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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 1,387 records · Page 77
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Evaluation of Energy Efficiency Performance of Heated Windows

Fenestration systems are widely used across the world. There is expansive research on window configurations, frames, and glazing technology, but not enough research has been published on reducing window heat loss through heat application to a pane. The presented study attempted to evaluate the performance of heated windows by developing an experimental setup to test a window at various temperatures by varying the power input to the window. Heated double pane window was installed in an insulated box. A temperature gradient was developed across the window by cooling one side of the window using gel-based ice packs. The other face of the window was heated by enabling power at different wattages through the window. The temperature of the inside and outside panes, current and voltage input, and temperature of the room and box were recorded. The data was used to calculate the apparent effective resistance of the window when not being heated vs. when being heated. The study concluded that, when window temperature was maintained close to the room temperature, the heated double pane window is effective in reducing heat loss by as much as 50% as compared to a non-heated double pane window. When temperature of the window was much higher than the room temperature, the heat loss through the window increased beyond that of a non-heated window. The issues encountered during the current stages of experiments are noted, and recommendations are provided for future studies.

42 ENGINEERING↗
DOE OSTI2014

Energy efficient microwave synthesis of mesoporous Ce 0.5 M 0.5 O 2 (Ti, Zr, Hf) nanoparticles for low temperature CO oxidation in an ionic liquid – a comparative study

Ce 0.5 M 0.5 O 2 (M = Ti, Zr, Hf) nanoparticles have been successfully synthesized by microwave irradiation in the ionic liquid [C 4 mim][Tf 2 N] (1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide). The morphology, crystallinity, and chemical composition of the obtained materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), Raman spectroscopy, and N 2 –adsorption measurements. XRD and Raman spectroscopy analyses confirmed the formation of solid solutions with cubic fluorite structure. The catalytic activities of the Ce 0.5 M 0.5 O 2 (M = Ti, Zr, Hf) nanoparticles were investigated in the low-temperature oxidation of CO. Ce 0.5 Zr 0.5 O 2 nanospheres exhibit the best performance (100% conversion at 350 °C), followed by Ce 0.5 Hf 0.5 O 2 (55% conversion at 360 °C) and Ce 0.5 Ti 0.5 O 2 (11% conversion at 350 °C). Heating the as-prepared Ce 0.5 Zr 0.5 O 2 to 600 °C for extended time leads to a decrease in surface area and, as expected decreased catalytic activity. Depending on the ionic liquid the obtained Ce 0.5 Zr 0.5 O 2 exhibits different morphologies, varying from nano-spheres in [C 4 mim][Tf 2 N] and [P 66614 ][Tf 2 N] (P 66614 = trishexyltetradecylphosphonium) to sheet-like assemblies in [C 3 mimOH][Tf 2 N] (C 3 mimOH = 1-(3-hydroxypropyl)-3-methylimidazolium). As a result, the microwave synthesis superiority to other heating methods like sonochemical synthesis and conventional heating was proven by comparative experiments where the catalytic activity of Ce 0.5 Zr 0.5 O 2 obtained by alternate methods such as conventional heating was found to be poorer than that of the microwave-synthesised material.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Energy efficient solvent regeneration process for carbon dioxide capture

A process for removing carbon dioxide from a carbon dioxide-loaded solvent uses two stages of flash apparatus. Carbon dioxide is flashed from the solvent at a higher temperature and pressure in the first stage, and a lower temperature and pressure in the second stage, and is fed to a multi-stage compression train for high pressure liquefaction. Because some of the carbon dioxide fed to the compression train is already under pressure, less energy is required to further compress the carbon dioxide to a liquid state, compared to conventional processes.

03 NATURAL GAS↗
DOE OSTI2013

Energy-Saving Melting and Revert Reduction (E-SMARRT): Energy Efficiency Instrumentation

As with any manufacturing operation, the metalcasting processes have several sources of variation. Additionally, the metalcasting industry routinely produces a wide variety of complex shaped components, which often exacerbates the problem of determining the source of variation. The goals of this project were to develop better tools and strategies to collect and manage process and product information. Based on industry feedback, five areas were selected based on the amount of variation caused by this source or the potential for improvement in terms of energy, emissions and competitiveness. These five areas were: 1. Heat Treatment Control Strategies 2. Semi-Automated Grinding 3. Surface Mapping Software 4. Study of Impact of Repairs via Weld Gouges 5. Rapid Pattern Making Machine. This project collectively looked at areas of the steel casting production process which could help reduce the rework, scrap and energy consumption required. Through these efforts, casting producers are better equipped to control their processes and specify processes that better meet their customers’ needs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2015

Northwest Energy Efficient Manufactured Housing Program High-Performance Test Homes

This project represents the third phase of a multi-year effort to develop and bring to market a High Performance Manufactured Home (HPMH). The scope of this project involved building four HPMH prototypes, resulting in what is expected to be a 30% savings relative to the Building America Benchmark. (The actual % savings varies depending on choice of heating equipment and climate zone). The HPMH home is intended to make significant progress toward performing as zero-net-energy ready. Previous phases of this project created a HPMH specification and prototyped individual measures from the package to obtain engineering approvals and develop preliminary factory construction processes. This report describes the project team's work during 2014 to build prototype homes to the HPMH specifications and to monitor the homes for energy performance and durability during 2014. Monitoring is expected to continue into 2016.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2019

Manufacturing of Advanced Alnico Magnets for Energy Efficient Traction Drive Motors CRADA Final Report

The primary theme of this Technology Commercialization Fund (TCF) project was refining the pre-alloyed powder processing approach (with alnico 8, modified for higher coercivity) of that came out of the previous Development of Radically Enhanced alnico Magnets (DREaM) project to permit full size net-shape alnico magnets to be produced in a reproducible manner that could allow testing in an advanced Permanent Magnet (PM) drive motor. Previously, a lack of sufficient coercivity in alnico magnets limits their energy product and their application in automotive traction drive motors, despite their high temperature stability. Use of enhanced sintered alnico magnets, instead of rare earth (RE) magnets or larger cast alnico magnets, could lower costs and decrease cooling needs of these motors. Conventional production of the best (aligned) alnico magnets (alnico 9) involves costly directional solidification (DS) and achieves good alignment, but modest energy product (10 MGOe), because of low coercivity. Other limitations of cast alnico 9 magnets are poor mechanical properties and difficulty in scaling special casting molds to mass production. In spite of these problems with alnico 9, a commercial electric motor company, UQM, developed a fully capable traction drive motor that met many 2022 DOE-VTO performance targets, except full speed operation, due to brittle mechanical behavior. While UQM demonstrated an advanced drive motor that used alnico 9, they also encouraged the development of improved alnico, especially for greater coercivity (seeking 2X) and improved mechanical properties. While commercial sintered alnico magnets are less brittle and have improved coercivity, they have an inferior energy product due to their non-aligned, fine-grained microstructure. Thus, full development and up-scaling of well-aligned alnico magnets with a further increase in coercivity and good mechanical properties by a low cost powder processing route became the theme of this TCF project. The processing route for this project involved high-pressure gas atomization, at Ames and Carpenter, of modified alnico 8 compositions, compression molding of the resulting pre-alloyed powders into bulk samples, de-binding and sintering the samples to full density, and a final magneto-thermal treatment of the resulting bulk magnets, at Ames and Arnold Magnetic Technologies, to produce aligned magnets, which were intended for motor testing at UQM and Ford.

42 ENGINEERING↗
DOE OSTI2023

Energy-efficient cooperative resource allocation and task scheduling for Internet of Things environments

Offloading Internet of Things (IoT) tasks to the cloud for further processing might not always lead to an optimal execution time, particularly in situations such as resource contention, under-provisioning, over-provisioning, and fragmentation. In addition, dynamically optimizing the number of Virtual Machines (VMs) for resource scheduling in order to meet application requirements remains a major research challenge. Further, existing resource scheduling algorithms focus primarily on minimizing operational costs while maximizing resource sharing and utilization. Considering energy utilization as part of the resource allocation and scheduling process as an optimization objective for maintaining load balancing has often been neglected. To address these challenges and more, we propose a cooperative energy-aware resource allocation and scheduling strategy based on a Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) multi-criteria decision-making method. Here we used the Grid Workloads Archive dataset to evaluate our proposed approach named TOPREAL. Experimental results with respect to the allocation of VM resources when considering processing a large segment of tasks indicate that TOPREAL outperforms existing algorithms in terms of energy savings, with an average improvement of 40.25%, while maintaining an average improvement of 16.21% when it comes to execution time. Results also demonstrate that our method can save an average of 78.06 processing hours and 63,215kJ of energy when compared to existing scheduling algorithms. These results demonstrate the effectiveness of our proposed model and the viability of using multi-criteria decision-making techniques such as TOPSIS to solve the resource allocation and scheduling problem in edge environments.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2014

Contributing to Net Zero Building: High Energy Efficient EIFS Wall Systems

The team led by Dow Corning collaborated to increase the thermal performance of exterior insulation and finishing systems (EIFS) to reach R-40 performance meeting the needs for high efficiency insulated walls. Additionally, the project helped remove barriers to using EIFS on retrofit commercial buildings desiring high insulated walls. The three wall systems developed within the scope of this project provide the thermal performance of R-24 to R-40 by incorporating vacuum insulation panels (VIPs) into an expanded polystyrene (EPS) encapsulated vacuum insulated sandwich element (VISE). The VISE was incorporated into an EIFS as pre-engineered insulation boards. The VISE is installed using typical EIFS details and network of trained installers.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2019

Hygrothermal analyses of the moisture control and energy efficiency potential of an adaptive water-resistive barrier for building envelopes

A water-resistive barrier (WRB) is a material installed on the exterior side of the sheathing to prevent water intrusion so that building components are not damaged by moisture. A membrane that can change its water vapor permeability between two states to control water vapor transport into and out of residential and commercial building wall systems is being developed. This simulation study assesses if this membrane used as a WRB reduces moisture levels and mold growth risk in exterior walls and building energy consumption. The developed membrane may require modifications to fully function as a WRB in contact with liquid water. Hygrothermal component simulations were conducted for different climate zones, different wall assemblies, different switching points and permeabilities to identify the most beneficial application cases and their required perm range and switching control. The study details the required simulation settings and suggests that the switchable membrane can reduce the water content in the sheathing and reduce the mold growth risk in the cavity in all climate zones. The effect on energy consumption of the switchable membrane is not significant. The study also includes recommendations on how to model the material characteristics of a switchable membrane and recommendations on practical applications for the switchable membrane.

42 ENGINEERING↗
DOE OSTI2023

The Integration of Wi-Fi Location-Based Services to Optimize Energy Efficient Commercial Building Operations

This project investigated and demonstrated the use of Wi-Fi Location-Based Services (LBS) to perform occupancy sensing in commercial buildings. Wi-Fi LBS can be used to detect the presence of Wi-Fi enabled mobile devices and laptops that accompany occupants as they move through the building. These signals can be used to determine occupant presence, head count, and location. When integrated with the building automation system, this emerging technology approach can be used to manage other connected systems such as lighting and HVAC to reduce energy usage in the building and improve occupant comfort. An open source location detection algorithm was developed, which uses data collected from three or more Wi-Fi access points to determine the presence and estimate the location of mobile devices and laptops. Access points can detect Wi-Fi enabled devices even if they are not connected to the existing Wi-Fi network. Building occupancy is determined based on the presence, location, and movement of these devices through the space. From lab and small-scale in-situ testing, the Location Detection Algorithm (LDA) was found to be accurate to within 10 feet and could be further refined by tuning the algorithm for the specific space characteristics such as layout and obstructions (walls, furniture, etc.). An open source method to integrate the occupancy data with existing building automations systems was investigated. The Wi-Fi occupancy sensing approach was then demonstrated and validated at commercial buildings located in Saint Paul, MN; Madison, WI; New York City; and Fort Worth, TX.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2025

Compressed Air Scoping Tool Teaches Energy Efficiency Best Practices

Standards and practices around compressed air systems are evolving as previous golden rules become outdated and unhelpful. One of the most referenced guidelines gives us the perfect example: The previous rule of thumb for compressed air storage – 1-3 gal/cfm1,2 – is now accepted to be 3-5 gal/cfm. This change in recommended storage is only one of many in the industry, resulting in industrial users lost in a sea of contradictory best practices. To help combat confusion and poor information sharing, a collaborative effort between Oak Ridge National Laboratory (ORNL) and the Department of Energy’s (DOE’s) Better Plants program created the Compressed Air (CA) Scoping Tool with the most up-to-date best practices in the industry (as of 2023). It can be used as a nonbiased, one-stop shop for best practice recommendations. The Excelbased tool is designed to be an initial step in understanding the operation of a compressed air system, a baselining tool enabling users to comprehend various aspects of a facility’s system from the production of compressed air to its application by end users.

42 ENGINEERING↗
DOE OSTI2024

3D printed carbon fiber reinforced carbon as an energy efficient alternative to graphite for EFAS tooling

As Electric Field Assisted Sintering (EFAS) gains more industrial acceptance and use, it becomes more important to develop more efficient means to implement this technology. To this aim, 3D printed continuous carbon fiber reinforced carbon (CCC) was manufactured and fabricated into tooling for EFAS systems as an alternative to traditional graphite tooling. The impact of fiber orientation on the thermal and electrical properties of the CCC was characterized. Sample material was sintered in Tokai G535 graphite tooling, under common processing conditions and compared with CCC tooling. There was nearly 50 % energy savings compared to graphite while maintaining equivalent sample density and microstructure plus keeping ram temperatures 39 % cooler. This is due to spatial control of generated heat and thermal diffusivity within the molds, by means of fiber orientation anisotropy. Finite element modeling of the tooling design supported the experimental results as well as displays the effect of optimization of this 3D printed CCC material.

36 MATERIALS SCIENCE↗
DOE OSTI2025

High‐Performance Low‐Emissivity Paints Enabled by N‐Doped Poly(benzodifurandione) (n‐PBDF) for Energy‐Efficient Buildings

Abstract Low‐emissivity (low‐e) paints reduce radiative heat exchange between buildings and the environment, stabilizing indoor climates and lowering air conditioning demand. However, low‐cost, durable, and colored low‐e paints have yet to be demonstrated. Here, an approach is proposed using n‐doped poly(benzodifurandione) (n‐PBDF), a transparent organic conducting polymer, coated over colored commercial paints. This achieves a low thermal emissivity of 0.19 in the mid‐infrared spectrum, attributed to the efficient charge transport of delocalized π‐electrons in n‐PBDF structure. The reduction in thermal emissivity aids in regulating building temperatures by minimizing heat transfer between buildings and their surroundings across diverse climate zones and seasons. The n‐PBDF coating preserves the underlying paint's color due to its high visible transparency, meeting aesthetic requirements. It also shows strong stability in accelerated indoor weathering tests, ensuring long‐term performance. Simulations estimate annual HVAC energy savings of over 10,800 kWh in San Francisco and 5,500 kWh in Chicago for the typical mid‐rise apartments. The paint's versatility, scalability, and durability make it suitable for buildings, vehicles, and greenhouses, aiding urban heat island mitigation.

Liu, Xiaojie [School of Mechanical Engineering and↗
DOE OSTI2017

Chapter 6: Residential Lighting Evaluation Protocol. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures

Given new regulations, increased complexity in the market, and the general shift from CFLs to LEDs, this evaluation protocol was updated in 2017 to shift the focus of the protocols toward LEDs and away from CFLs and to resolve evaluation uncertainties affecting residential lighting incentive programs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2020

Testing molecules that disperse biofilms and biofouling and improve water recycling energy efficiency

In collaboration with Aequor, Inc, ABPDU researchers have evaluated a number of antibiofouling compounds for biofilm reduction potential in biomanufacturing applications. In addition to verifying their efficacy as dispersants, studies with bacteria, fungi, and algae indicate compatibility with canonical industrial host organisms. In addition, these molecules were found to significantly enhance growth rates of heterotrophic algae, indicating potential applications in algal cultivations.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2024

RACEE: Port Lions Community Energy Efficiency Project

The City of Port Lions is one of several villages located on Kodiak Island in the Gulf of Alaska. Founded in 1964, Port Lions was built through the joint efforts of the Bureau of Indian Affairs, Lions International, the Public Health Service, and other organizations for the displaced residents of Afognak which was destroyed by a tsunami caused by the Good Friday Earthquake.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗