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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 883 records · Page 49
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Measured transonic unsteady pressures on an energy efficient transport wing with oscillating control surfaces

Highlight results are presented from subsonic and transonic pressure measurement studies conducted in the Langley Transonic Dynamics Tunnel on a supercritical wing model representative of an energy efficient transport design. Steady- and unsteady-pressure data were acquired on the upper and lower wing surface at an off-design Mach number of 0.60 and at the design Mach number of 0.78, for a Reynolds number of 2.2 x 10(6) (based on the wing average chord). The model configuration consisted of a sidewall-Mounted half-body fuselage and a semi-span wing with an aspect ratio of 10.76, a leading-edge sweepback angle of 28.8 degrees, and supercritical airfoil sections. The wing is instrumented with 252 static pressure orifices and 164 dynamic pressure gages. Model test variables included wing angle of attack, control-surface mean deflection angle, control-surface oscillating deflection angle and frequency, and phasing between oscillating leading-edge and trailing-edge controls when used together.

Cazier, F. W., Jr.↗
DOE OSTI2018

The Cost of Saving Electricity Through Energy Efficiency Programs Funded by Utility Customers: 2009–2015

The average cost to utilities to save a kilowatt-hour (kWh) in the United States is 2.5 cents, according to the most comprehensive assessment to date of the cost performance of energy efficiency programs funded by electricity customers. These costs are similar to those documented earlier. Cost-effective efficiency programs help ensure electricity system reliability at the most affordable cost as part of utility planning and implementation activities for resource adequacy. Building on prior studies, Berkeley Lab analyzed the cost performance of 8,790 electricity efficiency programs between 2009 and 2015 for 116 investor-owned utilities and other program administrators in 41 states. The Berkeley Lab database includes programs representing about three-quarters of total spending on electricity efficiency programs in the United States.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2019

Improved Performance of Polyurethane Foam Insulation Using Ingeo Biopolymer Liners and its Impact on Energy Efficiency of Refrigerator and Freezers

This paper compares the effect of isothermal aging of the thermal conductivity of polyurethane foam in simulated refrigerator-freezer panels made from polylactic acid biopolymer from NatureWorks (IngeoTM) and high-impact polystyrene. Specimens were aged at room temperature and thermal conductivity measurements were made at 10°C over a period of 2.4 years. The energy use over the life of refrigerator-freezer is also calculated using the Energy-Efficient Refrigerator Analysis program which was developed by the United States Department of Energy to estimate the energy savings potential of various technology option upgrades (cabinet and refrigeration system) for rulemaking purposes. The results show that energy savings from implementing the Ingeo liner range from 818 to 1395 kWh (7 to 13% of total energy use) over a 15-year period.

Hossieny, Nemat↗
DOE OSTI2017

Chapter 8: Whole-Building Retrofit with Consumption Data Analysis Evaluation Protocol. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures

Whole-building retrofits involve the installation of multiple measures. Whole-building retrofit programs take many forms. With a focus on overall building performance, these programs usually begin with an energy audit to identify cost-effective energy efficiency measures for the home. Measures are then installed, either at no cost to the homeowner or partially paid for by rebates and/or financing. The methods described here may also be applied to evaluation of single-measure retrofit programs. Related methods exist for replace-on-failure programs and for new construction, but are not the subject of this chapter.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
NASA NTRS1989

Longitudinal aerodynamic characteristics of a subsonic, energy-efficient transport configuration in the National Transonic Facility

The Reynolds number, aeroelasticity, boundary layer transition, and nonadiabatic wall temperature effects, and data repeatability was determined in the National Transonic Facility (NTF) for a subsonic, energy efficient transport model. The model was tested over a Mach number range of 0.50 to 0.86 and a Reynolds number range of 1.9 million to approximately 23.0 million (based on mean geometric chord). The majority of the data was taken using cryogenic nitrogen (data at 1.9 million Reynolds number was taken in air). Force and moment, wing pressure, and wing thermocouple data are presented. The data indicate that increasing Reynolds number resulted in greater effective camber of the supercritical wing and horizontal tail, resulting in greater lift and pitching moment coefficients at nearly all angles of attack for M = 0.82. As Reynolds number was increased, untrimmed L/D increased, the angle of attack for maximum L/D decreased, drag creep was reduced significantly, and drag divergence Mach number increased slightly. Data repeatability for both modes of operation of the NTF (air and cryogenic nitrogen) was generally very good, and nonadiabatic wall effects were estimated to be small. Transition-free and transition-fixed configurations had significantly different force and moment data at M = 0.82 for low Reynolds number, and very small differences were noted at high Reynolds numbers.

Jacobs, Peter F.↗
DOE OSTI2019

Way to increase the energy efficiency of the distillation unit at ethylbenzene manufacturing technology

The object of research is the installation of rectification columns for benzene, ethylbenzene, and polyalkylbenzenes. The purpose of this work is an optimization of rectification technological modes and energy efficiency increasing of distillation in the technology of ethylbenzene production by replacing of the used in reboilers vapor at 4 MPa by vapor at 2 MPa. The proposed optimization option of the rectification unit is efficient since the implementation of the proposed technical solution will be achieved using Vapor 2 with increased efficiency of the process, namely a reduction of vapor consumption. The total consumption of vapor after the upgrade will be 2.751 Gcal / hour, which is 2168 Gcal per year less than the current vapor load.

09 BIOMASS FUELS↗
DOE OSTI2022

Energy efficiency for the growing South Carolina manufacturing industries. Final Report

The overall goals of the proposed project were to establish a DOE Industrial Assessment Center with Clemson University as the main center and to cement the Clemson IAC as the "go to" resource for energy efficiency expertise and assistance to manufacturing businesses in the state of South Carolina. The Clemson IAC included a satellite support center through partnership with the SCE&G Energy Innovation Center at the Clemson University Restoration Institute (CURI) in North Charleston, SC. The Clemson IAC was the first IAC based in the state with the goal to serve the entire state. The Clemson IAC provided SMEs with no-cost energy assessments, trained the next generation of energy-savvy engineers, and provided outreach to non-participating SMEs. Project objectives were structured into five 12-month Budget Periods. In the first Budget Period, the primary objective was to establish methods and materials for Clemson IAC assessments, training, and outreach. In the remaining Budget Periods, the primary objectives were to perform assessments, train students, and pursue outreach to hard-to-reach SMEs that did not participate in energy assessments. Expected outcomes in the first Budget Period included the development of standard procedures for performing energy assessments, including data acquisition, processing, and communication both within the team and in assessment reports prepared for SMEs. Outcomes related to student training in the first Budget Period included detailed curriculum and internship plans for students pursuing the DOE IAC Certificate and energy-related Clemson University certificates. Outcomes in the first Budget Period also included the development of outreach materials and plans for outreach events. In Budget Periods 2 through 5, major expected outcomes are trained students and completed energy assessments and reports for SMEs. Decision points and Go-No Go criteria for the end of each Budget Period, presented in more detail below, are based on the number of students in training and the number of energy assessments performed.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2023

Rapid and Energy‐Efficient Synthesis of Disordered Rocksalt Cathodes

Abstract Lithium‐rich transition metal oxides with a cation‐disordered rocksalt structure (disordered rocksalt oxides or DRX) are promising candidates for sustainable, next‐generation Li‐ion cathodes due to their high energy densities and compositional flexibility, enabling Co‐ and Ni‐free battery chemistries. However, current methods to synthesize DRX compounds require either high temperature (≈1000 °C) sintering for several hours, or high energy ball milling for several days in an inert atmosphere. Both methods are time‐ and energy‐intensive, limiting the scale up of DRX production. The present study reports the rapid synthesis of various DRX compositions in ambient air via a microwave‐assisted solid‐state technique resulting in reaction times as short as 5 min, which are more than two orders of magnitude faster than current synthesis methods. The DRX compounds synthesized via microwave are phase‐pure and have a similar short‐ and long‐range structure as compared to DRX materials synthesized via a standard solid‐state route, resulting in nearly identical electrochemical performance. In some cases, microwave heating allows for better particle size and morphology control. Overall, the rapid and energy‐efficient microwave technique provides a more sustainable route to produce DRX materials, further incentivizes the development of next‐generation DRX cathodes, and is key to accelerating their optimization via high‐throughput studies.

25 ENERGY STORAGE↗
DOE OSTI2017

The Transforming Mobility Ecosystem: Enabling in Energy-Efficient Future

Over the next decade, the transportation sector is poised for rapid change, propelled toward a new mobility future by strong technology currents and the confluence of prevailing megatrends. These major forces hold the promise of shaping a new mobility future – one that unlocks tremendous economic value, provides unprecedented gains in safety, offers affordable and equal accessibility, and enables the transition to energy-efficient transport of people and goods. They come, however, with cautionary viewpoints on energy consumption of the entire sector, necessitating the need to carefully guide the emergent future. This report examines four possible mobility futures that could exist in 2050 and the positive and negative impacts of these futures on energy consumption and the broader economy.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2019

Evolving Energy Efficient Convolutional Neural Networks

As deep neural networks have been deployed in more and more applications over the past half decade and are finding their way into an ever increasing number of operational systems, their energy consumption becomes a concern whether running in the datacenter or on edge devices. Hyperparameter optimization and automated network design for deep learning is a quickly growing field, but much of the focus has remained only on optimizing for the performance of the machine learning task. In this work, we demonstrate that the best performing networks created through this automated network design process have radically different computational characteristics (e.g. energy usage, model size, inference time), presenting the opportunity to utilize this optimization process to make deep learning networks more energy efficient and deployable to smaller devices. Optimizing for these computational characteristics is critical as the number of applications of deep learning continues to expand.

Young, Steven↗
NASA NTRS2012

Energy Efficient Cryogenics on Earth and in Space

The Cryogenics Test Laboratory, NASA Kennedy Space Center, works to provide practical solutions to low-temperature problems while focusing on long-term technology targets for energy-efficient cryogenics on Earth and in space.

Fesmire, James E.↗
DOE OSTI2021

Human-in-the-loop Sensing and Control for Commercial Building Energy Efficiency and Occupant Comfort

Most of the existing heating, ventilation and air conditioning (HVAC) systems in commercial buildings operate in a conservative manner by assuming maximum occupancy in each room during pre-specified periods of the week, leading to significant energy being wasted as rooms are over-conditioned compared to the actual requirements of the occupants. Though critical, our understanding of occupancy patterns and thermal comfort needs of the occupants in commercial buildings is lacking and it is well known that both of these quantities are stochastic and time-varying, thus requiring sensing solutions to estimate them. This project had the goal of designing, implementing and evaluating a hardware and software solution to ameliorate this challenge. In particular, a depth camera (one whose pixels reveal distance from the camera as opposed to color values) placed on doorways is used to detect entrance and exit events from thermal zones in the building, and thereby estimate their occupancy levels. This information is then fed to a novel control algorithm that can, through interactions with the HVAC system, learn how to provide control inputs that maximize comfort and minimize energy waste. The resulting system represents a significant improvement over existing controllers for commercial HVAC systems and allowed us to improve our understanding of the design of future human-in-the-loop control solutions. For this solution to be feasible, the project had target metrics for its performance and cost. In particular, entrance and exit events for occupants moving about the building would need to be detected with an accuracy higher than 97%; and the resulting control inputs derived from this information would need to lead to approximately 10% energy savings compared to a schedule-based controller. Furthermore, regarding the final hardware design, the project had a target bill of materials (BOM) cost for the sensing solution of less than US$200 per unit while using less than 25W of power on average. All of these target metrics were met or exceeded by our final proposed solution. We performed evaluations by deploying the system in over 20 rooms of different types across 6 commercial buildings in Pittsburgh, PA over the course of three years, and performing targeted controlled experiments to test its performance along the different metrics. The human-in-the-loop control solutions (both hardware and software) developed through this project are expected to lead to significant improvements in the comfort and energy efficiency of HVAC systems used in commercial buildings. The insights we developed through the project pave the way to HVAC systems that can condition interior spaces according to their real-time utilization and the thermal comfort needs of the occupants, thereby reducing energy use. They also open up a new learning-based way of configuring HVAC controllers without having to manually fine-tune them for each building. These innovations can significantly increase the adoption of novel control solutions by the industry and thereby save resources and reduce costs of operation.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2016

Portfolio-Scale Optimization of Customer Energy Efficiency Incentive and Marketing: Cooperative Research and Development Final Report, CRADA Number CRD-13-535

North East utility National Grid (NGrid) is developing a portfolio-scale application of OpenStudio designed to optimize incentive and marketing expenditures for their energy efficiency (EE) programs. NGrid wishes to leverage a combination of geographic information systems (GIS), public records, customer data, and content from the Building Component Library (BCL) to form a JavaScript Object Notation (JSON) input file that is consumed by an OpenStudio-based expert system for automated model generation. A baseline model for each customer building will be automatically tuned using electricity and gas consumption data, and a set of energy conservation measures (ECMs) associated with each NGrid incentive program will be applied to the model. The simulated energy performance and return on investment (ROI) will be compared with customer hurdle rates and available incentives to A) optimize the incentive required to overcome the customer hurdle rate and B) determine if marketing activity associated with the specific ECM is warranted for that particular customer. Repeated across their portfolio, this process will enable NGrid to substantially optimize their marketing and incentive expenditures, targeting those customers that will likely adopt and benefit from specific EE programs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2022

Work Smarter, Not Harder: Improving Energy Efficiency and Safety through Smarter Ventilation: Preprint

Ventilation is a key component to maintaining healthy, safe indoor air quality. Especially important in laboratories, ventilation is the first line of defense against airborne hazards produced during research activities. Though a vital component, laboratory ventilation systems are often victim to ineffective operation, posing a risk to the most important asset - the researchers. Furthermore, system inefficiencies can lead to up to 50% wasted energy. To improve both energy efficiency and safety in laboratories, we present the Smart Labs Toolkit - a resource developed by the U.S. Department of Energy Federal Energy Management Program and the International Institute for Sustainable Laboratories that guides laboratory stakeholders through a straight-forward, holistic approach to achieve dynamic, high-performance laboratories. Smart Labs enable safe and efficient world class science to occur in laboratories through high-performance methods. A Smart Labs program employs a combination of physical, administrative, and management techniques to assess, optimize, and manage high performance laboratories. We will focus on a central component of the Smart Labs approach - the Laboratory Ventilation Risk Assessment, a systematic process for identifying risk due to airborne hazards to inform the operation of dynamic ventilation that optimizes safety and efficiency. Case studies of organizations who have successfully implemented Smart Labs ventilation management programs will also be shared. In learning ventilation strategies successful in critical laboratory environments, learn the tools and resources needed to successfully manage energy in any building through smarter, safer ventilation.

buildings↗
DOE OSTI2014

Optimized Solvent for Energy-Efficient, Environmentally-Friendly Capture of CO{sub 2} at Coal-Fired Power Plants

The overall goal of this project, as originally proposed, was to optimize the formulation of a novel solvent as a critical enabler for the cost-effective, energy-efficient, environmentally-friendly capture of CO{sub 2} at coal-fired utility plants. Aqueous blends of concentrated piperazine (PZ) with other compounds had been shown to exhibit high rates of CO{sub 2} absorption, low regeneration energy, and other desirable performance characteristics during an earlier 5-year development program conducted by B&W. The specific objective of this project was to identify PZ-based solvent formulations that globally optimize the performance of coal-fired power plants equipped with CO{sub 2} scrubbing systems. While previous solvent development studies have tended to focus on energy consumption and absorber size, important issues to be sure, the current work seeks to explore, understand, and optimize solvent formulation across the full gamut of issues related to commercial application of the technology: capital and operating costs, operability, reliability, environmental, health and safety (EH&S), etc. Work on the project was intended to be performed under four budget periods. The objective of the work in the first budget period has been to identify several candidate formulations of a concentrated PZ-based solvent for detailed characterization and evaluation. Work in the second budget period would generate reliable and comprehensive property and performance data for the identified formulations. Work in the third budget period would quantify the expected performance of the selected formulations in a commercial CO{sub 2} scrubbing process. Finally, work in the fourth budget period would provide a final technology feasibility study and a preliminary technology EH&S assessment. Due to other business priorities, however, B&W has requested that this project be terminated at the end of the first budget period. This document therefore serves as the final report for this project. It is the first volume of the two-volume final report and summarizes Budget Period 1 accomplishments under Tasks 1-5 of the project, including the selection of four solvent formulations for further study.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2014

Improving energy efficiency of Embedded DRAM Caches for High-end Computing Systems

With increasing system core-count, the size of last level cache (LLC) has increased and since SRAM consumes high leakage power, power consumption of LLCs is becoming a significant fraction of processor power consumption. To address this, researchers have used embedded DRAM (eDRAM) LLCs which consume low-leakage power. However, eDRAM caches consume a significant amount of energy in the form of refresh energy. In this paper, we propose ESTEEM, an energy saving technique for embedded DRAM caches. ESTEEM uses dynamic cache reconfiguration to turn-off a portion of the cache to save both leakage and refresh energy. It logically divides the cache sets into multiple modules and turns-off possibly different number of ways in each module. Microarchitectural simulations confirm that ESTEEM is effective in improving performance and energy efficiency and provides better results compared to a recently-proposed eDRAM cache energy saving technique, namely Refrint. For single and dual-core simulations, the average saving in memory subsystem (LLC+main memory) on using ESTEEM is 25.8% and 32.6%, respectively and average weighted speedup are 1.09X and 1.22X, respectively. Additional experiments confirm that ESTEEM works well for a wide-range of system parameters.

cache reconfiguration↗
DOE OSTI2024

Energy Efficiency Assistance for Galena Alaska

The City of Galena sits along the north bank of the Yukon River with no road access. Temperatures regularly reach negative 20°F in the winter and sunlight extends for up to 21 hours a day in the summer. Galena’s 400 residents, including members of the Koyukuk Athabascan culture, primarily use fuel oil and locally forested wood for heating and electricity generation. Because these resources are costly to obtain, local households have a high energy burden, spending 7% of their annual income on energy (averaging $4,000 per year). To reduce this burden, the City of Galena joined the U.S. Department of Energy’s (DOE) Remote Alaska Community Energy Efficiency (RACEE) Competition, where they received financial and technical assistance to implement energy savings solutions across their community, including building envelope improvements, solar panels, and LED lighting. Additionally, Galena installed new energy monitoring equipment to continue measuring the impacts of this work beyond the RACEE project.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗