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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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New technology concepts and structural analysis development needs which could lead to improved life cycle cost for future high-bypass turbofans were studied. The NASA-GE energy efficient engine technology is used as a base to assess the concept benefits. Recommended programs are identified for attaining these generic structural and other beneficial technologies.
An added challenge for the designers of large scale systems such as Space Station Freedom is the appropriate incorporation of intelligent system technology (artificial intelligence, expert systems, knowledge-based systems, etc.) into their requirements and design. This presentation will describe a view of systems engineering which successfully addresses several aspects of this complex problem: design of large scale systems, design with requirements that are so complex they only completely unfold during the development of a baseline system and even then continue to evolve throughout the system's life cycle, design that involves the incorporation of new technologies, and design and development that takes place with many players in a distributed manner yet can be easily integrated to meet a single view of the requirements. The first generation of this methodology was developed and evolved jointly by ISX and the Lockheed Aeronautical Systems Company over the past five years on the Defense Advanced Research Projects Agency/Air Force Pilot's Associate Program, one of the largest, most complex, and most successful intelligent systems constructed to date. As the methodology has evolved it has also been applied successfully to a number of other projects. Some of the lessons learned from this experience may be applicable to Freedom.
Air transport is a continually expanding industry, a fact that has become even more evident with the recovery of the aviation industry post-COVID-19. This expansion amplified energy consumption at airports, which was already significantly high. Airport decision-makers are increasingly focusing on improving sustainability and addressing social, economic, and environmental criteria across airports worldwide. In this article, we propose a decision-making model for identifying a sustainable airport technology solution that minimizes the energy consumption of airport lighting while considering economic, emission, and life-cycle criteria. The proposed model combines data envelopment analysis and multi-criteria decision making techniques. We applied the model to the Dallas/Fort Worth International Airport (DFW) as a case study, considering eight lighting technology solutions, each with five luminous flux alternatives. Our model identified the best lighting technology solution for DFW outdoor and indoor environments based on the following criteria: luminous flux, capital costs, life-cycle costs, energy consumption, and emissions (CO2e, NOx, SO2, and PM2.5). The designed model is customizable to any airport and is applicable to a wide range of airport lighting technologies. In our analysis, Light-Emitting Diode lighting emerged as the most sustainable technology option. It ranked first in most cases due to its balance of high efficacy, long lifespan, low life-cycle cost, low capital cost, and lower emissions across all pollutants.
To fully evaluate energy and emission impacts of advanced vehicle technologies and new transportation fuels, the fuel cycle from wells to wheels and the vehicle cycle through material recovery and vehicle disposal need to be considered. Sponsored by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE), Argonne has developed a full life-cycle model called GREET (Greenhouse gases, Regulated Emissions, and Energy use in Technologies). It allows researchers and analysts to evaluate various vehicle and fuel combinations on a full fuel-cycle/vehicle-cycle basis. The first version of GREET was released in 1996. Since then, Argonne has continued to update and expand the model. GREET is developed as a multidimensional spreadsheet model in Microsoft Excel. It provides a comprehensive, life-cycle-based approach to compare the energy use and emissions of conventional and advanced vehicle technologies. It includes two sub-models named Fuel-Cycle Model (GREET 1, contains data on fuel cycles and vehicle operations) and Vehicle-Cycle Model (GREET 2, evaluates the energy and emission effects associated with vehicle material recovery and production, vehicle component fabrication, vehicle assembly, and vehicle disposal/recycling). This public domain model is available free of charge for anyone to use.
To fully evaluate energy and emission impacts of advanced vehicle technologies and new transportation fuels, the fuel cycle from wells to wheels and the vehicle cycle through material recovery and vehicle disposal need to be considered. Sponsored by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE), Argonne has developed a full life-cycle model called GREET (Greenhouse gases, Regulated Emissions, and Energy use in Technologies). It allows researchers and analysts to evaluate various vehicle and fuel combinations on a full fuel-cycle/vehicle-cycle basis. The first version of GREET was released in 1996. Since then, Argonne has continued to update and expand the model. GREET is developed as a multidimensional spreadsheet model in Microsoft Excel. It provides a comprehensive, life-cycle-based approach to compare the energy use and emissions of conventional and advanced vehicle technologies. It includes two sub-models named Fuel-Cycle Model (GREET 1, contains data on fuel cycles and vehicle operations) and Vehicle-Cycle Model (GREET 2, evaluates the energy and emission effects associated with vehicle material recovery and production, vehicle component fabrication, vehicle assembly, and vehicle disposal/recycling). This public domain model is available free of charge for anyone to use.
To fully evaluate energy and emission impacts of advanced vehicle technologies and new transportation fuels, the fuel cycle from wells to wheels and the vehicle cycle through material recovery and vehicle disposal need to be considered. Sponsored by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE), Argonne has developed a full life-cycle model called GREET (Greenhouse gases, Regulated Emissions, and Energy use in Technologies). It allows researchers and analysts to evaluate various vehicle and fuel combinations on a full fuel-cycle/vehicle-cycle basis. The first version of GREET was released in 1996. Since then, Argonne has continued to update and expand the model. GREET is developed as a multidimensional spreadsheet model in Microsoft Excel. It provides a comprehensive, life-cycle-based approach to compare the energy use and emissions of conventional and advanced vehicle technologies. It includes two sub-models named Fuel-Cycle Model (GREET 1, contains data on fuel cycles and vehicle operations) and Vehicle-Cycle Model (GREET 2, evaluates the energy and emission effects associated with vehicle material recovery and production, vehicle component fabrication, vehicle assembly, and vehicle disposal/recycling). This public domain model is available free of charge for anyone to use.
To fully evaluate energy and emission impacts of advanced vehicle technologies and new transportation fuels, the fuel cycle from wells to wheels and the vehicle cycle through material recovery and vehicle disposal need to be considered. Sponsored by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE), Argonne has developed a full life-cycle model called GREET (Greenhouse gases, Regulated Emissions, and Energy use in Technologies). It allows researchers and analysts to evaluate various vehicle and fuel combinations on a full fuel-cycle/vehicle-cycle basis. The first version of GREET was released in 1996. Since then, Argonne has continued to update and expand the model. GREET is developed as a multidimensional spreadsheet model in Microsoft Excel. It provides a comprehensive, life-cycle-based approach to compare the energy use and emissions of conventional and advanced vehicle technologies. It includes two sub-models named Fuel-Cycle Model (GREET 1, contains data on fuel cycles and vehicle operations) and Vehicle-Cycle Model (GREET 2, evaluates the energy and emission effects associated with vehicle material recovery and production, vehicle component fabrication, vehicle assembly, and vehicle disposal/recycling). This public domain model is available free of charge for anyone to use.
Cost/benefit analyses to evaluate advanced material technologies projects considered for general aviation and turboprop commuter aircraft through estimated life-cycle costs, direct operating costs, and development costs are discussed. Specifically addressed is the selection of technologies to be evaluated; development of property goals; assessment of candidate technologies on typical engines and aircraft; sensitivity analysis of the changes in property goals on performance and economics, cost, and risk analysis for each technology; and ranking of each technology by relative value. The cost/benefit analysis was applied to a domestic, nonrevenue producing, business-type jet aircraft configured with two TFE731-3 turbofan engines, and to a domestic, nonrevenue producing, business type turboprop aircraft configured with two TPE331-10 turboprop engines. In addition, a cost/benefit analysis was applied to a commercial turboprop aircraft configured with a growth version of the TPE331-10.
This paper reviewed the entire life cycle of plastics and options for the management of plastic waste to address barriers to industrial chemical recycling and further provide perceptions on possible opportunities with such materials.
The raw data and figures used in Davis et al. (2025), "A Comparative Analysis of Waste-as-a-Feedstock Accounting Methods in Life Cycle Assessments," published in MDPI Hydrogen journal.
This study presents the results of a preliminary assessment on the technology, economics, and sustainability of using waste plastics as a feedstock to produce low molecular weight olefins via pyrolysis and gasification pathways. We also studied the formation of formaldehyde - an important polymer precursor - via the gasification of waste plastics. Process pathways for recovery of ethylene and propylene and production of formaldehyde from a simulated mixed plastic waste were constructed based on literature data. They included direct and indirect pathways based on either gasification or pyrolysis as the primary conversion step. Results of these studies have shown that significant economic challenges exist of producing olefins via pyrolysis and gasification, with the latter pathway especially difficult. Base costs of pyrolysis naphtha from waste plastics are higher when compared to the same material produced from fossil feedstocks. Base olefin costs for one direct route are two times higher than comparable costs from steam cracking of fossil naphtha. These costs are driven primarily by feedstock costs; some pyrolysis scenarios become more economically feasible when very low feedstock costs are used. Similarly, for gasification, the cost of methanol - the central intermediate - was found to be noticeable higher when produced by gasification of waste plastics compared to current selling prices, which negatively impacts all pathways that go through methanol as the central intermediate. Life-cycle assessment indicates that the production of pyrolysis naphtha from plastics is a carbon intensive operation; no major advantages were found in terms of greenhouse gas emissions for any of the pathways producing C2 and C3 olefins. The results of this study can serve as the baseline for future comparison to other plastic waste valorization processes.
Individual pressure vessel (IPV) nickel-hydrogen technology was advanced at NASA Lewis and under Lewis contracts with the intention of improving cycle life and performance. One advancement was to use 26 percent potassium hydroxide (KOH) electrolyte to improve cycle life. Another advancement was to modify the state-of-the-art cell design to eliminate identified failure modes. The modified design is referred to as the advanced design. A breakthrough in the low-earth-orbit (LEO) cycle life of IPV nickel-hydrogen cells has been previously reported. The cycle life of boiler plate cells containing 26 percent KOH electrolyte was about 40,000 LEO cycles compared to 3,500 cycles for cells containing 31 percent KOH. The boiler plate test results are in the process of being validated using flight hardware and real time LEO testing at the Naval Weapons Support Center (NWSC), Crane, Indiana under a NASA Lewis Contract. An advanced 125 Ah IPV nickel-hydrogen cell was designed. The primary function of the advanced cell is to store and deliver energy for long-term, LEO spacecraft missions. The new features of this design are: (1) use of 26 percent rather than 31 percent KOH electrolyte; (2) use of a patented catalyzed wall wick; (3) use of serrated-edge separators to facilitate gaseous oxygen and hydrogen flow within the cell, while still maintaining physical contact with the wall wick for electrolyte management; and (4) use of a floating rather than a fixed stack (state-of-the-art) to accommodate nickel electrode expansion due to charge/discharge cycling. The significant improvements resulting from these innovations are: extended cycle life; enhanced thermal, electrolyte, and oxygen management; and accommodation of nickel electrode expansion. The advanced cell design is in the process of being validated using real time LEO cycle life testing of NWSC, Crane, Indiana. An update of validation test results confirming this technology is presented.
Advanced recycling enables the application of post-use plastics (PUP) to produce valuable industrial chemicals and develop markets for recycled feedstocks. Pyrolysis is one of the most common advanced recycling technologies undergoing industrial-scale implementation for converting PUP. This paper presents a life cycle analysis (LCA) to assess greenhouse gas (GHG) emissions, fossil energy, water consumption, and solid waste impacts of converting PUP into new plastics such as high-density and low-density polyethylene (HDPE and LDPE, respectively). Data was collected from eight plastic pyrolysis companies. This study addresses the impacts of pyrolysis plant size and maturity; two substitution rate (SR) cases of pyrolysis oil with fossil-derived feedstocks in steam crackers (5% and a 20% of pyrolysis oil SR); and potentially avoided emissions from traditional end-of-life (EOL) management. Because the conventional feedstock slate of steam crackers in the Unites States is comprised of 94% gases (a mix of ethane, propane, and butane) and 6% naphtha, the 5% SR case looked at polyethylene (PE) derived from 5% pyrolysis oil, 1% naphtha, and 94% gases; while the 20% SR looked at PE derived from 20% pyrolysis oil and 80% gases. Moreover, the results are presented from two perspectives: 1) steam crackers' and 2) plastic recyclers'. In the recyclers' perspective, the results for the 5% SR showed for each kg of PUP used there was a 23% and 18% decrease in GHG emissions for HDPE and LDPE respectively, while the 20% SR showed a 4% and 3% reduction in GHG emissions for HDPE and LDPE respectively compared to virgin plastic. The 20% SR has lower GHG emissions reductions because there is an added step of hydrotreating the pyrolysis oil to remove chlorine concentrations that is not included in the 5% SR scenario. Furthermore, the 5% SR removes most of the naphtha, a more carbon intense feedstock, and replaces it with PUP-based pyrolysis oil, a less carbon intense feedstock. GHG emissions for PUP pyrolysis could be further reduced by 50% and 131% in the United States and European Union respectively if the GHG emissions of current PUP incineration practices were considered as emission reductions credits.
Hydrogen is gaining prominence as a key factor in the world's transition to a cleaner energy future. The International Energy Agency (IEA)'s Global Hydrogen Review 2023 reports that the number of low-emission hydrogen production projects is increasing rapidly. The potential for growth in new applications such as heavy industry, transportation, and power generation is significant. The IEA urges more decisive action to spur demand for low-emission hydrogen to achieve climate goals. While hydrogen is produced through various industrial methods, each with its own advantages and disadvantages, low-carbon hydrogen is critical for mitigating climate change and is incentivized by the Clean Hydrogen Production Tax Credit (45V). To this end, we have evaluated a commercial technology that can produce low- or negative-carbon hydrogen via ethanol catalytic oxidative reforming. This study assessed life cycle greenhouse gas emissions (carbon intensity or CI) associated with the hydrogen production technology. A total of 24 scenarios were evaluated, encompassing (a) Gen1 versus Gen2 ethanol inputs, (b) carbon capture and sequestration (CCS) of upstream fermentation CO2, and (c) oxygen sourcing via air separation unit (ASU) versus purchased or on-site production of oxygen as a byproduct of hydrogen electrolysis with a proton exchange membrane (PEM). Key findings include that the base case CI for hydrogen production using Gen2 ethanol from corn stover is lower than Gen1 dry mill corn ethanol. The study also points out that the CI for hydrogen production using PEM-O2 is lower than that using ASU-O2, whether the PEM-O2 is produced on-site or off-site (importing). When sourcing oxygen from on-site PEM-O2, the Gen1 and Gen2 ethanol-derived hydrogen exhibit favorable net-negative CI values for all evaluated scenarios, especially if the upstream ethanol CCS is included. As a reference, the 45V regulatory threshold for generating clean hydrogen tax credits is a CI below 0.45 kg CO2e/kg hydrogen.
Evolution of Extravehicular Mobility Unit (EMU) technology is necessary to support the Extravehicular Activity (EVA) requirements of the Space Station Freedom Program and those of the Space Exploration Initiative (SEI). Key qualities supporting long-duration missions include technologies that are highly reliable, durable, minimize logistics requirements, and are in-flight maintainable and serviceable. While these qualities are common to SSF and SEI EVA, development paths will differ where specific mission requirements impose different constraints. Development of reusable, regenerative technologies is necessary to minimize the logistics penalties. Increased battery discharge/recharge cycle life and usable wet life, compact high current density fuel cells, reusable CO2 absorbing media, and thermal radiation coupled with venting heat rejection technologies are just some methods of reducing consumables. Development must strive for durable, reliable systems that are in-flight serviceable and maintainable, which are vital for missions where logistics capabilities are extremely constrained. Key areas include suit components (e.g., gloves, boots, and cooling garments), and life support hardware such as fans, pumps, instrumentation, and emergency O2 systems. Higher pressure suits will reduce EVA prebreathe requirements and pre-EVA operations overall. Many challenges of higher pressure suits have been addressed by on-going development. Emphasis on glove development is necessary to provide low fatigue, dexterous glove mobility at higher suit pressures. Minimum impact hooks and scars which support an advanced SSF EMU have been identified. These accommodations permit upgrades that support servicing of low volume, high pressure oxygen systems, and hydrogen technologies such as fuel cell, and venting hydrogen heat rejection systems.
Directed energy deposition (DED) additive manufacturing (AM) has been recognized as an efficient and sustainable technology in the field of advanced manufacturing. In the past few years, Considerable discussion has been made by researchers to promote DED AM for better performance in manufacturing. The discussions focus on basic theoretical research, process optimization and control, technology innovation, and industrial applications. However, this technology׳s environmental and economic benefits over traditional manufacturing processes are still to be seen and its sustainability is also a mystery. Here, this chapter presents a critical overview of the environmental sustainability of DED to provide a comprehensive understanding of the effects of materials, processing conditions, and geometric complexities on the energy consumption and environmental impacts of DED and provide a better guide for decision-makers in terms of selecting suitable manufacturing processes. In addition, this chapter proposes a novel framework for DED AM sustainability assessment and improvement based on the Life Cycle Assessment (LCA) method and multi-objective optimization. At last, future perspectives and recommendations for the sustainability of DED AM are put forward.
Recycling spent lithium-ion batteries (LIB) could potentially bridge the ever increasing supply and demand gap for critical metals and simultaneously facilitate the management of hazardous battery waste. This study investigated the optimization of gluconic acid-based bioleaching technology through design of experiments (DOE), combined with techno-economic analysis (TEA), and life cycle assessment (LCA) with the aim of maximizing the net present value (NPV) and minimizing global warming impacts of the process. Biolixiviant containing predominantly gluconic acid produced by the genetically engineered (ΔpstS, P 112 :mgdh) Gluconobacter oxydans B58 through fermentation using non-recyclable paper as a growth substrate was used for the LIB leaching. At optimal bioleaching conditions of gluconic acid (160 mM), leaching time (2.5 h), reducing agent FeSO 4 to metal, i.e., cobalt (Co), nickel (Ni) and manganese (Mn), mole ratio (0.88), temperature (55 °C) and pulp density (2.5 %), the leaching efficiency was 87 % 72 %, 94 %, and 88 % for Co, Ni, Mn and lithium (Li), respectively. TEA analysis confirmed that bioleaching plant with an annual black mass processing capacity of 10,000 metric tons and plant life of 30 years would be economically viable with an NPV and profit margin of $136 million and 11 %, respectively. The predicted carbon footprint of gluconic acid-based bioleaching for recovering 1 kg of Co (13.2 kg of CO 2 eq.) is lower compared to that of most state-of-the-art leaching technologies. Moreover, gluconic acid-based bioleaching effectively recovered target metals when tested for different black mass chemistries.
This Python module provides a public API (via the class and function definitions) for interacting with GreenDelta's openLCA (version 2) either directly (via the IPC server) or indirectly (via an exported JSON-LD zip file). It is a key piece in NETL's new life cycle assessment unit process library reporting template.