.; Lew, D. et al.
Partner: UNT Libraries Government Documents Department

First International Workshop on Grid Simulator Testing of Wind Turbine Drivetrains: Workshop Proceedings

Description: This report summarizes the proceedings of the First International Workshop on Grid Simulator Testing of Wind Turbine Drivetrains, held from June 13 to 14, 2013, at the National Renewable Energy Laboratory's National Wind Technology Center, located south of Boulder, Colorado. The workshop was sponsored by the U.S. Department of Energy and cohosted by the National Renewable Energy Laboratory and Clemson University under ongoing collaboration via a cooperative research and development agreement. The purpose of the workshop was to provide a forum to discuss the research, testing needs, and state-of-the-art apparatuses involved in grid compliance testing of utility-scale wind turbine generators. This includes both dynamometer testing of wind turbine drivetrains ('ground testing') and field testing grid-connected wind turbines. Four sessions followed by discussions in which all attendees of the workshop were encouraged to participate comprised the workshop.
Date: November 1, 2013
Creator: Gevorgian, V.; Link, H.; McDade, M.; Mander, A.; Fox, J. C. & Rigas, N.
Partner: UNT Libraries Government Documents Department

Executive Order 13514: Federal Leadership in Environmental, Energy, and Economic Performance; Comprehensive Federal Fleet Management Handbook (Book)

Description: A comprehensive Federal Fleet Management Handbook that builds upon the "Guidance for Federal Agencies on E.O. 13514 Section 12-Federal Fleet Management" and provides information to help fleet managers select optimal greenhouse gas and petroleum reduction strategies for each location, meeting or exceeding related fleet requirements, acquiring vehicles to support these strategies while minimizing fleet size and vehicle miles traveled, and refining strategies based on agency performance.
Date: January 1, 2014
Creator: Daley, R.; Ahdieh, N. & Bentley, J.
Partner: UNT Libraries Government Documents Department

Safety and Function Test Report for the Viryd CS8 Wind Turbine

Description: This test was conducted as part of the U.S. Department of Energy's (DOE) Independent Testing project. This project was established to help reduce the barriers of wind energy expansion by providing independent testing results for small turbines. Several turbines were selected for testing at the National Wind Technology Center (NWTC) at the National Renewable Energy Laboratory (NREL) as a part of the Small Wind Turbine Independent Testing project. Safety and function testing is one of up to five tests that may be performed on the turbines. Other tests include duration, power performance, acoustic noise, and power quality. Viryd Technologies, Inc. of Austin, Texas, was the recipient of the DOE grant and provided the turbine for testing.
Date: October 1, 2013
Creator: Roadman, J.; Murphy, M. & van Dam, J.
Partner: UNT Libraries Government Documents Department

Regulatory Considerations Associated with the Expanded Adoption of Distributed Solar

Description: Increased adoption of distributed PV, and other forms of distributed generation, have the potential to affect utility-customer interactions, system costs recovery, and utility revenue streams. If a greater number of electricity customers choose to self-generate, demand for system power will decrease and utility fixed costs will have to be recovered over fewer kilowatt hours of sales. As such, regulators will need to determine the value and cost of additional distributed PV and determine the appropriate allocation of the costs and benefits among consumers. The potential for new business models to emerge also has implications for regulation and rate structures that ensure equitable solutions for all electricity grid users. This report examines regulatory tools and rate designs for addressing emerging issues with the expanded adoption of distributed PV and evaluates the potential effectiveness and viability of these options going forward. It offers the groundwork needed in order for regulators to explore mechanisms and ensure that utilities can collect sufficient revenues to provide reliable electric service, cover fixed costs, and balance cost equity among ratepayers -- while creating a value proposition for customers to adopt distributed PV.
Date: November 1, 2013
Creator: Bird, L.; McLaren, J.; Heeter, J.; Linvill, C.; Shenot, J.; Sedano, R. et al.
Partner: UNT Libraries Government Documents Department

Hydrogen Pathways: Updated Cost, Well-to-Wheels Energy Use, and Emissions for the Current Technology Status of Ten Hydrogen Production, Delivery, and Distribution Scenarios

Description: This report describes a life-cycle assessment conducted by the National Renewable Energy Laboratory (NREL) of 10 hydrogen production, delivery, dispensing, and use pathways that were evaluated for cost, energy use, and greenhouse gas (GHG) emissions. This evaluation updates and expands on a previous assessment of seven pathways conducted in 2009. This study summarizes key results, parameters, and sensitivities to those parameters for the 10 hydrogen pathways, reporting on the levelized cost of hydrogen in 2007 U.S. dollars as well as life-cycle well-to-wheels energy use and GHG emissions associated with the pathways.
Date: March 1, 2013
Creator: Ramsden, T.; Ruth, M.; Diakov, V.; Laffen, M. & Timbario, T. A.
Partner: UNT Libraries Government Documents Department

Hydrotreating Pyrolytic Lignin to Produce a Refinery Feedstock (Poster)

Description: Fast pyrolysis of biomass followed by water separation to produce pyrolytic lignin and hydrotreating of the lignin could be used to produce a stable volatile low-oxygen intermediate liquid. Such a liquid could be converted into a finished motor-fuel in a refinery, taking advantage of the existing infrastructure and economies of scale of refineries. Hydrotreating just the lignin would consume less hydrogen while preserving about half of the energy of the original oil. The aqueous by-products could be reformed to produce the needed hydrogen and would contain much of the unwanted acids and unstable oxygenates. To assess such intermediate liquids, several pyrolytic lignins were prepared by mixing pyrolysis oil with water at 1:1 and 3:1 ratios. The carboxylic acidity in the pyrolytic lignin was reduced to 24 and 10 mg-KOH/g-lignin compared to 81 in the whole oil. These lignins were hydrotreated using Ni-Mo(S)/alumina, Pt/char, or Pd/C(activated) in a semi-batch 1 L stirred autoclave. The oil was stabilized under hydrogen at 150-280 degrees C, then water and light organics were removed by partial depressurization. Hydrodeoxygenation was then performed at 340-400 degrees C. Total pressure was controlled at 70 or 170 bar with hydrogen gas. Organic liquid yields of 39-56% were obtained. For many experiments the organic oxygen content was <7%, acidity was < 7 mg-KOH/g-oil, the volatility was greater than or equal to 94% and, on a carbon basis, the total yield of organic products miscible in hydrocarbons at a 1:10 ratio was over 50%. These properties are probably acceptable to a refinery.The residual liquids left in the reactor at the end of the experiment comprised 60-85% of the organic-phase product while the rest was condensate. 13C-NMR of the residual liquids showed that they were 50-80% aliphatic. 13C-NMR coupled with GC-MS identified phenolic compounds as the main oxygenates in most residual liquids.
Date: September 1, 2013
Creator: French, R. J.
Partner: UNT Libraries Government Documents Department

Cladding Attachment Over Thick Exterior Insulating Sheathing

Description: The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of both wood framed walls as well as mass masonry wall assemblies. For thick layers of exterior insulation (levels greater than 1.5 inches), the use of wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location (Straube and Smegal 2009, Pettit 2009, Joyce 2009, Ueno 2010). The research presented in this report is intended to help develop a better understanding of the system mechanics involved and the potential for environmental exposure induced movement between the furring strip and the framing. BSC sought to address the following research questions: 1. What are the relative roles of the mechanisms and the magnitudes of the force that influence the vertical displacement resistance of the system? 2. Can the capacity at a specified deflection be reliably calculated using mechanics based equations? 3. What are the impacts of environmental exposure on the vertical displacement of furring strips attached directly through insulation back to a wood structure?
Date: January 1, 2014
Creator: Baker, P.; Eng, P. & Lepage, R.
Partner: UNT Libraries Government Documents Department

10 MW Supercritical CO2 Turbine Test

Description: The Supercritical CO2 Turbine Test project was to demonstrate the inherent efficiencies of a supercritical carbon dioxide (s-CO2) power turbine and associated turbomachinery under conditions and at a scale relevant to commercial concentrating solar power (CSP) projects, thereby accelerating the commercial deployment of this new power generation technology. The project involved eight partnering organizations: NREL, Sandia National Laboratories, Echogen Power Systems, Abengoa Solar, University of Wisconsin at Madison, Electric Power Research Institute, Barber-Nichols, and the CSP Program of the U.S. Department of Energy. The multi-year project planned to design, fabricate, and validate an s-CO2 power turbine of nominally 10 MWe that is capable of operation at up to 700°C and operates in a dry-cooled test loop. The project plan consisted of three phases: (1) system design and modeling, (2) fabrication, and (3) testing. The major accomplishments of Phase 1 included: Design of a multistage, axial-flow, s-CO2 power turbine; Design modifications to an existing turbocompressor to provide s-CO2 flow for the test system; Updated equipment and installation costs for the turbomachinery and associated support infrastructure; Development of simulation tools for the test loop itself and for more efficient cycle designs that are of greater commercial interest; Simulation of s-CO2 power cycle integration into molten-nitrate-salt CSP systems indicating a cost benefit of up to 8% in levelized cost of energy; Identification of recuperator cost as a key economic parameter; Corrosion data for multiple alloys at temperatures up to 650ºC in high-pressure CO2 and recommendations for materials-of-construction; and Revised test plan and preliminary operating conditions based on the ongoing tests of related equipment. Phase 1 established that the cost of the facility needed to test the power turbine at its full power and temperature would exceed the planned funding for Phases 2 and 3. Late in Phase 1 an opportunity arose to collaborate ...
Date: January 29, 2014
Creator: Turchi, Craig
Partner: UNT Libraries Government Documents Department

Multifamily Building Operator Job/Task Analysis and Report: September 2013

Description: The development of job/task analyses (JTAs) is one of three components of the Guidelines for Home Energy Professionals project and will allow industry to develop training resources, quality assurance protocols, accredited training programs, and professional certifications. The Multifamily Building Operator JTA identifies and catalogs all of the tasks performed by multifamily building operators, as well as the knowledge, skills, and abilities (KSAs) needed to perform the identified tasks.
Date: September 1, 2013
Creator: Owens, C. M.
Partner: UNT Libraries Government Documents Department