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Western Wind and Solar Integration Study: Phase 2 [Presentation]

Description: This presentation summarizes the scope and results of the Western Wind and Solar Integration Study Phase 2, which examined operational impacts of high penetrations of variable renewable generation in the West.
Date: September 1, 2013
Creator: Lew, D.; Brinkman, G.; Ibanez, E.; Lefton, S.; Kumar, N.; Venkataraman, S. et al.
Partner: UNT Libraries Government Documents Department

Understanding the Temperature and Humidity Environment Inside a PV Module [Presentation]

Description: This presentation addresses moisture-driven degradation processes in PV modules and the conditions to use for accelerated stress testing. Here we show that by choosing humidity conditions that more closely match the use environment, one can minimize the uncertainty associated with moisture induced degradation modes.
Date: June 1, 2013
Creator: Kempe, M.
Partner: UNT Libraries Government Documents Department

Plasma-Material Interface Development for Future Spherical Tokamak-based Devices in NSTX.

Description: The divertor plasma-material interface (PMI) must be able to withstand steady-state heat fluxes up to 10 MW/m{sup 2} (a limit imposed by the present day divertor material and engineering constraints) with minimal material erosion, as well as to provide impurity control and ion density pumping capabilities. In spherical tokamaks (STs), the compact divertor geometry and the requirement of low core electron collisionality n*{sub e} at n{sub e} < 0.5-0.7 n{sub G} (where n{sub G} is the Greenwald density) for increased neutral beam current drive efficiency impose much greater demands on divertor and first-wall particle and heat flux mitigation solutions. In NSTX, divertor heat flux mitigation and impurity control with an innovative 'snowflake' divertor configuration and ion density pumping by evaporated lithium wall and divertor coatings are studied. Lithium coatings have enabled ion density reduction up to 50% in NSTX through the reduction of wall and divertor recycling rates. The 'snowflake' divertor configuration was obtained in NSTX in 0.8-1 MA 4-6 MW NBI-heated H-mode lithium-assisted discharges using three divertor coils. The snowflake divertor formation was always accompanied by a partial detachment of the outer strike point with an up to 50% increase in divertor radiation from intrinsic carbon, the peak divertor heat flux reduction from 3-6 MW/m{sup 2} to 0.5-1 MW/m{sup 2}, and a significant increase in divertor volume recombination. High core confinement was maintained with the snowflake divertor, evidenced by the t{sub E}, W{sub MHD} and the H98(y,2) factors similar to those of the standard divertor discharges. Core carbon concentration and radiated power were reduced by 30-70%, apparently as a result of reduced divertor physical and chemical sputtering in the snowflake divertor and ELMs. In the SFD discharges, the MHD stability of the H-mode pedestal region was altered leading to the re-appearance of medium size (DW/W = 5-10%), Type I, ...
Date: September 24, 2011
Creator: Soukhanovskii, V. A.; Battaglia, D.; Bell, M G.; Bell, R. E.; Diallo, A.; Gerhardt, S. et al.
Partner: UNT Libraries Government Documents Department

Hydrogen Technology Validation as a "Learning Demonstration" that Feeds the R&D Process (Presentation)

Description: This presentation, which provides information about how hydrogen technology validation is used as a learning demonstration that feeds the research and development process, was given at a National Hydrogen Association meeting in April 2004.
Date: April 1, 2004
Creator: Wipke, K.; Gronich, S. & Hooker, D.
Partner: UNT Libraries Government Documents Department

Fuel Cell Technology Status - Voltage Degradation [Presentation]

Description: This presentation describes an independent assessment of fuel cell durability status and discusses the project's relevance to the Department of Energy Hydrogen and Fuel Cells Program; NREL's analysis approach; the FY12 technical accomplishments including the fourth annual publication of results; and project collaborations and future work.
Date: June 1, 2012
Creator: Kurtz, J.; Wipke,; Sprik, S. & Saur, G.
Partner: UNT Libraries Government Documents Department

Testing Active Power Control from Wind Power at the National Wind Technology Center (NWTC) [Presentation]

Description: In order to keep the electricity grid stable and the lights on, the power system relies on certain responses from its generating fleet. This presentation evaluates the potential for wind turbines and wind power plants to provide these services and assist the grid during critical times.
Date: May 1, 2011
Creator: Ela, E.
Partner: UNT Libraries Government Documents Department

Durability of Polymeric Encapsulation Materials for Concentrating Photovoltaic Systems [Poster]

Description: Polymeric encapsulation materials are typically used in concentrating photovoltaic (CPV) modules to protect the cell from the field environment. Because it is physically located adjacent to the cell, the encapsulation is exposed to a high optical flux, often including light in the ultraviolet (UV) and infrared (IR) wavelengths. The durability of encapsulants used in CPV modules is critical to the technology, but is presently not well understood. This work seeks to identify the appropriate material types, field-induced failure mechanisms, and factors of influence (if possible) of polymeric encapsulation. These results will ultimately be weighed against those of future qualification and accelerated life test procedures.
Date: February 1, 2011
Creator: Miller, D. C.; Kempe, M. D.; Araki, K.; Kennedy, C. E. & Kurtz, S. R.
Partner: UNT Libraries Government Documents Department

Parabolic Trough Receiver Heat Loss Testing (Poster)

Description: Parabolic trough receivers, or heat collection elements (HCEs), absorb sunlight focused by the mirrors and transfer that thermal energy to a fluid flowing within them. Thje absorbing tube of these receivers typically operates around 400 C (752 F). HCE manufacturers prevent thermal loss from the absorbing tube to the environment by using sputtered selective Cermet coatings on the absorber and by surrounding the absorber with a glass-enclosed evacuated annulus. This work quantifies the heat loss of the Solel UVAC2 and Schott PTR70 HCEs. At 400 C, the HCEs perform similarly, losing about 400 W/m of HCE length. To put this in perspective, the incident beam radiation on a 5 m mirror aperture is about 4500 W/m, with about 75% of that energy ({approx} 3400 W/m) reaching the absorber surface. Of the 3400 W/m on the absorber, about 3000 W/m is absorbed into the working fluid while 400 W/m is lost to the environment.
Date: March 1, 2007
Creator: Price, H.; Netter, J.; Bingham, C.; Kutscher, C.; Burkholder, F. & Brandemuehl, M.
Partner: UNT Libraries Government Documents Department

Material Resource Considerations for Ex Situ Carbon Sequestration

Description: The conclusions of this report are: (1) There are enough ultramafic resources to sequester all the CO{sub 2} produced by coal-fired powerplants in the US; (2) Sequestering all the CO{sub 2} would require a significant increase in the mining of ultramafic minerals; (3) The increased mining will have an environmental cost; (4) Some man made by product minerals could contribute to CO{sub 2} sequestration although many of these resources are small; and (5) It may be possible in some cases to sequester CO{sub 2} and eliminate hazardous waste in the same ex situ process.
Date: May 1, 2005
Creator: Gerdemann, Stephen J.; Dahlin, David C.; O'Connor, William K.; Penner, Larry R. & Rush, Gilbert E.
Partner: UNT Libraries Government Documents Department

Electrochemical noise sensors for detection of localized and general corrosion of natural gas transmission pipelines

Description: The U.S. Department of Energy, National Energy Technology Laboratory funded a Natural Gas Infrastructure Reliability program directed at increasing and enhancing research and development activities in topics such as remote leak detection, pipe inspection, and repair technologies and materials. The Albany Research Center (ARC), U.S. Department of Energy was funded to study the use of electrochemical noise sensors for detection of localized and general corrosion of natural gas transmission pipelines. As part of this, ARC entered into a collaborative effort with the corrosion sensor industry to demonstrate the capabilities of commercially available remote corrosion sensors for use with the Nation's Gas Transmission Pipeline Infrastructure needs. The goal of the research was to develop an emerging corrosion sensor technology into a monitor for the type and degree of corrosion occurring at key locations in gas transmission pipelines.
Date: September 1, 2002
Creator: Holcomb, Gordon R.; Bullard, Sophie J.; Covino, Bernard S., Jr.; Cramer, Stephen D.; Russell, James H. & Ziomek-Moroz, Margaret
Partner: UNT Libraries Government Documents Department