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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,405 records · Page 78

Blending Hydrogen into Natural Gas Pipeline Networks: A Review of Key Issues

The United States has 11 distinct natural gas pipeline corridors: five originate in the Southwest, four deliver natural gas from Canada, and two extend from the Rocky Mountain region. This study assesses the potential to deliver hydrogen through the existing natural gas pipeline network as a hydrogen and natural gas mixture to defray the cost of building dedicated hydrogen pipelines.

03 NATURAL GAS↗

SAM Technical Review Committee Final Report: Summary and Key Recommendations from the Onsite TRC Meeting Held April 22-23, 2013

The System Advisor Model (SAM) is a broad and robust set of models and frameworks for analyzing both system performance and system financing. It does this across a range of technologies dominated by solar technologies including photovoltaics (PV) and concentrated solar power (CSP). The U.S. Department of Energy (DOE) Solar Energy Technology Program requested the SAM development team to review the photovoltaic performance modeling with the development community and specifically, with the independent engineering community. The report summarizes the major effort for this technical review committee (TRC).

14 SOLAR ENERGY↗

The Use of MOX Fuel in the United States: Bibliography of Important Documents and Discussion of Key Issues

Although this paper provides a short history and discussion of some of the important issues pertaining to WG-MOX, the primary focus of the paper is to provide a useful bibliography of resources pertaining to weapons-grade MOX fuel use in LWRs. Therefore, not all aspects of MOX use were reviewed in this paper. Sandia National Laboratory and other investigators have performed significant work in the United States on severe accident source terms for MOX fuel cycles in comparison with LEU fuel cycles. Sandia’s source term reports indicate that due to some off-setting factors, the actual source terms between MOX and LEU are not significantly different despite the inventory differences. However, those source terms were not used to perform an explicit consequence evaluation to draw a conclusion on the overall integrated risk. Even though there are inventory differences and there is the potential for differences in the source term for MOX fuel, the overall uncertainties in the accident progression, fission product release/retention, source term and risk analyses would indicate that there is no significant difference between MOX and LEU fuel. In addition, recent research shows that current guidelines for fission product release (NUREG-1465) are significantly conservative (by a factor of 2). The National Academy of Sciences has stated: “We believe, further, that under these circumstances no important overall adverse impact of MOX use on the accident probabilities of the LWRs [light water reactors] involved will occur, if there are adequate reactivity and thermal margins in the fuel, as licensing review should ensure, the main remaining determinants of accident probabilities will involve facts not related to fuel composition and hence unaffected by the use of MOX rather than LEU Fuel (NAS, 1995).”

Bevard, Bruce Balkcom↗

Capricious Cables: Understanding the Key Concepts in Transmission Expansion Planning and Its Models

The extra-high-voltage transmission network is the bulk transport network of the electric power system. To understand how the future power system may react to planning decisions today, wide-area transmission models are increasingly used to aid decision makers and stakeholders. The goal of this work is to illuminate these models for a broader audience that may include policy makers or relative newcomers to the field of transmission planning. This paper explains the basic transmission expansion planning model formulation. It highlights six of the major simplifications made in transmission expansion planning models and the resulting need to contextualize model results using knowledge from other models and knowledge not captured in the modeling process.

14 SOLAR ENERGY↗

A Comprehensive System of Energy Intensity Indicators for the U.S.: Methods, Data and Key Trends

This report describes a comprehensive system of energy intensity indicators for the United States that has been developed for the Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE) over the past decade. This system of indicators is hierarchical in nature, beginning with detailed indexes of energy intensity for various sectors of the economy, which are ultimately aggregated to an overall energy intensity index for the economy as a whole. The aggregation of energy intensity indexes to higher levels in the hierarchy is performed with a version of the Log Mean Divisia Index (LMDI) method. Based upon the data and methods in the system of indicators, the economy-wide energy intensity index shows a decline of about 14% in 2010 relative to a 1985 base year. Discussion of energy intensity indicators for each of the broad end-use sectors of the economy—residential, commercial, industrial, and transportation—is presented in the report. An analysis of recent changes in the efficiency of electricity generation in the U.S. is also included. A detailed appendix describes the data sources and methodology behind the energy intensity indicators for each sector.

Belzer, David B.↗

Key Laser Technologies for X-Ray FELs

In the final project period, we demonstrated sub femtosecond timing distribution over a 1.2 km polarization-maintaining (PM) fiber-optic link using balanced optical cross-correlators (BOCs) for link stabilization. By eliminating polarization mode dispersion, link operation for 16 days maintained 0.6 fs RMS timing drift and during a 3-day interval only 0.13 fs drift, which corresponds to a stability level of 10-21. To improve the overall system efficiency and robustness, we developed fiber-coupled, hybrid-integrated BOCs using waveguides in periodically-poled KTiOPO4 (PPKTP). The measured second-harmonic conversion efficiency in the waveguides is a factor of 50 higher than that of bulk-optic crystals. Characterization of 1st-generation devices shows performance comparable to free-space BOCs, with the potential for significant improvement in future devices. For optical-to-RF conversion, we developed two balanced optical-microwave phase detectors (BOM-PD) based on the Sagnac and Mach-Zehnder interferometers. RF extraction using BOM-PDs in phase-locked loops yielded sub-10-fs residual timing jitter for locking bandwidths on the order of several hundred kHz. Finally, we characterized the timing jitter of ultralow-noise Ti:Sapphire oscillators, demonstrating an unprecedented 13 as of jitter integrated over the entire Nyquist band. Our measurements agreed well with theory, confirming our models for quantum-limited laser noise. Measurements of commercially available solid-state lasers at 1550 nm showed that there are laser sources already available with sufficiently low noise to achieve sub-femtosecond performance as master oscillators within a timing distribution system.

42 ENGINEERING↗

Identifying Key Proteins in Hg Methylation Pathways of Desulfovibrio by Global Proteomics (Final Report)

Hg is a wide-spread contaminant in the environment and is toxic in all of its various forms. Organomercurials (RHg + ) and mercuric ion (Hg 2+ ) directly inactivate proteins by binding to their cysteine or selenocysteine residues. In our previous collaborative project involving the Summers, Miller and Lipton laboratories, we developed a high-throughput, mass spectrometry-based global proteomics approach using the 7 stable isotopes of Hg to identify proteins from phenylmercury-exposed E. coli cells that form stable PhHg-adducts. The two overall objectives of this subsequent collaborative project were (1) to expand our novel organomercury-proteomics capability for use with inorganic ionic (HgX 2 ) exposure and (2) to use this new capability to identify Hg-protein adducts in methylating and non-methylating Desulfovibrio exposed to inorganic ionic HgX 2 and test whether those identified uniquely in methylating bacteria are involved in the methylation pathway. The specific objectives and accomplishments of the Miller lab in this project included: Development of algorithms for analysis of the Hg-proteomic mass spectrometry data to identify and quantify Hg-adducted peptides and other trends in the data.

59 BASIC BIOLOGICAL SCIENCES↗

Benchmark Report on Key Outage Attributes: An Analysis of Outage Improvement Opportunities and Priorities

Advanced Outage Control Center (AOCC), is a multi-year pilot project targeted at Nuclear Power Plant (NPP) outage improvement. The purpose of this pilot project is to improve management of NPP outages through the development of an AOCC that is specifically designed to maximize the usefulness of communication and collaboration technologies for outage coordination and problem resolution activities. This report documents the results of a benchmarking effort to evaluate the transferability of technologies demonstrated at Idaho National Laboratory and the primary pilot project partner, Palo Verde Nuclear Generating Station. The initial assumption for this pilot project was that NPPs generally do not take advantage of advanced technology to support outage management activities. Several researchers involved in this pilot project have commercial NPP experience and believed that very little technology has been applied towards outage communication and collaboration. To verify that the technology options researched and demonstrated through this pilot project would in fact have broad application for the US commercial nuclear fleet, and to look for additional outage management best practices, LWRS program researchers visited several additional nuclear facilities.

99 GENERAL AND MISCELLANEOUS↗

Review and Status of Wind Integration and Transmission in the United States. Key Issues and Lessons Learned

The objective in electric power system operation is to use generation and transmission resources within organizational constraints and operational rules and regulations to reliably and costeffectively balance load and generation. To meet this objective, system operational practices have been created to accommodate the innate variability and uncertainty that comes from a variety of sources, such as uncertainty of demand forecasts, whether a specific generating unit will be available when called upon, the variability of demand from many different types of customers, and others. As more wind power is connected to the power system, operating experiences acquired during the past several years have generally confirmed the findings of wind integration studies: wind energy increases the level of variability and uncertainty that a system operator must manage.

17 WIND ENERGY↗

Policies to Support Wind Power Deployment: Key Considerations and Good Practices

Policies have played an important role in scaling up wind deployment and increasing its economic viability while also supporting country-specific economic, social, and environmental development goals. Although wind power has become cost-competitive in several contexts, challenges to wind power deployment remain. Within the context of country-specific goals and challenges, policymakers are seeking

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Expert Meeting Report: Key Innovations for Adding Energy Efficiency to Maintenance Projects

This report describes an expert meeting hosted by the Building America research team NAHB Research Center, which was held on February 8, 2012, in Orlando, Florida. The topic focused on efforts to increase the efficiency of existing homes, specifically for re-roofing and the opportunities for adding energy efficiency upgrades during this major home repair activity.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Blending Hydrogen into Natural Gas Pipeline Networks: A Review of Key Issues

This study assesses the potential to deliver hydrogen through the existing natural gas pipeline network as a hydrogen and natural gas mixture to defray the cost of building dedicated hydrogen pipelines. Blending hydrogen into the existing natural gas pipeline network has also been proposed as a means of increasing the output of renewable energy systems such as large wind farms.

03 NATURAL GAS↗

Advancement of Systems Designs and Key Engineering Technologies for Materials Based Hydrogen Storage

UTRC lead the development of the Simulink Framework model that enables a comparison of different hydrogen storage systems on a common basis. The Simulink Framework model was disseminated on the www.HSECoE.org website that is hosted by NREL. UTRC contributed to a better understanding of the safety aspects of the proposed hydrogen storage systems. UTRC also participated in the Failure Mode and Effect Analysis of both the chemical- and the adsorbent-based hydrogen storage system during Phase 2 of the Hydrogen Storage Engineering Center of Excellence. UTRC designed a hydrogen storage system with a reversible metal hydride material in a compacted form for light-duty vehicles with a 5.6 kg H2 storage capacity, giving it a 300 miles range. It contains a heat exchanger that enables efficient cooling of the metal hydride material during hydrogen absorption in order to meet the 3.3 minute refueling time target. It has been shown through computation that the kinetics of hydrogen absorption of Ti-catalyzed NaAlH4 was ultimately limiting the rate of hydrogen absorption to 85% of the material capacity in 3.3 minutes. An inverse analysis was performed in order to determine the material property requirements in order for a metal hydride based hydrogen storage system to meet the DOE targets. Work on metal hydride storage systems was halted after the Phase 1 to Phase 2 review due to the lack of metal hydride materials with the required material properties. UTRC contributed to the design of a chemical hydrogen storage system by developing an adsorbent for removing the impurity ammonia from the hydrogen gas, by developing a system to meter the transport of Ammonia Borane (AB) powder to a thermolysis reactor, and by developing a gas-liquid-separator (GLS) for the separation of hydrogen gas from AB slurry in silicone oil. Stripping impurities from hydrogen gas is essential for a long life of the fuel cell system on board of a vehicle. Work on solid transport of AB was halted after the Phase 1 to Phase 2 review in favor of studying the slurry-form of AB as it appeared to be difficult to transport a solid form of AB through the thermolysis reactor. UTRC demonstrated the operation of a compact GLS in the laboratory at a scale that would be required for the actual automotive application. The GLS met the targets for weight and volume. UTRC also reported about the unresolved issue associated with the high vapor pressure of fluids that could be used for making a slurry-form of AB. Work on the GLS was halted after the Phase 2 to Phase 3 review as the off-board regeneration efficiency of the spent AB was below the DOE target of 60%. UTRC contributed to the design of an adsorbent-based hydrogen storage system through measurements of the thermal conductivity of a compacted form of Metal Organic Framework (MOF) number 5 and through the development and sizing of a particulate filter. Thermal conductivity is important for the design of the modular adsorbent tank insert (MATI), as developed by Oregon State University (OSU), in order to enable a rapid refueling process. Stringent hydrogen quality requirements can only be met with an efficient particulate filtration system. UTRC developed a method to size the particulate filter by taking into account the effect of the pressure drop on the hydrogen adsorption process in the tank. UTRC raised awareness about the potential use of materials-based H2 storage systems in applications outside the traditional light-duty vehicle market segment by presenting at several conferences about niche application opportunities in Unmanned Aerial Vehicles (UAV), Autonomous Underwater Vehicles (AUV), portable power and others.

08 HYDROGEN↗

Key Factors for Determining Risk of Groundwater Impacts Due to Leakage from Geologic Carbon Sequestration Reservoirs

The National Risk Assessment Partnership (NRAP) is developing a science-based toolset for the analysis of potential impacts to groundwater chemistry from CO 2 injection (www.netldoe.gov/nrap). The toolset adopts a stochastic approach in which predictions address uncertainties in shallow underwater and leakage scenarios. It is derived from detailed physics and chemistry simulation results that are used to train more computationally efficient models,l referred to here as reduced-order models (ROMs), for each component system. In particular, these tools can be used to help regulators and operators understand the expected sizes and longevity of plumes in pH, TDS, and dissolved metals that could result from a leakage of brine and/or CO 2 from a storage reservoir into aquifers. This information can inform, for example, decisions on monitoring strategies that are both effective and efficient. We have used this approach to develop predictive reduced-order models for two common types of reservoirs, but the approach could be used to develop a model for a specific aquifer or other common types of aquifers. In this paper we describe potential impacts to groundwater quality due to CO 2 and brine leakage, discuss an approach to calculate thresholds under which "no impact" to groundwater occurs, describe the time scale for impact on groundwater, and discuss the probability of detecting a groundwater plume should leakage occur.

54 ENVIRONMENTAL SCIENCES↗