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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 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Projections of Environmental Impacts of Biofuels Across Scenarios Using Prospective LCA

This work showcases a collaboration between leading institutions focusing on integrated assessment modeling (IAM) and life cycle assessment (LCA), sponsored - among others - by the International Energy Agency's Technology Collaboration Program on Bioenergy, Task 45. It presents draft results of a prospective LCA for biofuels across world regions, using regional IAM scenario outputs, and life cycle inventories for country-specific pathways.

bioenergy↗
NASA NTRSDate not supplied

Assessing Potential Geophysical and Environmental Impacts from Frequent Rocket Launch Missions at Kennedy Space Center

Kennedy Space Center (KSC) in Florida has been utilized for space missions over many years with a gradually increasing number of rocket launches. There have been multiple studies where air-coupled acoustic waves and infrasound originating from launched rockets were used for operational purposes, such as locating booster trajectories as a function of changing atmospheric conditions. However, no study has utilized the acoustoelastic waves as a signal source for subsurface seismic investigations. We conducted a dispersion analysis using the seismic energy recorded from the Artemis I rocket launch at KSC in November 2022, and from these results we generated depth-sensitivity kernels at different wave frequencies. The kernels were compared with sedimentary core data to verify boundaries of carbonate layers above the Floridan Aquifer System. Accumulative information of bedrock-sediment boundary across the sedimentary platform could especially provide geo-structural evidence that manifests the configuration of coastal features. Continuous dispersion analysis of seismic recordings from consecutive rocket launches also has potential to identify non-stationary environmental effects, such as reorientation of sedimentary structures and fluctuation of the saltwater/groundwater lens from gravitational tides, which may affect erosional susceptibility of coastal features.

Han Byul Woo↗
NASA NTRSDate not supplied

Assessing Potential Geophysical and Environmental Impacts from Frequent Rocket Launch Missions at Kennedy Space Center

Kennedy Space Center (KSC) in Florida has been utilized for space missions over many years with a gradually increasing number of rocket launches. There have been multiple studies where air-coupled acoustic waves and infrasound originating from launched rockets were used for operational purposes, such as locating booster trajectories as a function of changing atmospheric conditions. However, no study has utilized the acoustoelastic waves as a signal source for subsurface seismic investigations. We conducted a dispersion analysis using the seismic energy recorded from the Artemis I rocket launch at KSC in November 2022, and from these results we generated depth-sensitivity kernels at different wave frequencies. The kernels were compared with sedimentary core data to verify boundaries of carbonate layers above the Floridan Aquifer System. Accumulative information of bedrock-sediment boundary across the sedimentary platform could especially provide geo-structural evidence that manifests the configuration of coastal features. Continuous dispersion analysis of seismic recordings from consecutive rocket launches also has potential to identify non-stationary environmental effects, such as reorientation of sedimentary structures and fluctuation of the saltwater/groundwater lens from gravitational tides, which may affect erosional susceptibility of coastal features.

Rocket Launch Seismicity↗
DOE OSTI2024

The environmental impact of hydropower: a systematic review of the ecological effects of sub-daily flow variability on riverine fish

Hydropower can help facilitate power grid decarbonization because it can respond to short-term changes in power demand and is comparatively more reliable than intermittent wind and solar. However, flexible hydropower operations can create rapid and abnormal fluctuations in downstream flow conditions, which can negatively impact aquatic ecosystems. Accordingly, we conducted a systematic review on the ecological effects of hydropower-driven sub-daily flow variability (SDFV) on riverine fishes. We reviewed and synthesized 109 articles relevant to fish-SDFV relationships from seven sources, most of which focused on Salmonids in North America and northern and western Europe and were published in the last 15 years. We found strong agreement in the literature that SDFV increases fish stranding risk, destabilizes habitat, and decreases production and diversity. We found moderate agreement that SDFV interrupts fish reproduction, increases or has no impact on condition, and prompts or discourages movement depending on local channel conditions. We found little to no agreement for relationships between SDFV and mortality, physiology, and behavior. The effects of SDFV on riverine fish ecology are intertwined in the complex suite of biotic and abiotic characteristics that structure aquatic ecosystems and are highly site-, species-, and life stage-specific. Assessments of the impact of SDFV on fish ecology should first characterize local habitat and channel quality and fish community composition to identify specific, measurable ecological outcomes to sustain or enhance, and then design mitigation strategies tailored to those ecological objectives.

13 HYDRO ENERGY↗
DOE OSTI2022

Design of solvent-assisted plastics recycling: Integrated economics and environmental impacts analysis

In 2018, the United States generated over 35. 7 million tons of plastic waste, with only 8.4% being recycled and the other 91.6% incinerated or disposed of in a landfill. The continued growth of the polymer market has raised concerns over the end of life of plastics. Currently, the waste management system is faced with issues of inefficient sorting methods and low-efficiency recycling methods when it comes to plastics recycling. Mechanical recycling is the commonest recycling method but presents a lower-valued recycled material due to the material incompatibilities introduced via the inefficient sorting methods. Chemical recycling offers a promising alternative as it potentially allows for plastics to maintain their original properties. To that end, there is the need to investigate feasible chemical recycling methods to help mitigate the challenging problem posed by plastics at the end-of-life stage. This work proposes a conceptual solvent-assisted plastics recycling framework based on a superstructure optimization approach. This framework is evaluated using a representative case study to recover Polyethylene Terephthalate (PET). In this case study, it is found that polymer recovery is both economically and environmentally favorable when compared to traditional methods of disposal such as incineration.

Lehr, Austin L.↗
DOE OSTI2023

Tailored Bioblendstocks with Low Environmental Impact to Optimize MCCI Engines (Final Technical Report)

The overall objective of the project is to develop and demonstrate a microalgae bio-blendstock with greater than 60% greenhouse gas reduction potential relative to petroleum diesel, that can reduce sooting propensity, increase cetane number and improve engine thermal efficiency relative to a baseline diesel engine operating on conventional fuel. Overall, the project achieved the proposed objectives including producing the final tangible deliverable. A sample of algal bioblendstock was analyzed by National Renewable Energy Laboratory (NREL) staff and partners at Yale University. In addition, the work outlined in this report provides substantial new knowledge on the subjects of algae cultivation, algae conversion to biocrude, biocrude upgrading and combustion optimization.

09 BIOMASS FUELS↗
DOE OSTI2025

Approach to evaluate the effect of selected additives on the environmental impacts of plastic product manufacturing and recycling

Plastic waste management has become a topic of increasing public interest due to the growing amount of plastic waste entering landfills, being combusted, or being leaked into the environment due to mismanagement. The portion of plastic products that is currently recycled remains low (< 9 % in the U.S.). This is driven by numerous factors including infrastructure and collection needs to improve the recycling rate of plastic waste, technological constraints in recycling the wide variety of plastic products associated with the diverse range of (non-transparent) formulations, and economic limitations for recycling plastic and using recycled plastic in new plastic products (e.g., consumer incentives to recycle, economic value of recycled plastic). The relative importance of these factors is not well understood, and each requires additional research.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Long term performance of pilot methanogenic digester filled with seashell wastes treating slaughterhouse wastes: Biogas production and environmental impact

High ammonia and organic acids contents of decomposed slaughterhouse waste (SHW) often result in the severe inhibition or even failure of the anaerobic digestion (AD). The two-stage AD system can alleviate the ammonia inhibition; however, addition of alkali is often needed to maintain the neutral condition. In this study, seashell wastes containing high percentage of calcium carbonate (CaCO 3 ) were for the first time added in a pilot scale methanogenic digester treating chicken blood waste to retain the microorganisms and provide pH buffers for the substrate. A long-duration performance of this digester was conducted for 400 days under different organic loading rates (OLRs). The results show that methane yields of the digester were 244.8 and 224.9 mL g –1 COD added at OLR of 0.4 and 0.6 g COD L –1 d –1 , respectively, higher than the results of previous studies treating the similar feedstock. An AD system treating blood wastes of a typical poultry slaughterhouse was also proposed for which energy balance and carbon footprint analyses were conducted. The energy production of 0.35 MJ kg –1 blood and carbon emissions reduction of 0.05 kg CO 2 -eq kg –1 blood can be achieved from treating blood waste of the broiler chicken. Finally, this study reveals that using seashell wastes in an AD treating SHW can facilitate the reuse of aquaculture wastes and improve the sustainability of meat industry.

09 BIOMASS FUELS↗
DOE OSTI2022

Tracking the environmental impacts of ecological engineering on coastal wetlands with numerical modeling and remote sensing

Coastal wetlands are the most valuable ecosystems on the earth but facing severe degradation and losses owing to climate change and anthropogenic activities. Many ecological engineering projects (EEP) have been conducted to mitigate the degradation of coastal wetlands. However, the geomorphological impacts of EEP on coastal wetlands have not been well documented. In this study, a method employed a process-based hydrodynamic model and remote sensing (RS) was developed to evaluate the impacts of EEP on the geomorphological change of a prototype Ramsar site. Results demonstrated that RS has great potential in improving the quality of bathymetry data for the numerical model with a decrease of RMSE from 0.52 m to 0.3 m. It also showed good capacity in trend detection of geomorphological change spatially. Results showed the Chongming Dongtan wetland experienced erosion with an annual rate of -0.035 m/yr from 2013 to 2016 after the implementation of EEP. The deposition rate changed significantly in the area within 200 m of the EEP. It is found that the EEP modified the composition of vegetation, sediment transportation, as well as substrate stability, affecting the geomorphological change of coastal wetlands. It is suggested that the EEP with moderate anthropogenic disturbance is a direct and effective way to recover the coastal habitats for waterbirds. However, the modification of the coastal wetland ecosystem by EEP will lead to the potential vulnerability to global climate change. Therefore, how to mitigate the advantages and disadvantages of the EEP is needed to be further studied to find a more sustainable way for coastal management.

geomorphological change, coastal wetlands, Ecologi↗