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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 199 records · Page 11
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Beyond Energy Efficiency: A clustering approach to embed demand flexibility into building energy benchmarking

The intermittency of carbon-free renewables and the demand changes associated with the widespread push for electrifying the transportation and building sectors provides an opportunity for buildings to go beyond energy efficiency and push towards providing demand flexibility to the electricity grid. The duality of energy efficiency and demand flexibility is necessary for success in a sustainable and reliable energy transition. Current building energy benchmarking models are limited in their ability to integrate concepts of demand flexibility and/or utilize granular smart meter data. Thus, current benchmarking methods are focused annual energy usage and fail to incorporate how the time of use of energy consumption impacts emissions in a quickly changing energy grid. Without a more comprehensive view of energy usage and associated real-time emissions, current benchmarking methods are unlikely to realize the full decarbonization potential of buildings. New emerging data streams provide an opportunity to develop a new generation of benchmarking energy models that embed dimensions of energy efficiency, grid interactivity, and demand flexibility into their analysis. In this paper, we propose a four-step method for embedding grid interactivity and demand flexibility into building benchmarking models that utilizes emerging building and time-series electricity data streams. We first engineer features to produce a mix-type dataset that encompasses many attributes of grid-interactive and efficient buildings, and then we apply K-medoids using Gower's Distance to produce peer-group clusters. We apply the method to a case study of 306 primary and secondary schools in southern California, USA. The results show that the method effectively clusters buildings by attributes of demand flexibility and energy efficiency. The clustering results reveal patterns in inefficient building operations and demand inflexibility at the building peer group level. In conclusion, the interpretation of clusters can serve as an integrated energy efficiency and demand flexibility benchmarking model and inform performance-specific policy targeting for buildings that go beyond traditional efficiency measures.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2018

Achieving Regional Energy Efficiency Potential in the Midwest

The Midwest Energy Efficiency Alliance report on actions to accelerate adoption of energy efficiency in the Midwest through regional collaborations with state and local governments, utilities, industry, environmental and consumer groups and other stakeholders in a 13 state region (IA, IL, IN, KS, KY, MI, MN, MO, NE, ND, OH, SD and WI). MEEA collaborated with multiple Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EE) programs, including the Buildings Technologies Program (BTP), Office of Strategic Programs (OSP), Weatherization and Intergovernmental Programs (WIP), and Advanced Manufacturing Office (AMO) to further energy efficiency efforts in the Midwest. In addition, MEEA collaborated with other Regional Energy Efficiency Organizations (REEOs) such as the Northwest, Northeast, Southwest and Southeast REEOs. Such alignment among all REEOs and with DOE sought to build increased workforce capacities nationwide to design, plan, deliver and verify energy efficiency solutions and make individual REEOs more successful in reaching their objectives. The proposed work accelerated deployment of DOE initiatives in local and regional markets, as well as coordinated the activities of each REEO for the dissemination of best practices.

03 NATURAL GAS↗
DOE OSTI2018

Improving Ukraine’s Energy Security: the Role of Energy Efficiency

This report analyzes the link between energy security and energy efficiency in Ukraine. The paper explores the roots of high energy intensity of the Ukrainian economy and its dependence on imported energy resources. In recent years, the Government of Ukraine has linked energy security with energy efficiency, which indicates a paradigm shift in the country’s energy strategy. Using broad statistical data, the report explores the major options for Ukraine in improving its energy efficiency. Special attention is paid to energy consumption in the residential sector and district heating. The report analyzes recent economic, legislative, and institutional measures to promote energy efficiency and strengthen energy security. The analysis shows that Ukraine can significantly reduce its dependence on imported energy resources and avoid major energy security risks by creating an enabling environment for large-scale energy efficiency improvements in all sectors of the Ukrainian economy.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2010

Efficient energy conversion from laser to proton beam in a laser-foil interaction

Demonstrated is a remarkable improvement on the energy conversion efficiency from laser to protons in a laser-foil interaction by particle simulations. The total laser-proton energy conversion efficiency becomes 16.7%, although a conventional plane foil target serves a rather low efficiency. In our previous study we found that Al multihole thin-foil target was efficient for the energy conversion from laser to protons [Y. Nodera and S. Kawata, Phys. Rev. E 78, 046401 (2008)], and the energy conversion efficiency was 9.3%. In our 2.5-dimensional particle-in-cell simulations the Al multihole structure is also employed, and the parameters of the Al multihole wing width and length are optimized in the paper. The present results clarify the roles of the target Al hole width and depth in the laser-proton energy conversion. The main physical reason for the enhancement of the conversion efficiency is a reduction of the laser reflection at the target surface area. The optimized multihole foil target provides a remarkable increase in the laser-proton energy conversion efficiency as shown above.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2014

Sustainable Transportation: Accelerating Widespread Adoption of Energy Efficient Vehicles & Fuels (Brochure)

While energy efficient transportation strategies have the potential to simultaneously slash oil consumption and reduce greenhouse gas (GHG) emissions, a truly sustainable solution will require more than just putting drivers behind the wheels of new fuel-efficient cars. As the only national laboratory dedicated 100% to renewable energy and energy efficiency, the National Renewable Energy Laboratory (NREL) accelerates widespread adoption of high-performance, low-emission, energy-efficient passenger and freight vehicles, as well as alternative fuels and related infrastructure. Researchers collaborate closely with industry, government, and research partners, using a whole-systems approach to design better batteries, drivetrains, and engines, as well as thermal management, energy storage, power electronic, climate control, alternative fuel, combustion, and emission systems. NREL's sustainable transportation research, development, and deployment (RD&D) efforts are not limited to vehicles, roads, and fueling stations. The lab also explores ways to save energy and reduce GHGs by integrating transportation technology advancements with renewable energy generation, power grids and building systems, urban planning and policy, and fleet operations.

25 ENERGY STORAGE↗
DOE OSTI2019

Multiple Benefits of Industrial Energy Efficiency – Lessons Learned and New Initiatives

Past research has shown that energy efficiency implementation in manufacturing can yield additional, quantifiable benefits in areas such as maintenance, production and environmental performance. However, these types of benefits don’t often get identified or estimated during energy efficiency assessments on industrial plants or systems. In addition, these types of benefits are often omitted from conventional performance metrics, leading to overly modest payback calculations and an imperfect understanding of the impact of energy efficiency in manufacturing. If the non-energy related or multiple benefits of energy efficiency measures were to be estimated with good certainty in industrial energy assessments, the true magnitude of energy efficiency measures could be understood, leading to better and more accurate return on investment estimates for energy efficiency projects. According to the IEA report “Capturing the Multiple Benefits of Energy Efficiency (2014),” the monetary value of non-energy benefits stemming from industrial energy efficiency implementation could be in the range of 40% to 50% of the value of energy savings per measure, which could lower energy-efficiency project paybacks by more than half. In order to integrate the potential multiple benefits of energy-efficiency investments in energy efficiency assessments, these benefits need to be identified and quantified during energy efficiency assessments. To help achieve this an effort is underway to develop a training platform to enable companies and individuals who perform energy assessments to include multiple benefits of energy efficiency in project evaluations. This platform will include tools to analyze energy-saving projects, training workshops, and communications techniques and materials to provide the knowledge base to effectively integrate multiple benefits in the investment evaluations of energy efficiency measures. By integrating multiple benefit analyses in the energy assessments and assessment reports it is expected that the business case for energy efficiency will be bolstered leading to greater implementation of energy efficiency projects in manufacturing. This paper will discuss previous research showing the multiple benefits of energy efficiency in manufacturing and the analytical and communications framework that will enable the integration of multiple benefits in energy efficiency assessments.

Lung, Bruce↗
DOE OSTI2022

The impact of energy-efficiency upgrades and other distributed energy resources on a residential neighborhood-scale electrification retrofit

We report ambitious targets for carbon emissions reductions are highlighting new challenges for electrification strategies, leading to an increased focus on building load flexibility and energy management to complement the variability inherent in renewable energy generation. Over the next decade millions of existing homes could undergo electrification retrofits, and there is an urgent need to understand the potential impacts of electrifying major residential loads such as water and space heating on community load characteristics, resident energy bills, and the utility's distribution system. Behind-the-meter distributed energy resources (DERs), including efficiency measures, photovoltaics (PV), battery storage, managed electric vehicle (EV) charging, and controls such as home energy management systems (HEMS), can significantly alter a neighborhood's load profile and provide benefits to both the residents and the grid. We present a novel approach to characterizing the impact of a hypothetical neighborhood-scale residential retrofit program on individual homes' energy use profiles, associated utility bills, and the local distribution system. We modeled a mixed-fuel community of 30 single-family homes in Denver, Colorado, and compared the effects of retrofit scenarios ranging from conventional energy-efficiency upgrades to full electrification with and without more advanced DER technologies. We analyzed which packages of DERs most reliably enable demand flexibility in response to a time-of-use (TOU) rate for this and similar neighborhoods. Our buildings-to-grid co-simulation framework includes a generic secondary distribution feeder model to capture voltage profiles, transformer loading, and other grid impacts in each case. We also calculated the carbon emissions associated with energy use in the community. The methodology developed here can be broadly applied to community-scale beneficial electrification studies in other regions, climates, utility infrastructures, and building typologies to make specific, targeted recommendations based on quantified projections of energy demand in any given community. Our findings indicate that residential electrification can be achieved without negatively impacting the monthly utility bill, and that a combination of conventional energy-efficiency measures, PV, battery, controls, and managed EV charging to maximize a community's demand flexibility is a promising strategy. Adding DERs (especially PV) as part of efficient electrification produces much bigger savings than efficient electrification without DERs. A key barrier is that upgrades require upfront costs, and modest utility bill savings result in long payback periods.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2014

Note: High-efficiency energy harvester using double-clamped piezoelectric beams

In this study, an improvement in energy conversion efficiency has been reported, which is realized by using a double-clamped piezoelectric beam, based on uniaxial stretching strain. The buckling mechanism is applied to maximize axial stress in the double-clamped beam. The voltage generated by using the double-clamped piezoelectric beam is higher than that generated by using other conventional structures, such as bending cantilevers coated/sandwiched with piezoelectric film, which is proven both theoretically and experimentally. The power generation efficiency is enhanced by further optimizing the double-clamped structure. The optimized high-efficiency energy harvester utilizing double-clamped piezoelectric beams generates a peak output power of 80 μW, under an acceleration of 0.1g.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2023

Energy-recovery linacs for energy-efficient particle acceleration

Energy Recovery Linacs (ERLs) are inherently energy-efficient because the RF power needed for acceleration is recovered during deceleration. Energy recovery enables extremely high-power beams which are not economically or ecologically possible using a simple Linac. The fundamental technology is not new but has taken on an increased importance in recent years. Here in this Review, I describe the positive aspects of the technology, the areas that are under active study to improve the overall efficiency, and areas that still need further R&D. The need for validation of the entire system will be explained and the active proposals described.

43 PARTICLE ACCELERATORS↗
DOE OSTI2021

Techno-Economic Impact Assessments of Energy Efficiency Improvements in the Industrial Combustion Systems

Industrial energy efficiency assessments not only provide benefits to manufacturers but also generate significant economic and environmental benefits to localities, states, and the nation through indirect and induced benefits. Quantifying these benefits requires a systematic economic framework for capturing these interactions. This article employs methodologies for improving the energy efficiency of small- and medium-sized industry through their combustion systems. Combustion systems offer large opportunities to enhance energy efficiency through adopting advanced technologies and better-informed operations. The case studies presented illuminate the potential savings and impacts from implementing energy-efficient combustion recommendations and the importance of energy audits and energy efficiency in the fight against climate change. This study describes and quantifies the cascading economic and environmental impacts of implementing the industrial energy efficiency recommendations offered by an energy auditing program by participating facilities over a 10-year period. Results showed that it is expected that a total of $185 M would be saved in energy costs, and 2.3 million metric tons of carbon dioxide emissions would be avoided annually, and about 972 jobs could be created in the studied region if all the combustion recommendations would be implemented. Furthermore, the broader view afforded by the proposed study can be used to support better energy-efficient practices in manufacturing facilities, communities, and states.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2010

Energy Efficiency Improvement and Cost Saving Opportunities for the U.S. Iron and Steel Industry An ENERGY STAR(R) Guide for Energy and Plant Managers

Energy is an important cost factor in the U.S iron and steel industry. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. iron and steel industry to reduce energy consumption in a cost-effective manner. This Energy Guide discusses energy efficiency practices and energy-efficient technologies that can be implemented at the component, process, facility, and organizational levels. A discussion of the structure, production trends, energy consumption, and greenhouse gas emissions of the iron and steel industry is provided along with a description of the major process technologies used within the industry. Next, a wide variety of energy efficiency measures are described. Many measure descriptions include expected savings in energy and energy-related costs, based on case study data from real-world applications in the steel and related industries worldwide. Typical measure payback periods and references to further information in the technical literature are also provided, when available. The information in this Energy Guide is intended to help energy and plant managers in the U.S. iron and steel industry reduce energy consumption and greenhouse gas emissions in a cost-effective manner while maintaining the quality of products manufactured. Further research on the economics of all measures?and on their applicability to different production practices?is needed to assess their cost effectiveness at individual plants.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2019

Powering Energy Efficiency and Impacts: Mapping a Comprehensive Regional Energy Strategy for Upper Coastal Plain Council of Government Region

The Powering Energy Efficiency and Impacts Framework (PEEIF) project, a two-year U.S. Department of Energy (DOE) sponsored initiative, seeks to develop a data-driven framework to increase energy-related program effectiveness in low-income households. As part of this project, a diverse, multi-sector partnership developed a database and a geospatial-mapping tool of homes located in five eastern North Carolina counties served by the Upper Coastal Plain Council of Governments (UCPCOG), the lead administrator for the effort. This report outlines the needs, challenges, and solutions identified through the project and presents opportunities for state agencies, utilities, and organizations that are currently providing, or interested in supporting, low income energy-efficiency services. It details the project's methods and results and identifies strategies for future iterations of the mapping tool

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2022

Nanoparticle-enabled increase of energy efficiency during laser metal additive manufacturing

The low energy efficiency of the laser metal additive manufacturing (AM) process is a potential sustainability concern for large-scale industrial production. Explicit investigation of the energy efficiency for laser melting requires the direct characterization of melt pool dimension and vapor depression, which is very difficult due to the opaque nature of the molten metal. Here we report the direct observation and quantification of effects of the TiC nanoparticles on the vapor depression and melt pool formation during laser powder bed fusion (LPBF) of Al6061 by in-situ high-speed high-energy x-ray imaging. Based on the quantification results, we calculated the laser melting energy efficiency (defined here as the ratio of the energy needed to melt the material to the energy delivered by the laser beam) with and without TiC nanoparticles during LPBF of Al6061. Here the results show that adding TiC nanoparticles into Al6061 leads to a significant increase of laser melting energy efficiency (114% increase on average, 521% increase under 312 W laser power, 0.4 m/s scan speed). Systematic property measurement, simulation, and x-ray imaging studies enable us, for the first time, to identify that three mechanisms work together to enhance the laser melting energy efficiency: (1) adding TiC nanoparticles increases the absorptivity; (2) adding TiC nanoparticles decreases the thermal conductivity, and (3) adding TiC nanoparticles enables the initiation of vapor depression and multiple reflection at lower laser power (i.e., lowers the laser power threshold for keyholing). The method and mechanisms of using TiC nanoparticles to increase the laser melting energy efficiency during LPBF of Al6061 we reported here may guide the development of feedstock materials for more energy efficient laser metal AM.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Energy Efficient Data Centers

Energy efficient data center strategies include thermal/environmental guidelines, air management, free cooling, and liquid-based cooling. A case study highlighting the data center cooling system at the National Renewable Energy Laboratory Energy Systems Integration Facility illustrates many of these principles.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Energy Efficient Data Centers

Energy efficient data center strategies include thermal/environmental guidelines, air management, free cooling, and liquid-based cooling. A case study highlighting the data center cooling system at the National Renewable Energy Laboratory Energy Systems Integration Facility illustrates many of these principles.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Chapter 4: Small Commercial and Residential Unitary and Split System HVAC Heating and Cooling Equipment-Efficiency Upgrade Evaluation Protocol. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures

The specific measure described here involves improving the overall efficiency in air-conditioning systems as a whole (compressor, evaporator, condenser, and supply fan). The efficiency rating is expressed as the energy efficiency ratio (EER), seasonal energy efficiency ratio (SEER), and integrated energy efficiency ratio (IEER). The higher the EER, SEER or IEER, the more efficient the unit is.

24 POWER TRANSMISSION AND DISTRIBUTION↗