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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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All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

A Community-Based Approach to Developing a Mobile Device for Measuring Ambient Air Exposure, Location, and Respiratory Health

In west Eugene (Oregon), community research indicates residents are disproportionately exposed to industrial air pollution and exhibit increased asthma incidence. In Carroll County (Ohio), recent increases in unconventional natural gas drilling sparked air quality concerns. These community concerns led to the development of a prototype mobile device to measure personal chemical exposure, location, and respiratory function. Working directly with the environmental justice (EJ) communities, the prototype was developed to (1) meet the needs of the community and; (2) evaluate the use in EJ communities. The prototype was evaluated in 3 community focus groups (n=25) to obtain feedback on the prototype and feasibility study design to evaluate the efficacy of the device to address community concerns. Focus groups were recorded and qualitatively analyzed with discrete feedback tabulated for further refinement. The prototype was improved by community feedback resulting in 8 alterations/additions to software and instructional materials. Overall, focus group participants were supportive of the device and believed it would be a useful environmental health tool. The use of focus groups ensured that community members were engaged in the research design and development of a novel environmental health tool. We found that community-based research strategies resulted in a refined device as well as relevant research questions, specific to the EJ community needs and concerns.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

The reference genome for the northeastern Pacific bull kelp, Nereocystis luetkeana

Bull kelp, Nereocystis luetkeana, is a northeastern Pacific kelp with broad distribution from Alaska to central California. Its population declines have caused severe concerns in northern California, the Salish Sea in Washington, and recently in some populations in Oregon. Despite bull kelp's accumulated ecological and physiological studies, an assembled and annotated genomic reference was still unavailable. Here, we report the complete and annotated genome of Nereocystis luetkeana, produced by the California Conservation Genomics Project (CCGP), which aims to reveal genomic diversity patterns across California by sequencing the complete genomes of approximately 150 carefully selected species. The genome was assembled into 1562 scaffolds with 449.82 Mb, 80x of coverage and 22 952 gene models. BUSCO assembly showed a completeness score of 72% for the stramenopiles gene set. The mitochondria and chloroplast genome sequences have 37 Kb and 131 Mb, respectively. The orthology analysis between 10 Phaeophycean genomes showed 1065 expanded and 286 unique orthogroups for this species. Pairwise comparisons showed 542 orthogroups present only in N. luetkeana and M. pyrifera, another large-body kelp. The enrichment analysis of these orthogroups showed important functions related to central metabolism and signaling due to ATPases enrichment in these two species. This genome assembly will provide an essential resource for the ecology, evolution, conservation, and breeding of bull kelp.

California Conservation Genomics Project—CCGP↗
DOE OSTI2016

The View from the Top of the Mountain: Building a Community of Practice with the GridWise Transactive Energy Framework

The topic of “transactive energy” has received growing attention over the past eighteen months. It has been a part, for example, of the NY Reforming the Energy Vision discussions and the topic of activities such as the National Institute of Standards Transactive Energy Challenge. The growing discussion stems from the realization that new approaches are needed to efficiently and reliably integrate growing numbers of distributed energy resources. In anticipation of the applicability of transactive energy systems to emerging challenges in Grid integration, the GridWise® Architecture Council (GWAC) began to build a community of practice in the area of transactive energy systems. Starting with a workshop on the topic of “transactive energy” in May 2011, the Council brought together about a dozen interested researchers and practitioners from utilities, vendors, labs and academia to compare their approaches and experience in order to create common definitions and understanding within this topical area. This was followed in March 2012 with a second workshop during which about twice as many attendees continued the discussion. At this workshop the need for both a roadmap and a document documenting the foundations of transactive energy, common vocabulary and other definitional aspects was recognized. These two workshops led to the Council organizing the First International Conference and Workshop on Transactive Energy which took place May 23 – 24, 2013 in Portland, Oregon. The Council has continued this work with additional topical workshops, the Second International Conference and Workshop on Transactive Energy held in December 2014, and is currently organizing the Third International Conference and Workshop on Transactive Energy Systems to be held in May 2016. This article provides a summary of the Council’s work to build the community of practice through creation of a Transactive Energy Framework document and related activities. In addition to seeing transactive energy discussions on the agenda for many conferences there are also group activities relating to transactive energy being coordinated by both NIST and SGIP with which GWAC is also involved. The NIST work aims to develop and enhance modeling and simulation tools and integration into modeling and simulation platforms for Transactive Energy evaluation, as well as demonstrate how different transactive approaches may be used to improve reliability and efficiency of the electric grid. This will be accomplished through development of a set of scenarios that can serve as ongoing reference points for modeling and simulation. It is also an example of helping to develop a Transactive Energy community. The ongoing Transactive Energy Coordination Group formed by SGIP reviews the progress and directions of transactive energy activities in related parts of the SGIP and collaborating organizations such as GWAC. One of its activities is assembling a core set of transactive energy use cases as representative of the transactive energy interface requirements. This will enable assessment of interoperability requirements for transactive energy applications and an analysis of standards coverage, gaps, and future needs.

Tranasactive Energy↗
DOE OSTI2020

Energy Storage Control Capability Expansion: Achieving Better Technoeconomic Benefits at Portland General Electric's Salem Smart Power Center

This article reports a transformative project aimed at enhancing the control capabilities of a Portland General Electric (PGE) owned 5 MW/1.25 MWh ESS located at Salem Smart Power Center (SSPC), Salem, Oregon, USA toward achieving better techno-economic benefit. Steps for developing a value-driven control capability is illustrated starting from evaluation of economic opportunities that drive the coordination of multiple services to be delivered by an ESS to implementation and testing. Lessons learned during critical processes are identified for the benefit of the ESS industry.

Alam, Md Jan E.↗
DOE OSTI2023

Hydropower Evaluation Framework for Wildfire Resilient Microgrids

This paper presents a framework for characterizing hydropower plants based on plant and site attributes, assessing their feasibility to function within microgrids during periods of wildfire-induced outages. A set of nine metrics is developed to assign scores to hydropower plants, considering their suitability for forming wildfire-resilient microgrids, their capability to operate within such microgrids, and their simulated performance during wildfire events. A comprehensive database is constructed, comparing hydropower plants according to their suitability and capability metrics. To evaluate the performance score of a specific hydropower plant, namely the Hills Creek plant situated in a wildfire-prone region of Oregon, a case study is conducted, simulating a wildfire scenario. The results of steady-state and dynamic simulations demonstrate that the Hills Creek hydropower plant can effectively provide crucial microgrid services and power nearby communities during a prolonged wildfire-related outages.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2018

Assessment of the National Solar Radiation Database (NSRDB 1998-2016)

Applying traceable and standardized uncertainty characterization for solar resource data provides confidence in the dataset for use by financiers, developers and site operators of solar energy conversion systems, and ultimately reduces deployment cost. Performance guarantees of solar energy conversion systems are based on the available solar resource from measurement stations or modeled dataset such as the National Solar Radiation Database (NSRDB). In this study we implemented a comprehensive uncertainty determination approach [1]. The study also analyzed how the NSRDB (19982016) - Version 3 compares with the previous NSRDB (19982015) - Version 2. The study also attempted to estimate the uncertainty differences derived by comparing theNSRDB data to the seven measurement stations from the National Oceanic and Atmospheric Administration's Surface Radiation Budget Network (SURFRAD) and University of Oregon Solar Radiation Monitoring Laboratory (SRML). The evaluation was conducted for hourly values, daily totals, monthly mean daily totals, and annual mean monthly mean daily totals and demonstrate the qualityof the new datasets currently available from the NSRDB.

14 SOLAR ENERGY↗
DOE OSTI2014

Geochemical, metagenomic and metaproteomic insights into trace metal utilization by methane-oxidizing microbial consortia in sulfidic marine sediments

Microbes have obligate requirements for trace metals in metalloenzymes that catalyze important biogeochemical reactions. In anoxic methane- and sulfide-rich environments, microbes may have unique adaptations for metal acquisition and utilization due to decreased bioavailability as a result of metal sulfide precipitation. However, micronutrient cycling is largely unexplored in cold ( 10 C) and sulfidic (>1 mM H2S) deep-sea methane seep ecosystems. We investigated trace metal geochemistry and microbial metal utilization in methane seeps offshore Oregon and California, USA, and report dissolved concentrations of nickel (0.5-270 nM), cobalt (0.5-6 nM), molybdenum (10-5,600 nM) and tungsten (0.3-8 nM) in Hydrate Ridge sediment porewaters. Despite low levels of cobalt and tungsten, metagenomic and metaproteomic data suggest that microbial consortia catalyzing anaerobic oxidation of methane utilize both scarce micronutrients in addition to nickel and molybdenum. Genetic machinery for cobalt-containing vitamin B12 biosynthesis was present in both anaerobic methanotrophic archaea (ANME) and sulfate-reducing bacteria (SRB). Proteins affiliated with the tungsten-containing form of formylmethanofuran dehydrogenase were expressed in ANME from two seep ecosystems, the first evidence for expression of a tungstoenzyme in psychrotolerant microorganisms. Finally, our data suggest that chemical speciation of metals in highly sulfidic porewaters may exert a stronger influence on microbial bioavailability than total concentration

Glass, DR. Jennifer↗
DOE OSTI2016

Modelling individual variability in growth of bull trout in the Walla Walla River Basin using a hierarchical von Bertalanffy growth model

Abstract We examined growth in length of fluvial bull trout ( Salvelinus confluentus ) in the Walla Walla River Basin, Washington and Oregon. Our objectives were to quantify individual variability in growth; examine growth within and among years, life history forms, life stages and sexes; and estimate von Bertalanffy growth parameters. Individual variability was evaluated by modelling asymptotic length ( L ∞ ) and the growth coefficient ( k ) as random variables. All models were fit with Bayesian methods and were evaluated for fit by the deviance information criterion. By incorporating individual variability, population‐level estimates of L ∞ and k appeared appropriate and estimated growth trajectories for specific bull trout fit individual observed patterns in growth. Growth trajectories and positive correlation between individual estimates of L ∞ and k suggest that some individuals grow at a faster rate and reach a larger maximum size than other individuals and those differences are maintained throughout life. Selected models suggest that fluvial migrants have higher estimates of L ∞ and k than residents, but there were only slight differences in parameter estimates among migrants from two adjacent spawning populations in the Walla Walla River Basin, as well as between males and females. Growth rates increased for fluvial migrants after subadult emigration. Individual variability in growth is consistent with the life history diversity assumed essential for bull trout population persistence. Quantifying this variability is important for modelling population dynamics and viability to conserve this threatened species.

Harris, Julianne E.↗
DOE OSTI2017

Changes in native bull trout and non‐native brook trout distributions in the upper Powder River basin after 20 years, relationships to water temperature and implications of climate change

Abstract Many bull trout populations have declined from non‐native brook trout introductions, habitat changes (e.g. water temperature) and other factors. We systematically sampled the distribution of bull trout and brook trout in the upper Powder River basin in Oregon in the 1990s and resampled it in 2013–2015, examined temperature differences in the habitats of the two species and analysed trends in temperatures in the light of possible increases associated with climate change. The species’ distributions are currently similar to those in the 1990s, except in one stream where bull trout declined. However, bull trout consisting of resident forms remain restricted to a few kilometres of habitat at the upper end of fish distribution. In streams where both species occur, the typical pattern was an intermediate zone of mixed bull trout, brook trout, and hybrids downstream of allopatric bull trout and allopatric brook trout extending farther downstream. Temperature differences between where bull trout and most brook trout occurred were small (0.5–1.0°C August mean). There were no statistical increases in water temperatures in nearby streams since the 1990s and no warming trends in air temperatures for the past 25–60 years. However, peak summer water temperatures are occurring about 3 weeks earlier than 25 years ago. Future effects of climate change, including possible increases in temperature, changes in timing and other factors (e.g. snowpack, flow and extreme events) remain a concern for the persistence of these populations. However, it is difficult to precisely predict where those changes will occur and what they will be.

Howell, Philip J.↗
DOE OSTI2015

Metabolic associations with archaea drive shifts in hydrogen isotope fractionation in sulfate‐reducing bacterial lipids in cocultures and methane seeps

Abstract Correlation between hydrogen isotope fractionation in fatty acids and carbon metabolism in pure cultures of bacteria indicates the potential of biomarker D/H analysis as a tool for diagnosing carbon substrate usage in environmental samples. However, most environments, in particular anaerobic habitats, are built from metabolic networks of micro‐organisms rather than a single organism. The effect of these networks on D/H of lipids has not been explored and may complicate the interpretation of these analyses. Syntrophy represents an extreme example of metabolic interdependence. Here, we analyzed the effect of metabolic interactions on the D/H biosignatures of sulfate‐reducing bacteria ( SRB ) using both laboratory maintained cocultures of the methanogen Methanosarcina acetivorans and the SRB Desulfococcus multivorans in addition to environmental samples harboring uncultured syntrophic consortia of anaerobic methane‐oxidizing archaea ( ANME ) and sulfate‐reducing Deltaproteobacteria ( SRB ) recovered from deep‐sea methane seeps. Consistent with previously reported trends, we observed a ~80‰ range in hydrogen isotope fractionation (ε lipid–water ) for D. multivorans grown under different carbon assimilation conditions, with more D‐enriched values associated with heterotrophic growth. In contrast, for cocultures of D. multivorans with M. acetivorans, we observed a reduced range of ε lipid – water values (~36‰) across substrates with shifts of up to 61‰ compared to monocultures. Sediment cores from methane seep settings in Hydrate Ridge (offshore Oregon, USA ) showed similar D‐enrichment in diagnostic SRB fatty acids coinciding with peaks in ANME / SRB consortia concentration suggesting that metabolic associations are connected to the observed shifts in ε lipid–water values.

Dawson, K. S.↗
DOE OSTI2025

Which Plant Traits Increase Soil Carbon Sequestration? Empirical Evidence From a Long‐Term Poplar Genetic Diversity Trial

Plants play a key role in mediating soil response to global change, and breeding or engineering crops to increase soil organic carbon (SOC) storage is a potential route to land-based carbon dioxide removal in agricultural systems. However, due to limited observational datasets plus shifting paradigms of SOC stabilization, it is unclear which plant traits are most important for enhancing different types of soil organic matter. Existing long-term common gardens of genetically diverse plant populations may provide an opportunity to evaluate biological controls on SOC, separate from environmental or management variability. Here we report on soil and root chemical data collected for 24 genotypes within a 13-year-old common garden in northwestern Oregon planted with a large natural variant population of Populus trichocarpa. Fractionating surface soil (0–15 cm) revealed substantial variation in stocks of mineral-associated organic matter (MAOM; 18–67 t C/ha) and particulate organic matter (POM; 2–22 t C/ha). Tree genotype explained 24% and 26% of the MAOM and POM stock variability, respectively, after controlling for background variability. We found minimal association between SOC concentration and either aboveground tree productivity or root biomass recalcitrance (C/N ratios and lignin content). In contrast, root elemental content appeared influential for MAOM-C concentration, which showed a strong positive association with root aluminum (Al) and a strong negative association with root boron (B) and magnesium (Mg). Furthermore, root concentrations of these elements were highly heritable (57%–78%) and not simply a reflection of background variation in soil elemental concentrations. We estimate that surface SOC stocks under these 24 genotypes have diverged at rates of up to 1.2–4.3 t C/ha/year. These results suggest that long-term genetic diversity trials have value for elucidating biological controls on soil organic matter dynamics, and that traits associated with root elemental content may be a useful target for enhancing biosequestration.

biomass recalcitrance↗
DOE OSTI2011

Reduced diurnal temperature range does not change warming impacts on ecosystem carbon balance of Mediterranean grassland mesocosms

Daily minimum temperature (T min ) has increased faster than daily maximum temperature (T max ) in many parts of the world, leading to decreases in diurnal temperature range (DTR). Projections suggest these trends are likely to continue in many regions, particularly northern latitudes and in arid regions. Despite wide speculation that asymmetric warming has different impacts on plant and ecosystem production than equal-night-and-day warming, there has been little direct comparison of these scenarios. Reduced DTR has also been widely misinterpreted as a result of night-only warming, when in fact T min occurs near dawn, indicating higher morning as well as night temperatures. We report on the first experiment to examine ecosystem-scale impacts of faster increases in T min than T max , using precise temperature controls to create realistic diurnal temperature profiles with gradual day-night temperature transitions and elevated early morning as well as night temperatures. Studying a constructed grassland ecosystem containing species native to Oregon, USA, we found the ecosystem lost more carbon at elevated than ambient temperatures, but was unaffected by the 3ºC difference in DTR between symmetric warming (constantly ambient +3.5ºC) and asymmetric warming (dawn T min =ambient +5ºC, afternoon T max = ambient +2ºC). Reducing DTR had no apparent effect on photosynthesis, likely because temperatures were most different in the morning and late afternoon when light was low. Respiration was also similar in both warming treatments, because respiration temperature sensitivity was not sufficient to respond to the limited temperature differences between asymmetric and symmetric warming. We concluded that changes in daily mean temperatures, rather than changes in T min /T max , were sufficient for predicting ecosystem carbon fluxes in this reconstructed Mediterranean grassland system.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

The Algae Foundation® and Algae Technology Educational Consortium

Abstract The Algae Foundation established in February 2013 has developed a diverse portfolio of algal‐based education and workforce development programs covering education levels from kindergarten through college, aquaculture extension, and free online courses. The Algae Foundation created the Algae Technology Educational Consortium (ATEC) with five major foci including community college certificate program in algae cultivation; community college curriculum adopted for algal biotechnology degree programs; Algal Massive Open Online Courses (Algal MOOCs); Algae Academy, a kindergarten to 12th grade STEM curriculum initiative; and aquaculture extension education through the Algae Cultivation Extension Short courses (ACES). The results include the education and training of over 102,000 students, aquaculturists, entrepreneurs, and bioeconomy‐based professionals aged 8–75 years in all 50 U.S. states and 66 countries. ATEC has completed agreements with 21 community colleges and universities located in Arizona, California, Connecticut, Hawaii, Louisiana, Maine, New Mexico, North Carolina, Oregon, Texas, and Washington. The first ATEC‐sponsored certificate degree program graduation was in May 2018. The Algae MOOC #1 has had over 15,752 students enrolled. ATEC initiated the Algae Academy in spring 2016 in Carlsbad, CA, and expanded to serving over 34,000 students in 46 states during the academic year 2019–2020. ACES has enrolled over 1,550 students from 66 countries.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2022

Riparian vegetation shade restoration and loss effects on recent and future stream temperatures

River temperatures are expected to increase this century harming species requiring cold-water habitat unless restoration activities protect or improve habitat availability. Local shading by riparian vegetation can cool water temperatures, but uncertainty exists over the scaling of this local effect to larger spatial extents. Here, we evaluate this issue using a regional spatial stream network temperature model with covariates representing shade effects to predict mean August stream temperatures across 78,195 km of tributaries flowing into the Columbia River in the northwestern United States. We evaluate nine scenarios predicting stream temperatures for three riparian shade conditions (current, restored, and no riparian vegetation) within three different climate periods (2000s, 2040s, and 2080s). Results suggest riparian shade restoration (2000s climate) could decrease mean August stream temperatures by 0.62°C across the study network. Under the same restored shade conditions, temperature predictions for tributaries at their confluence with the Columbia River range from 0.02 to 2.08°C cooler than under current shade conditions. The climate warming effect predicted for the 2040s and 2080s, however, is greater than the cooling effect from restoring riparian shade. Streams less than 10-m bankfull width cooled more frequently with riparian shade restoration. In Oregon, the proportion of fish habitat for salmon and trout rearing and migration that meet temperature numeric water quality criteria could be increased by 20% under restored shade conditions although net habitat declines may still occur in the future. We conclude riparian vegetation restoration could partially mitigate future warming and help maintain cold-water habitats that function as thermal refuges if implemented strategically.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Disturbance: a double-edged sword for restoration in a changing climate

Ecological restoration often relies on disturbance as a tool for establishing target plant communities, but disturbance can be a double-edged sword, at times initiating invasion and unintended outcomes. Here, in this study, we test how fire disturbance, designed to enhance restoration seeding success, combines with climate and initial vegetation conditions to shift perennial versus annual grass dominance and overall community diversity in Pacific Northwest grasslands. We seeded both native and introduced perennial grasses and native forbs in paired, replicated burned-unburned plots in three sites along a latitudinal climate gradient from southern Oregon to central-western Washington. Past restoration and climate manipulations at each site had increased the variation of starting conditions between plots. Burning promoted the expansion of extant forbs and perennial grasses across all sites. Burning also enhanced the seeding success of native perennial grass and native forbs at the northern and central site, and the success of introduced perennial grasses across all three sites. Annual grass dominance was driven more by latitude than burning, with annuals maintaining their dominance in the south and perennials in the north. At the same time, unrestored grasslands surrounding all sites remained dominated by perennial grasses, suggesting that initial plot clearing may have allowed for annual grass invasion in the southern site. When paired with disturbance, further warming may increase the risk of annual grass dominance, a potentially persistent state.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

An Efficient Three-Dimensional CFD-Based Numerical Wave Tank for a Wave Energy Converter in Extreme Irregular Waves

A numerical wave tank approach for computational fluid dynamics (CFD) modelling of an extreme irregular seastate is presented. The technique couples a potential flow solution with a CFD solver for more efficient numerical predictions. This method has recently become attractive both for the research community and the industry working with offshore structures. The model is used to determine the response of a submerged pressure differential wave energy converter (WEC) in a fully nonlinear irregular wave condition using the high-fidelity CFD code, STAR-CCM+. Potential flow based numerical models are commonly used to predict motions and performance of wave energy converters. Wave kinematics can deviate from potential flow predictions for extreme wave conditions; the excitation loads on an absorber can also be increasingly influenced by viscous effects, not predicted by potential flow engineering level models. In these extreme conditions, a Reynolds-averaged Navier-Stokes CFD model can better predict motions and loads for a WEC. Long time series with varying random seed numbers can be used to identify singular extreme wave events from a stochastic irregular sea state. This approach simulates a more realistic wave series for a given sea state than a regular wave or a focused wave. However, it is computationally infeasible to run these long time series for three-dimensional (3D) CFD simulations. In this work, two-dimensional (2D) CFD simulations with a long domain allow the full development of an extreme nonlinear wave condition. The results are used to identify extreme events from a 50-year storm condition for the PacWave site off the coast of Oregon. A relatively short time window including this extreme event is then mapped to a 3D simulation using a user defined wave methodology. Convergence studies for domain length, wave forcing lengths, and time before the extreme event were conducted.

CFD↗
DOE OSTI2013

Turing instability in reaction-diffusion systems with nonlinear diffusion

The Turing instability is studied in two-component reaction-diffusion systems with nonlinear diffusion terms, and the regions in parametric space where Turing patterns can form are determined. The boundaries between super- and subcritical bifurcations are found. Calculations are performed for one-dimensional brusselator and oregonator models.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗