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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 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1992

First results from analysis of coordinated AVIRIS, TIMS, and ISM (French) data for the Ronda (Spain) and Beni Bousera (Morocco) peridotites

Ultramafic rocks are relatively rare at the Earth's surface but constitute the vast majority of the Earth by volume. Exposures of ultramafic bodies are therefore crucial for deducing many important processes that occur in the Earth's mantle. An important science question regarding the spatial distribution, abundance, and composition of mafic minerals in ultramafic bodies that can be examined with advanced sensor data is the melting process. When a lherzolite melts, clinopyroxene (cpx) melts first and therefore variations in the modal amount of cpx remaining in the mantle are a reflection of the amount of fractional melting that has occurred. Fe goes preferentially into the melt during melting but a 20 percent batch melting (i.e. closed system) acquires less Fe relative to 20 percent fractional melting (i.e. open system). Since the strength and wavelength of diagnostic absorptions is a strong function of Fe content, it is possible to make maps of the variation in Fe:Mg ratios which can be related to the general melting process. Accurate ground-truth information about local mineralogy provides internal calibration and consistency checks. Investigations using imaging spectrometer are very complementary to field studies because advanced sensor data can provide a synoptic view of modal mineralogy and chemical composition whereas field studies focus on detailed characterization of local areas. Two excellent exposures of ultramafic lithologies are being investigated with visible to mid-infrared imaging spectrometer data: the Ronda peridotite near Ronda, Spain and the Beni Bousera ophiolitic fragment in northern Morocco. Although separated by the Alboran Sea, these bodies are thought to be related and represent fertile sub-continental mantle. The Ronda peridotite is predominantly spinel lherzolite but grades into harzburgite and shows considerable variation in major and trace element compositions. Mafic layering and dykes (i.e. olivine gabbro) are also observed. This indicates some sections of the peridotite have experienced greater degrees of partial melting. The Beni Bousera peridotite also contains mafic layers and dykes and grades into harzburgite representing similar fundamental shifts in the bulk chemistry of this ultramafic body probably related to an episode of partial melting. The specific mode of emplacement of these bodies is controversial and important for understanding the tectonic evolution of this region. Our investigations are not necessarily designed to help resolve this controversy. Rather, these exposures provide excellent and unusual examples of fertile mantle which have undergone variable degrees of partial melting.

Mustard, J. F.↗
NASA NTRS2019

A Satellite Assessment of the Urban Heat Island in Morocco

Urban ecosystems interact with surroundings via land cover changes and their subsequent impact on surface temperature. In emerging countries, large urban agglomerations often form around cities, and only few studies have evaluated their impact. This study carries out the first ever large-scale assessment of urban heat island (UHI) and reflects on its mitigation in Morocco.The analysis reveals a well-defined UHI in urban-areas built within vegetated lands and an urban heat sink (UHS) in urban-areas built within arid regions. Both UHI and UHS amplitudes are higher during day than nighttime, emphasizing vegetation physiological activity. We show a monotonic increase in UHI amplitude with urban-area size. However, unlike previous studies, our analysis shows that as urban-areas built in desert-like environments grow in size, the UHS gradually decreases to ultimately turn into an UHI. On average, cities built within vegetation are warmer than rural fringe by 1.51°C during daytime. This suggests that daytime urban heating may exacerbate the potential climate warming. Our results also suggest that adapted trees constitute a natural cooling mechanism and should be part of urban heating mitigation in Morocco.

Urban Heat Sink↗
NASA NTRSDate not supplied

Tarda an Unusual Carbonaceous Chondrite Meteorite Fall from Morocco

A fireball with a SW to NE trajectory was widely witnessed from the towns of Alnif, Zagora, Tazarine, and Rich in southern Morocco on the 25th of August 2020, around 2:30 pm Moroccan time (GMT+1). The fall was followed immediately by a search campaign by hundreds of Moroccan hunters and curious people in the area of the likely fall zone. On the following day, the first piece was found close to the village of Tarda between Goulmima and Errachidia. A field mission was conducted, and several eyewitnesses were interviewed. They describe a yellow and bright, barrel-sized fireball with green edges lasting ~3s, and accompanied by a whistling sound, followed by multiple detonations. The meteor produced a thick trail of white smoke that remained suspended for several minutes. The fireball was reported to release little pieces around its edges [1].

H. Chennaoui Aoudjehane↗
DOE OSTI2020

Considerations for Medium-Term Load Forecasting in Morocco

There are many factors that determine how demand for electricity may change over time. Medium-term load forecasting is a subset of load forecasting that focuses on the next year. This presentation summarizes analysis performed by NREL on medium-term load forecasting performed for the Moroccan energy system. This analysis includes hourly regressions and load clustering. This work also describes potential next steps that can be implemented by ONEE to improve this medium-term load forecasting.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS2016

Modeling the Urban Impact on Semiarid Surface Climate: A Case Study in Marrakech, Morocco

We combine Landsat and MODIS data in the Simple Biosphere Model to assess the impact of urbanization on surface climate in a semiarid city in North Africa. The model simulates highest temperatures in urban class, with spring average maximum temperature differences to other land cover classes ranging between 1.6 C and 6.0 C. During summer, these maximum temperature differences are smallest (0.5 C) with barelands and highest (8.3 C) with irrigated lawns. This excess heating is simulated above and beyond a seasonal temperature average of about 30 C during spring and 44 C during summer. On annual mean, a full urbanization scenario decreases the carbon fixation by 0.13 MtC and increases the daytime mean surface temperature by 1.3 C. This may boost the city energy consumption by 5.72%. Under a 'smart growth' scenario, whereby the city expands on barelands to cover 50% of the study region and all remaining barelands converted to orchards, the carbon fixation is enhanced by 0.04 MtC with a small daytime temperature increase of 0.2 C. Our results indicate that vegetation can mitigate the urban heating. The hydrological cycle indicates that highest ratio of surface runoff to precipitation (43.8%) occurs in urban areas, versus only 16.7 % for all cover types combined.

Lachir, Asia↗
NASA NTRS2022

Towards Effective Drought Monitoring in the Middle East and North Africa (Mena) Region: Implications From Assimilating Leaf Area Index and Soil Moisture Into the Noah-Mp Land Surface Model for Morocco

The Middle East and North Africa (MENA) region has experienced more frequent and severe drought events in recent decades, leading to increasingly pressing concerns over already strained food and water security. An effective drought monitoring and early warning system is thus critical to support risk mitigation and management by countries in the region. Here we investigate the potential for assimilation of leaf area index (LAI) and soil moisture observations to improve the representation of the overall hydrological and carbon cycles and drought by an advanced land surface model. The results reveal that assimilating soil moisture does not meaningfully improve model representation of the hydrological and biospheric processes for this region, but instead it degrades the simulation of the interannual variation in evapotranspiration (ET) and carbon fluxes, mainly due to model weaknesses in representing prognostic phenology. However, assimilating LAI leads to greater improvement, especially for transpiration and carbon fluxes, by constraining the timing of simulated vegetation growth response to evolving climate conditions. LAI assimilation also helps to correct for the erroneous interaction between the prognostic phenology and irrigation during summertime, effectively reducing a large positive bias in ET and carbon fluxes. Independently assimilating LAI or soil moisture alters the categorization of drought, with the differences being greater for more severe drought categories. We highlight the vegetation representation in response to changing land use and hydroclimate as one of the key processes to be captured for building a successful drought early warning system for the MENA region.

Wanshu Nie↗
DOE OSTI2020

Considerations for Short-Term Load Forecasting of Morocco

There are many factors that determine how demand for electricity may change over time. The analysis described in this report is focused on using auto-regressive models and neural networks to examine load-forecasting techniques for the next 24 hours.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

A techno-economic evaluation of solar-powered green hydrogen production for sustainable energy consumption in Belgium

Here this study focuses on the production and consumption of solar-powered green hydrogen in Belgium by comparing the costs of domestic production with those of imports from Morocco and Namibia. The levelized cost of hydrogen (LCOH) is determined via a techno-economic assessment considering various parameters including, power connectivity, electrolyzer types, location factors, and risk premium. The results show that the lowest LCOH can be achieved by on-grid Proton exchange membrane electrolyzers (PEMEL). LCOH of production in Belgium, Morocco, and Namibia with a PEMEL on-grid system are 5.64, 6.32 and 5.13 euro/kg H 2 , respectively. Thus, importing hydrogen from Namibia to Belgium is more competitive than domestic production. The sensitivity analysis suggests that a target LCOH of 3 euro/kg H 2 is achievable by importing from Namibia through various cost combinations. One of these combinations involves reducing the cost of PV panels to 222.3 euro/kW (70% reduction) and electrolyzers to 363.3 euro/kW (25% reduction).

08 HYDROGEN↗
DOE OSTI2019

Atmospheric Transmittance Model Validation for CSP Tower Plants

In yield analysis and plant design of concentrated solar power (CSP) tower plants, increased uncertainties are caused by the mostly unknown solar attenuation between the concentrating heliostat field and the receiver on top of the tower. This attenuation is caused mainly by aerosol particles and water vapor. Various on-site measurement methods of atmospheric extinction in solar tower plants have been developed during recent years, but during resource assessment for distinct tower plant projects in-situ measurement data sets are typically not available. To overcome this lack of information, a transmittance model (TM) has been previously developed and enhanced by the authors to derive the atmospheric transmittance between a heliostat and receiver on the basis of common direct normal irradiance (DNI), temperature, relative humidity and barometric pressure measurements. Previously the model was only tested at one site. In this manuscript, the enhanced TM is validated for three sites (CIEMAT’s Plataforma Solar de Almería (PSA), Spain, Missour, Morocco (MIS) and Zagora, Morocco (ZAG)). As the strongest assumption in the TM is the vertical aerosol particle profile, three different approaches to describe the vertical profile are tested in the TM. One approach assumes a homogeneous aerosol profile up to 1 kilometer above ground, the second approach is based on LIVAS profiles obtained from Lidar measurements and the third approach uses boundary layer height (BLH) data of the European Centre for Medium-Range Weather Forecasts (ECMWF). The derived broadband transmittance for a slant range of 1 km (T 1$km$ ) time series is compared with a reference data set of on-site absorption- and broadband corrected T 1$km$ derived from meteorological optical range (MOR) measurements for the temporal period between January 2015 and November 2017. The absolute mean bias error (MBE) for the TM’s T 1$km$ using the three different aerosol profiles lies below 5% except for ZAG and one profile assumption. The MBE is close to 0 for PSA and MIS assuming a homogeneous extinction coefficient up to 1 km above ground. The root mean square error (RMSE) is around 5–6% for PSA and ZAG and around 7–8% for MIS. The TM performs better during summer months, during which more data points have been evaluated. This validation proves the applicability of the transmittance model for resource assessment at various sites. It enables the identification of a clear site with high T 1$km$ with a high accuracy and provides an estimation of the T 1$km$ for hazy sites. Thus it facilitates the decision if on-site extinction measurements are necessary. The model can be used to improve the accuracy of yield analysis of tower plants and allows the site adapted design.

14 SOLAR ENERGY↗
DOE OSTI2018

Recovery of Chromium(III) from Tannery Wastewater by Nanoparticles and Whiskers of Chitosan

Chitosan, its nanoparticles and whiskers present an excellent capacity to complex chromium ions. However, this phenomenon is influenced by different parameters. In our search, we determined the appropriate range of pH to form chitosan–Cr(III), nanoparticles Cr(III) and whiskers–Cr(III) complex. We studied also the influence of chromium concentration and nature of chitosan-based materials on complexation process. Our main aim is approximate the optimal conditions to remove chromium(III) from tanning bath, recuperated from tannery wastewater of Marrakech in Morocco. However, the results of adsorption kinetic in tannery wastewater revealed that chitosan, its nanoparticles, whiskers and biocomposites are good sorbent of chromium as well, even if the adsorbed quantity is less compared to chromium solution. Although, according to ICP-OES analysis in this real effluent, nanoparticles are the best complexing ligand, after 24 h of contact nanoparticles can remove 70% of chromium from this tannery wastewater.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2014

Sodium doping effect on physicochemical properties of K{sub 1−x}Na{sub x}CaPb{sub 3}(PO{sub 4}){sub 3} (0 ≤ x ≤ 1) for the determination of mercury(II): Application in seawater samples

Highlights: • The apatite, K{sub 1−x}Na{sub x}CaPb{sub 3}(PO{sub 4}){sub 3} (0 ≤ x ≤ 1), was synthesized using reaction solid. • The obtained apatite was used to determine mercury in seawater samples from Morocco. • The effect of doping sodium into apatite on physic-chemical parameters was studied. • The influence of the electrochemical variables was investigated to determine mercury. - Abstract: A new chemically modified electrode was synthesized for the determination of mercury(II) using differential pulse anodic stripping voltammetry (DPASV). The electrode was modified by lacunar apatite K{sub 1−x}Na{sub x}CaPb{sub 3}(PO{sub 4}){sub 3} (0 ≤ x ≤ 1) synthesized using solid reaction. These powders were crystallized in the hexagonal system, space group P6{sub 3}/m. The effect of sodium content on structural, thermodynamic and electrochemical properties of prepared apatite has been studied. Therefore, the best results was obtained using NaCaPb{sub 3}(PO{sub 4}){sub 3} (x = 1) as modifier of carbon paste electrode for the electrochemical detection of mercury(II). The later ions were preconcentrated on the surface of the modified electrode and oxidized at 0.06 V vs. Ag/AgCl. The electroanalytical procedure comprises of two steps: the chemical accumulation of the analyte under open-circuit conditions followed by the electrochemical detection of the preconcentrated species using differential pulse voltammetry. The different parameters that govern the two steps were optimized. A linear response was obtained in the concentration range from 1.0 mol L{sup −1} × 10{sup −4} mol L{sup −1} to 2.0 mol L{sup −1} × 10{sup −7} mol L{sup −1} Hg(II) after activation of the electrode surface under the optimized conditions. The standard deviation was evaluated in a high and low concentration of mercury(II). The values ​​obtained for seven consecutive measurements were 1.24% and 5.07% of 1.0 mol L{sup −1} × 10{sup −4} mol L{sup −1} and 5.0 mol L{sup −1} × 10{sup −6} mol L{sup −1} mercury(II) solutions respectively. The detection limit and quantification limit for mercury(II), calculated from nine times standard deviation of blank/slope of the calibration graph, were 1.086 mol L{sup −1} × 10{sup −8} mol L{sup −1} and 3.62 mol L{sup −1} × 10{sup −8} mol L{sup −1}, respectively. The proposed chemically modified electrode was applied to determine mercury(II) in seawater samples.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Constructing Memory Through Artistic Practices - 18197

I have been investigating radioactive waste sites internationally since 1994, analyzing how this archaeological stratum of the 21. century can be read in the landscape. Over more than twenty years of work this research has led me to visit several sites around the world. My focus has become the identification of the disposal sites in the landscape, as well as finding ways to pass on memory. Reports on Disposal Sites and Exhibitions: - Dessel, Belgium - exhibition at De Markten, Brussels; - Sacavem, Portugal - participation to the World Exhibition in Lisbon; - El Cabril, Spain - workshop at the University of Bilbao; - Angra dos Reis, Brazil - exhibition at Centre cultural Puc, Rio de Janeiro; - Rokkasho Mura, Japan - exhibition at gallery Gen, Tokyo; - Soulaines D'Huys, France - exhibition at art gallery Cours Carree, Paris; - CSM, Beaumont-Hague, France - exhibition at the House of Culture in Tournai, Belgium; - Fortsmark, Sweden - exhibition at 340 Muzeum, Brussels; - Cnesten Maamora, Morocco - exhibition at Villa des Arts, Casablanca; - Bhabha Atomic Research, Trombay, India - I was allowed to visit it but it was forbidden to make photographs or drawings. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Leveraging concentrating solar power plant dispatchability: A review of the impacts of global market structures and policy

Concentrating solar power (CSP) integrated with thermal energy storage delivers flexible and dispatchable power, which is an increasingly valuable quality as electricity systems integrate growing penetrations of variable renewable energy. Valuing and compensating CSP's dispatchability and flexibility requires electricity market structures and policies that appropriately remunerate generation during high-value portions of the day. In this paper, we review previous analyses of CSP economics and deployment, and we find that continued CSP growth will require valuation mechanisms that appropriately compensate for CSP's flexibility during both plant design and plant operation. We then review market structures that drive CSP operations and dispatch in jurisdictions where CSP is being developed, with perspectives from Spain, Chile, Australia, Morocco, South Africa, the United States, China, and the United Arab Emirates (Dubai). Despite broad agreement that CSP's dispatchability provides value to electricity grids, countries' policies for remunerating and leveraging such dispatchability varies widely. As deployment of CSP and variable renewable energy grows, it will be increasingly important to redesign current integration policies to signal the delivery of CSP's grid services more appropriately.

14 SOLAR ENERGY↗
DOE OSTI2024

Tarda and Tagish Lake: Samples from the same outer Solar System asteroid and implications for D- and P-type asteroids

Here, we report a comprehensive study of the ungrouped type 2 carbonaceous chondrite, Tarda, which fell in Morocco in 2020. This meteorite exhibits substantial similarities to Tagish Lake, Wisconsin Range 91600, and Meteorite Hills 00432, which are generally considered to have originated from a D-type asteroid(s). We constrain the compositions and petrologies of the materials present in a potential sample of a D-type asteroid by reporting the petrography, bulk chemical compositions, bulk H, C, N, Cr, and Ti isotopic compositions, reflectance spectra, and in situ chemical compositions of metals, sulfides, carbonates, and FeO-poor and FeO-rich chondrule silicates of Tarda. We also present new data for Tagish Lake. We then compare Tarda with the other Tagish Lake-like meteorites. Tarda and Tagish Lake appear to be from the same parent body, as demonstrated by their similar petrologies (modal abundances, chondrule sizes), mineral compositions, bulk chemical and isotopic compositions, and reflectance spectra. While the two other Tagish Lake-like meteorites, Wisconsin Range 91600 and Meteorite Hills 00432, show some affinities to Tagish Lake and Tarda, they also share similar characteristics to the Mighei-like carbonaceous (CM) chondrites, warranting further study. Similarities in reflectance spectra suggest that P-type asteroids 65 Cybele and 76 Freia are potential parent bodies of Tarda and the Tagish Lake-like meteorites, or at least have similar surface materials. Since upcoming spacecraft missions will spectrally survey D-type, P-type, and C-type Trojan asteroids (NASA's Lucy) and spectrally study and return samples from Mars' moon Phobos (JAXA's Martian Moons eXploration mission), which is spectrally similar to D-type asteroids, these meteorites are of substantial scientific interest. Furthermore, since Tarda closely spectrally matches P-type asteroids (but compositionally matches the D-type asteroid like Tagish Lake meteorite), P-type and D-type asteroids may represent fragments of the same or similar parent bodies.

58 GEOSCIENCES↗
DOE OSTI2024

Viruses of Nitrogen-Fixing Mesorhizobium Bacteria in Globally Distributed Chickpea Root Nodules

Legume nodules are specialized environments on plant roots that are induced and dominated by nitrogen-fixing bacteria. Bacteriophages (phages) in these nodules could potentially provide top-down controls on the population size and, therefore, the function of nitrogen-fixing symbionts. Here we sought to characterize the diversity and biogeographical patterns of phages that infect nitrogen-fixing Mesorhizobium symbionts isolated from root nodules, leveraging 266 genomes of Mesorhizobium isolated from nodules and 648 nodule metagenomes collected from three species of chickpea plants ( Cicer spp.) under different agricultural management practices, spanning eight countries on five continents. We identified 106 phage populations (viral operational taxonomic units [vOTUs]) in Mesorhizobium draft genomes, 37% of which were confirmed as likely prophages. These vOTUs were detected in 64% of the Mesorhizobium-dominated nodule metagenomes and 58% of the Mesorhizobium isolates. Per metagenome, 1 to 16 putative Mesorhizobium vOTUs were detected, with more than half of the nodules containing only one such vOTU. The majority of vOTUs were detected exclusively in Ethiopia, followed by India and Morocco, with the lowest richness of putative Mesorhizobium phages in countries that applied industrial Mesorhizobium inoculants to crops. Two vOTUs were identified in five or more countries and in nodules dominated by different strains of Mesorhizobium, suggesting infection of diverse Mesorhizobium hosts and long-term interactions. Beta-diversity of these Mesorhizobium phage assemblages was significantly correlated with the dominant Mesorhizobium strain, but not with measured environmental parameters. Our findings indicate that nitrogen-fixing nodules in chickpea plants can contain distinct viral assemblages, with potential impacts on the nodule microbiome that bear further exploration.

Microbiology↗
DOE OSTI2023

Re-Designing the CSP Thermal Energy Storage System to Enable Higher-Temperature Performance at Reduced Cost (Final Technical Report)

Current commercial concentrating solar power (CSP) plants distinguish themselves from ordinary photovoltaic (PV) power plants by storing enough collected energy to enable generation for several hours after the sun goes down. CSP plants store this energy in the sensible heat of nitrate salts in large metallic storage tanks. Stainless-steel AISI 347H (SS347H) is needed for the hot tank operating at about 565 degrees C whereas carbon steel is sufficient for the cold-tank materials. Two-tank nitrate-salt thermal energy storage (TES) is presently in use in several trough-based CSP plants in Europe and in the U.S., operating up to about 390 degrees C. Three commercially operating tower-based CSP plants - Gemasolar in Spain, Crescent Dunes in Nevada, and Noor III in Morocco - use the same approach, storing nitrate salts at temperatures up to 580 degrees C. SS347H is many times more expensive than carbon steel and constitutes a significant cost element in today's CSP plants. Hence, CSP developers need to close the cost gap with PV-based solar plants by making cost reductions in every system of the plant. Redesigning the TES tanks is one opportunity for cost reduction.

14 SOLAR ENERGY↗