bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of Energy Storage Methods for Solar Electric Production
Authors: Shakeri Mostafa , Soltanzadeh Maryam , Berson R. Eric , Sharp M. Keith 
Published: October 2014

Energy storage is key to expanding the capacity factor for electric power from solar energy. To accommodate variable weather patterns and electric demand, storage may be needed not just for diurnal cycles, but for variations as long as seasonal. Five solar electric systems with energy storage were simulated and compared, including an ammonia thermochemical energy storage cycle, compressed air energy storage (CAES), pumped hydroelectric energy storage (PHES), vanadium flow battery, and thermal energy storage (TES). To isolate the influence of the storage system, all systems used the same parabolic concentrator and Stirling engine. For CAES, PHES and battery, the engine directly produced electricity, which was then converted and stored. For TES, heat transfer fluid was heated by the dish and stored, and later used to drive the engine to produce electricity. For ammonia, the dish heated an ammonia dissociation reactor to produce nitrogen and hydrogen, which was stored. Heat was recovered to drive the engine by reforming ammonia from the stored gases. Each system was simulated in TRNSYS with weather data for Louisville, KY and Phoenix, AZ with subsystem efficiencies and storage losses estimated from previous experimental results. All systems including the ammonia cycle involved time dependent storage losses. Losses from the receiver included convection and emitted radiation, both of which depend on receiver temperature.
Overall (solar-storage-electric) efficiency of the ammonia cycle depended strongly on synthesis reactor temperature, ranging from less than 1% to ∼18% for both Louisville, KY and Phoenix, AZ, at 500 K to 800 K, respectively. In contrast, the effect of dissociation reactor temperature was less. Overall (solar-electric-storage-electric) efficiencies of the CAES, systems in the limit of zero storage time ranged from ∼10% to ∼18% for solar receiver temperature of 500 K to 800 K. The vanadium flow battery and PHES efficiencies ranged from ∼9% to ∼17% for the same conditions. TES initially provided 12 to 23% efficiency over the same range of temperature. When time-dependent storage losses were included, however, efficiencies for all systems declined rapidly except the ammonia cycle in both locations and PHES in Louisville. The ammonia system had the highest efficiency after one month of storage, an advantage that increased with time of storage.
The simulations showed that TES was most efficient for diurnal-scale storage and the ammonia cycle for longer storage. Full capacity factor for solar electric production may be most efficiently accomplished with a combination of direct solar-electric production and systems with both diurnal and long-term storage, the proportions of which depending on weather conditions and electric demand profiles.
New Thermal Energy Storage Materials From Industrial Wastes: Compatibility of Steel Slags With the Most Common Heat Transfer Fluids
Authors: Ortega Iñigo , Rodríguez-Aseguinolaza Javier , Gil Antoni , Faik Abdessamad , D’Aguanno Bruno 
Published: October 2014

Slag is one of the main waste materials of the iron and steel manufacturing. Every year about 20 million tons of slag are generated in the United States and 43.5 million tons in Europe. The revalorization of this by-product as heat storage material in thermal energy storage systems would have numerous advantages which include: the possibility to extend the working temperature range up to 1000 °C, the reduction of the system cost and, at the same time, the decrease of the quantity of waste in the iron and steel industry.
In this paper, two different electric arc furnace slags from two companies located in the Basque Country (Spain) are studied. Their thermal stability and compatibility in direct contact with the most common heat transfer fluids used in the concentrated solar power plants are analyzed. The experiments have been designed in order to cover a wide temperature range up to the maximum operation temperature of the future generation of concentrated solar power plants (1000 °C). In particular, three different fluids have been studied: synthetic oil (Syltherm 800®) at 400 °C, molten salt (Solar Salt) at 500 °C and air at 1000 °C. In addition, a complete characterization of the studied slags and fluids used in the experiments is presented showing the behavior of these materials after 500 hour laboratory-tests.
Transport Energy Demand Modeling of the United States Using Artificial Neural Networks and Multiple Linear Regressions
Authors: Kialashaki Arash , Reisel John 
Published: October 2014

In 2009, the transportation sector was the second largest consumer of primary energy in the United States, following the electric power sector and followed by the industrial, residential, and commercial sectors. The pattern of energy use varies by sector. For example, petroleum provides 96% of the energy used for transportation but its share is much less in other sectors. While the United States consumes vast quantities of energy, it has also pledged to cut its greenhouse gas emissions by 2050. In order to assist in planning for future energy needs, the purpose of this study is to develop a model for transport energy demand that incorporates past trends.
This paper describes the development of two types of transportation energy models which are able to predict the United States’ future transportation energy-demand. One model uses an artificial neural network technique (a feed-forward multilayer perceptron neural network coupled with back-propagation technique), and the other model uses a multiple linear regression technique. Various independent variables (including GDP, population, oil price, and number of vehicles) are tested.
The future transport energy demand can then be forecast based on the application of the growth rate of effective parameters on the models. The future trends of independent variables have been predicted based on the historical data from 1980 using a regression method. Using the forecast of independent variables, the energy demand has been forecasted for period of 2010 to 2030.
In terms of the forecasts generated, the models show two different trends despite their performances being at the same level during the model-test period. Although, the results from the regression models show a uniform increase with different slopes corresponding to different models for energy demand in the near future, the results from ANN express no significant change in demand in same time frame. Increased sensitivity of the ANN models to the recent fluctuations caused by the economic recession may be the reason for the differences with the regression models which predict based on the total long-term trends.
Although a small increase in the energy demand in the transportation sector of the United States has been predicted by the models, additional factors need to be considered regarding future energy policy. For example, the United States may choose to reduce energy consumption in order to reduce CO2 emissions and meet its national and international commitments, or large increases in fuel efficiency may reduce petroleum demand.
Optical Properties of Select Particulates After High-Temperature Exposure
Authors: Roop Jonathan , Jeter Sheldon , Abdel-Khalik Said I. , Ho Clifford K. 
Published: October 2014

One increasingly viable option for high temperature concentrator solar power (CSP) is a central receiver system with a particle heating receiver (PHR). A PHR system uses suitable particulates to capture and store energy. It is expected that the particles will be sustained at high temperatures (in the range of 300°C or 400°C to 700°C or 800°C or even 1000°C) on most typical days of plant operation, so there is interest in how the particle optical properties might change after prolonged high-temperature exposure.
This paper presents the results from experiments conducted over a 5-month period in which samples of various types of particulates including silica sands and alumina proppants were exposed to high temperatures for extended periods of time. The reflectance of a bed of particles was measured at room temperature in 8 wavelength bands using the 410-Solar reflectometer device developed by Surface Optics Corporation. The infrared emittance was determined using the ETS-100 emissometer instrument, also developed by Surface Optics Corporation [1,2].
Particles were heated to 950°C and 350°C, and measurements were recorded at intervals during the exposure so that trends in the optical properties over time could be observed. From the measured data, the total solar absorptance and total hemispherical emittance at high temperature were computed; these results are also presented.
Development of High Temperature Liquid Metal Heat Transfer Fluids for CSP Applications
Authors: Warrier Gopinath R. , Ju Y. Sungtaek , Schroers Jan , Asta Mark , Hosemann Peter 
Published: October 2014

In response to the DOE Sunshot Initiative to develop low-cost, high efficiency CSP systems, UCLA is leading a multi-university research effort to develop new high temperature heat transfer fluids capable of stable operation at 800°C and above. Due to their operating temperature range, desirable heat transfer properties and very low vapor pressure, liquid metals were chosen as the heat transfer fluid. An overview of the ongoing research effort is presented.
Development of new liquid metal coolants begins with identification of suitable candidate metals and their alloys. Initial selection of candidate metals was based on such parameters as melting temperature, cost, toxicity, stability/reactivity Combinatorial sputtering of the down selected candidate metals is used to fabricate large compositional spaces (∼ 800), which are then characterized using high-throughput techniques (e.g., X-ray diffraction). Massively parallel optical methods are used to determine melting temperatures. Thermochemical modeling is also performed concurrently to compliment the experimental efforts and identify candidate multicomponent alloy systems that best match the targeted properties. The modeling effort makes use of available thermodynamic databases, the computational thermodynamic CALPHAD framework and molecular-dynamics simulations of molten alloys. Refinement of available thermodynamics models are performed by comparison with available experimental data. Characterizing corrosion in structural materials such as steels, when using liquid metals, and strategies to mitigate them are an integral part of this study. The corrosion mitigation strategy we have adopted is based on the formation of stable oxide layers on the structural metal surface which prevents further corrosion. As such oxygen control is crucial in such liquid metal systems. Liquid metal enhanced creep and embrittlement in commonly used structural materials are also being investigated. Experiments with oxygen control are ongoing to evaluate what structural materials can be used with liquid metals. Characterization of the heat transfer during forced flow is another key component of the study. Both experiments and modeling efforts have been initiated. Key results from experiments and modeling performed over the last year are highlighted and discussed.
Experimental Evaluation of a Water Source CO2 Heat Pump Incorporating Novel Gas-Cooler Configuration
Authors: Murray Portia , Harrison Stephen , Johnson Gary , Stinson Ben 
Published: October 2014

Carbon dioxide’s use as an alternative refrigerant has been increasing in popularity due to its low global warming and ozone depletion potentials. In recent years, a number of companies and researchers have investigated applications of CO2 heat pumps for water heating.
This study investigates the experimental testing of a CO2 heat pump water heater (HPWH) at Queen’s University. For the tests, the conventional factory gas-cooler on an Eco-cute unit and air-source evaporator was replaced with a specially designed brazed-plate gas-cooler. It rejected heat to a 273 litre hot water and the evaporator sourced heat from a warm water supply.
Experiments were conducted using both forced and natural convection (i.e., thermosyphon) flow between the gas-cooler and hot water tank. Thermosyphon flow was studied to evaluate its effects on storage tank stratification and heat pump operation (i.e., coefficient of performance). Results were compared to forced circulation cases run over a range of flow rates.
In the forced convection flow test, it was observed that a decrease in gas-cooler average water temperature increased the coefficient of performance (COP) non-linearly and an increase in the water-side flow rate increased the COP and the effectiveness of the gas-cooler.
The thermosyphon had an average flow rate of 0.75 L/min and an average COP of 3.1. Thermosyphon flow kept the hot water tank fully stratified until fully charged. Water was delivered at an average of 70°C. It was also observed that thermosyphon flow rate depended on the state of charge (i.e., temperature distribution) in the storage tank.
In order to increase the performance, a gas-cooler with a lower pressure drop should be used to increase the thermosyphon flow rate.
Delivering Renewable Integration Services Through University Microgrid Operations: A University of California, San Diego Microgrid Case Study
Authors: Sreedharan Priya , Farbes Jamil , Cutter Eric 
Published: October 2014

Integrating high penetration variable renewables in economically and operationally plausible ways is a current clean energy challenge facing many countries and regions, including California. Renewable energy deployment is a relevant pathway to decarbonize the electricity sector and reduce greenhouse gas emissions (GHGs) and mitigate the harmful effects of climate change. This paper highlights the key findings from a recently completed study, funded by the California Solar Initiative, to develop and investigate strategies to integrate high penetration renewable energy and solar photovoltaic (PV) systems using distributed energy resources (DER). We develop hypothetical operating strategies that utilize the DER present in campus microgrids, such as combined heat and power (CHP) systems and thermal energy storage, and evaluate these based on economic criteria.
Our host site is the University of California, San Diego (UCSD) microgrid, which has a rich DER base that includes a 2.8 MW fuel cell powered by directed biogas, 30 MW of onsite generation, steam and electric chillers, thermal storage and roughly 1.5 MW of onsite solar PV. We develop and evaluate three types of strategies for integrating renewable generation: peak load shifting, on-site PV firming, and grid support. We analyze these strategies with an hourly dispatch optimization model and one year of data. We define a successful renewable integration strategy as one that is operationally plausible and economically viable.
We find all three classes of strategies are technically feasible and can be cost-effective under certain conditions. However, we find that the value proposition to customers such as the UCSD campus, under current tariff structures and market prices, will need to be higher to motivate such customers to offer these services, given the risks associated with changing microgrid operations from regular practice. Our findings suggest alternative incentive mechanisms and engagement strategies beyond those pathways currently available are needed to leverage the potential of DER at campuses for renewables integration purposes. Such efforts are relevant not only to campus resources but to similar commercial and industrial loads across California, including the vast combined heat and power resources.
Process and Lessons-Learned From an Interdisciplinary Collaboration in the Design and Construction of a Net-Zero Energy Solar House
Authors: Azarbayjani Mona , Cecchi Valentina , Tempest Brett 
Published: October 2014

This paper reviews the development process of a net-zero-energy modular house, called UrbanEden, which was the UNC-Charlotte entry to the 2013 US Department of Energy Solar Decathlon competition. It reports the collaboration of students and faculty from various colleges and schools at UNC-Charlotte working towards delivering a net-zero energy house for the competition held in October in Irvine California.
The study presents the participation of students involved in various phases of schematic design, design development and construction. It also identifies the composition and organization of students through the two-year progress and how it evolved throughout the process. The paper also reviews the curriculum integration in school of Architecture with Engineering. The lessons learned from the process will be discussed.
Draft Genome Sequence of the Novel Exopolysaccharide-Producing Bacterium
Altibacter lentus
Strain JLT2010
T
, Isolated from Deep Seawater of the South China Sea
Authors: Zhang Zilian , Chen Yi , Fu Yingnan , Jiao Nianzhi 
Published: October 2014

ABSTRACT

Altibacter lentus
strain JLT2010
T
is the type strain of the recently identified novel genus and species of the family
Flavobacteriaceae
and was first isolated from deep seawater of the South China Sea. It can produce exopolysaccharide. Here we report the first draft genome of JLT2010
T
(3,160,033 bp, with GC content of 42.12%) and major findings from its annotation. It is the first reported genome in the genus
Altibacter
.
First Complete Genome Sequence of a Lineage III Peste des Petits Ruminants Virus
Authors: Dundon William G. , Kihu Simon M. , Settypalli T. Bharani K. , Gitao George C. , Bebora Lily C. , John Njenga M. , Oyugi Julius O. , Silber Roland , Loitsch Angelika , Diallo Adama 
Published: October 2014

ABSTRACT
We report the first complete genome sequence of a lineage III peste des petits ruminants virus (KN5/2011) using RNA extracted from goat lung tissue collected in Kenya in 2011. The genome shows the highest nucleotide sequence identity with lineage II peste des petits ruminants viruses (PPRVs) (86.1 to 87.2%) and the lowest with lineage IV PPRVs (82.5 to 83.8%).
Genome Sequences of Brucella abortus and Brucella suis Strains Isolated from Bovine in Zimbabwe
Authors: Ledwaba Betty , Mafofo Joseph , van Heerden Henriette 
Published: October 2014

ABSTRACT

This is a report of whole-genome sequences of a
Brucella abortus
strain and two
Brucella suis
strains isolated from bovine in Zimbabwe. These strains were selected based on their origin and data obtained when using multiplex PCR assays, then sequenced using next-generation sequencing technologies.
Complete Genome Assembly of
Corynebacterium
sp. Strain ATCC 6931
Authors: Daligault H. E. , Davenport K. W. , Minogue T. D. , Bishop-Lilly K. A. , Bruce D. C. , Chain P. S. , Coyne S. R. , Frey K. G. , Jaissle J. , Koroleva G. I. , Ladner J. T. , Li P-E. , Meincke L. , Munk A. C. , Palacios G. F. , Redden C. L. , Johnson S. L. 
Published: October 2014

ABSTRACT

The genus
Corynebacterium
is best known for the pathogen
C. diphtheriae
; however, it contains mostly commensal and nonpathogenic, as well as several opportunistic, pathogens. Here, we present the 2.47-Mb scaffolded assembly of the type strain,
Corynebacterium
sp
.
ATCC 6931 (NCTC 1914), as deposited into GenBank under accession number CP008913.
Complete Genome Sequences of Two Middelburg Viruses Isolated from Arthropods in the Central African Republic
Authors: Tricou Vianney , Berthet Nicolas , Descorps-Declere Stéphane , Nakouné Emmanuel , Kazanji Mirdad 
Published: October 2014

ABSTRACT
Arboviral diseases are a major threat to human and animal health today. Analysis of whole-genome sequences of decades-old arboviral strains may bring new insights into the viral evolution that might have facilitated outbreaks. Here, we report the whole-genome sequences of two Middelburg viruses isolated several decades ago in the Central African Republic.
Effect of Exercise on Insulin Sensitivity in Healthy Postmenopausal Women: The SHAPE Study
Authors: van Gemert Willemijn A. , Monninkhof Evelyn M. , May Anne M. , Peeters Petra H. , Schuit Albertine J. 
Published: October 2014

Abstract
Background: An inactive lifestyle is a risk factor for several types of cancer. A proposed pathway through which exercise influences cancer risk is via insulin. We aim to investigate the effect of a one-year exercise intervention on insulin sensitivity, and the role of body fat in this association, in healthy, normal to overweight/obese, postmenopausal women.
Methods: In the Sex Hormones And Physical Exercise (SHAPE) study, 189 healthy, inactive and postmenopausal women [ages, 50–69 years; body mass index (BMI), 22–40 kg/m2] were randomly assigned to a one-year aerobic and strength exercise intervention (150 min/wk), or a control group. Between-group differences in fasting insulin, glucose, and homeostatic model assessment of insulin resistance (HOMA2) over time were estimated using linear mixed models.
Results: Follow-up measurements of insulin sensitivity were available for 181 (95.8%) and 182 (96.3%) women at 4 and 12 months, respectively. The intention-to-treat analysis showed no significant differences between the two study groups [treatment effect ratio of the exercise group vs. control (β; 95% confidence interval): insulin, β, 1.07 (0.96–1.19); glucose, β, 1.01 (0.99–1.02); and HOMA2, β, 1.07 (0.96–1.20)]. Similar results were found in a per protocol analysis in compliant women, and in a subgroup of women who lost &gt;2% body fat [measured by dual-energy X-ray absorptiometry (DEXA)].
Conclusions: Participation in a one-year aerobic and strength exercise intervention program did not result in changes in insulin sensitivity in healthy postmenopausal and inactive women.
Impact: Our findings suggest that 150 min/wk of exercise, as recommended by current guidelines, is not enough to achieve improvements in insulin sensitivity and subsequent cancer risk, in healthy postmenopausal women. Cancer Epidemiol Biomarkers Prev; 24(1); 81–87. ©2014 AACR.