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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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Research and development at the National Renewable Energy Laboratory supports the U.S. Department of Energy's Vehicle Technologies Office in advancing efficient and sustainable transportation technologies that will improve energy efficiency, fuel economy, and mobility energy productivity, and will enable America to achieve a resilient, secure, clean, and affordable transportation future.
Research and development at the National Renewable Energy Laboratory supports the U.S. Department of Energy's Vehicle Technologies Office in advancing efficient and sustainable transportation technologies that will improve energy efficiency, fuel economy, and mobility energy productivity, and will enable America to achieve a resilient, secure, clean, and affordable transportation future.
District energy systems efficiently provide thermal energy to multiple buildings and facilities through a network of shared infrastructure. Frequently, district energy systems are centered around combined heat and power (CHP) plants that generate electricity as well as heating and cooling to the local buildings. By providing both electricity and thermal energy from a single fuel source and central location, these systems use less fuel, decrease energy and operational costs, and reduce the need for heating and cooling equipment in individual buildings.
District energy systems efficiently provide thermal energy to multiple buildings and facilities through a network of shared infrastructure. Frequently, district energy systems are centered around combined heat and power (CHP) plants that generate electricity, as well as heating and cooling, to the local buildings. By providing both electricity and thermal energy from a single fuel source and central location, these systems use less fuel, decrease energy and operational costs, and reduce the need for heating and cooling equipment in individual buildings.
District energy systems efficiently provide thermal energy to multiple buildings and facilities through a network of shared infrastructure. Frequently, district energy systems are centered around combined heat and power (CHP) plants that generate electricity as well as heating and cooling to the local buildings. By providing both electricity and thermal energy from a single fuel source and central location, these systems use less fuel, decrease energy and operational costs, and reduce the need for heating and cooling equipment in individual buildings.
Modular pressurized hotbox for use and substitution in a variety of pressurized electrochemical applications to include reversible solid oxide electrolyzer and fuel cells, energy storage systems, renewable fuel production, solid-state hydrogen pumping and liquefaction, and oxygen transport membranes. This is enabled by mixed electronic and ionic conducting compositions of vanadia-yttria and vanadia-calcia stabilized zirconia and a dry powder method of manufacture for ceramic core stacks.
Research and development at the National Renewable Energy Laboratory supports the U.S. Department of Energy's Vehicle Technologies Office in advancing efficient and sustainable transportation technologies that will improve energy efficiency, fuel economy, and mobility energy productivity, and will enable America to achieve a resilient, secure, clean, and affordable transportation future.
Research and development at the National Renewable Energy Laboratory supports the U.S. Department of Energy's Vehicle Technologies Office in advancing efficient and sustainable transportation technologies that will improve energy efficiency, fuel economy, and mobility energy productivity, and will enable America to achieve a resilient, secure, clean, and affordable transportation future.
Bicycloalkanes stand out as a replacement for aromatics from conventional jet fuel (CJF) because of their high energy density and lower freezing point. Most reports to date have focused on synthesizing bicycloalkanes using model compounds or single sugar components of lignocellulose. Here, we utilize all lignocellulosic sugars of corn stover (CS) to produce bicycloalkanes. First, furfural (FFR) and 5-hydroxymethyl furfural (5-HMF) are produced via acid-catalyzed dehydration, achieving combined FFRs molar yields ranging from 65% to 73%, respectively. The resulting FFRs are converted to cyclopentanones with molar yields within the range of 57%–63% via hydrogenation and Piancatelli rearrangement. Further aldol condensation of cyclopentanones yields C 10 -C 12 oxygenates with 80 mol %. Lastly, these oxygenates are directly hydrodeoxygenated to bicycloalkanes in a yield of 83.8 mol %. The resulting bicycloalkanes exhibit tier α fuel properties consistent with Jet A fuel (CJF) specifications and blend compatibility with CJF at a 37% volumetric ratio.
The HYBRID2 program which computes the fuel and energy consumption of a hybrid vehicle with a bi-modal control strategy over specified component driving cycles is described. Fuel and energy consumption are computed separately for the two modes of operation. The program also computes yearly average fuel and energy consumption using a composite driving cycle which varies as a function of daily travel. The modelling techniques are described, and subroutines and their functions are given. The composition of modern automobiles is discussed along with the energy required to manufacture an American automobile. The energy required to scrap and recycle automobiles is also discussed.
NASA's Vision for Exploration requires safe, human-rated, energy storage technologies with high energy density, high specific energy and the ability to perform in a variety of unique environments. The Exploration Technology Development Program is currently supporting the development of battery and fuel cell systems that address these critical technology areas. Specific technology efforts that advance these systems and optimize their operation in various space environments are addressed in this overview of the Energy Storage Technology Development Project. These technologies will support a new generation of more affordable, more reliable, and more effective space systems.
Abstract This study investigates the combustion performance of a CO2-rich fuel mixture containing ethane and methane as active species using a constant volume combustion chamber. This fuel is obtained as a byproduct of a chemical looping-based oxidative dehydrogenation (Cl-ODH) process ethylene production. The byproduct gas mixture has 40.79% CO2, 39.49% ethane, and 4.88% methane by weight with other minor compounds. Using this fuel for energy extraction would improve the process efficiency of the ethane to ethylene conversion. After initial combustion modeling, the gas fuel mixture was reduced to just the major species: CO2, ethane, and methane. The mixture was then tested for flammability limits and combustion performance under spark-ignition conditions. Effects of ambient conditions like temperatures between 300 and 400 K with initial pressures from 1 to 10 bar were tested. The effects of stoichiometry were tested to understand flame velocities and heat release. The fuel mixture showed an overall reduced flame velocity compared to gasoline. Instability in combustion was believed to be caused by the dissociation of ethane under elevated conditions. At higher pressures, the flame produces lower cumulative heat release. Simulations were also performed using a model tuned to replicate the operations of the combustion chamber used in the experiments. Heat release and unburnt fuel mass data were calculated to identify the discrepancies in the combustion completeness at elevated pressures. The effects of CO2 quenching the flame coupled with the increased dissociation of the fuel species can lead to up to more than 75% of the fuel mixture being unburnt. Data from this study were used to modify a small-scale spark-ignition engine to use this fuel and produce usable energy.
This study investigated the energy and cost savings potential by modeling a dual fuel heat pump system with its control for a residential building in (5A) cold climate in U.S. The simulation analysis showed that the application of the DFHP system and its control to the target building can save the heating energy by 42% over a gas furnace system (baseline system). Although the HP-only system can save more heating energy (i.e., 53%) over the baseline system than DFHP system does, the DFHP with its control demonstrated the higher cost savings when a time of use electricity rate was considered.
Today s widespread development of proton-exchange-membrane (PEM) fuel cell technology for commercial users owes its existence to NASA, where fuel cell technology saw its first applications. Beginning with the early Gemini and Apollo programs, and continuing to this day with the Shuttle Orbiter program, fuel cells have been a primary source of electrical power for many NASA missions. This is particularly true for manned missions, where astronauts are able to make use of the by-product of the fuel cell reaction, potable water. But fuel cells also offer advantages for unmanned missions, specifically when power requirements exceed several hundred watts and primary batteries are not a viable alternative. In recent years, NASA s Exploration Technology Development Program (ETDP) funded the development of fuel cell technology for applications that provide both primary power and regenerative fuel cell energy storage for planned Exploration missions that involved a return to the moon. Under this program, the Altair Lunar Lander was a mission requiring fuel cell primary power. There were also various Lunar Surface System applications requiring regenerative fuel cell energy storage, in which a fuel cell and electrolyzer combine to form an energy storage system with hydrogen, oxygen, and water as common reactants. Examples of these systems include habitat modules and large rovers. In FY11, the ETDP has been replaced by the Enabling Technology Development and Demonstration Program (ETDDP), with many of the same technology goals and requirements applied against NASA s revised Exploration portfolio.
Today's energy system uses a variety of fuels and energy carriers in molecular forms, such as coal, oil, and natural gas, each contributing to CO2 emissions (Figure 1). As solar and wind levels grow and the energy system becomes more electrified, fossil molecular fuels will contribute a progressively smaller fraction of overall energy. As shown in Figure 2, hydroelectric storage and molecules, such as coal and natural gas, provide substantial storage and dispatch functionality today that will become increasingly critical for electricity operation and stability. Emerging low-carbon gases, such as hydrogen, can support the efficient integration of renewables in the transition from today's energy system to one that is 100% clean from a carbon emissions perspective.
Using torrefied char, or biocoal, as solid fuel provides an opportunity to introduce a sustainable feedstock into the energy market. The goals of this study were to investigate how torrefaction improves the energy content and the grindability of a Malaysian bamboo along with understanding the potential for integrated energy recovery from torrefaction gases. The feedstock was torrefied at 250–290 °C for 1 h and the combustion characteristics and grindability of the solid products along with the composition of torrefied gas species were measured. The results showed a beneficial increase in elemental carbon increased from 47 to 63 wt% at 290 °C torrefaction, reflecting an increase in higher heating value from 17.8 to 25.6 MJ/kg. The combustion behavior of all the products appeared to show three distinct combustion zones; however, torrefaction severity leading to higher combustion temperature and time as the fixed carbon augmented with the increase of torrefaction temperature. This increase in severity also lead to more friable and grindable material, and the 290 °C condition required a factor of 2.7 less hold-up time in the mill compared to the raw bamboo, and a factor of 8.5 less energy (938 and 111 kWh/tonne respectively). Through analysis of the gas and volatile formation, a case study showed that catalytic oxidation can convert nearly 100% of the embodied chemical energy into usable thermal energy. These experimental findings were scaled to a 100,000 tonne/y capacity torrefaction plant and in the moderate case of 270 °C operating temperature, the plant has 1.25 GJ/tonne excess energy beyond what the process needs.
GTI Energy has integrated the Cool Reformer technology with the IH 2® -50 pilot plant (which can process a maximum of 50kg/day of biomass feed) to demonstrate the suitability of this new reforming technology for producing hydrogen within IH 2 ® process. As part of this study, we showed that all of the hydrogen required for the IH 2® process could be produced from steam reforming the IH 2® light gas generated within the process and the system can be integrated in a cost-effective way compared to the use of standard SMRs.
Because natural gas emits less carbon than other fossil fuels, it holds promise as a green energy transition fuel. However, the overall carbon footprint of natural gas is significantly elevated by methane emissions that occur during its production and transmission (Cusworth et al. 2022). Methane “super-emitters,†while comprising only about 1% of sites, are responsible for the majority of oil- and gas-sourced methane emissions, making their detection and mitigation critical in reducing the climate impact of natural gas and in meeting national and global sustainability goals (Sherwin et al. 2024). Yet, despite advancements in detection, significant uncertainties remain regarding the size, frequency, and duration distributions of methane emissions (e.g., Frankenberg et al. 2016, Cusworth et al. 2022, Chen, Sherwin et al. 2022, Conrad et al. 2023, Johnson et al. 2023, Sherwin et al. 2024) underscoring the need for comprehensive emissions inventories segmented by basin across the US. Airborne surveys are well-suited for collecting data to build these comprehensive, basin-level inventories because they allow for extensive spatial coverage, and have the spatial resolution, and the sensitivity to pinpoint individual methane sources. As remote sensing technologies enable rapid basin-scale surveys, it is imperative to establish scientifically and statistically robust standards to generate reliable and actionable emissions inventories. Recent work has shown that differences in airborne sampling strategies, detection technologies, and analysis can lead to large differences between survey conclusions if not correctly accounted for (Chen et al. 2024). This elevates the importance of incorporating proper sampling and analysis techniques when designing a methane emissions monitoring campaign to produce accurate results and facilitate cross-study comparisons. In this paper, we describe a survey strategy designed using the latest conclusions from the literature to align results from different aerial surveys. We identify several sampling and analysis principles, including large sample sizes, balanced sampling across oil and gas production, careful survey area definition, and a unified protocol for analysis, to be vital to producing an unbiased estimate of basin-scale emissions. We present results from a Department of Energy-funded project that deployed this survey strategy in two understudied oil and gas- producing regions in the United States: the Haynesville Basin in Texas and Louisiana, and the Woodford Shale in the Anadarko Basin in Oklahoma.