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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 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Integrating Energy-Efficient Computing with Computational Research to Accelerate Energy Technology

NREL's computational sciences center hosts the largest high performance computing (HPC) capabilities dedicated to energy research while functioning as a living laboratory for energy-efficient computing. NREL's HPC capabilities support the research needs of the Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE). In ten years of operation, HPC use in EERE-sponsored research has grown by a factor of 30, including work in electricity generation, energy efficiency, transportation, and energy system modeling. This paper analyzes this research portfolio, providing examples of individual use cases. The paper documents NREL's history of operating one of the world's most energy-efficient data centers while examining pathways to reduce economic and environmental impact beyond reduction of Power Usage Efficiency (PUE). This paper concludes by examining the unique opportunities created for accelerating improvements in data center efficiency created by combining an HPC system dedicated to energy research and a research program in energy-efficient computing.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2012

White Paper on Energy Efficiency Status of Energy-Using Products in China (2012)

2011 is the first year of the 12th Five-Year Plan and, as such, it is a crucial year to push forward the work of energy conservation and emissions reduction. Important large-scale energy conservation policies issued in 2011 include Outline of the 12th Five-year Plan for National Economic and Social Development of The People’s Republic of China (the “Plan”) and Notice of the State Council on Issuing the Comprehensive Work Proposal for Energy Conservation and Emission Reduction during the 12th Five-Year Plan Period (GF (2011) No. 26) (the “Proposal”). These two policies have established strategic objectives for energy conservation during the 12th Five-Year Plan in China, and they have also identified the key tasks and direction of energy efficiency programs for energy-using products.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2015

Energy Efficiency Collaboratives

Collaboratives for energy efficiency have a long and successful history and are currently used, in some form, in more than half of the states. Historically, many state utility commissions have used some form of collaborative group process to resolve complex issues that emerge during a rate proceeding. Rather than debate the issues through the formality of a commission proceeding, disagreeing parties are sent to discuss issues in a less-formal setting and bring back resolutions to the commission. Energy efficiency collaboratives take this concept and apply it specifically to energy efficiency programs—often in anticipation of future issues as opposed to reacting to a present disagreement. Energy efficiency collaboratives can operate long term and can address the full suite of issues associated with designing, implementing, and improving energy efficiency programs. Collaboratives can be useful to gather stakeholder input on changing program budgets and program changes in response to performance or market shifts, as well as to provide continuity while regulators come and go, identify additional energy efficiency opportunities and innovations, assess the role of energy efficiency in new regulatory contexts, and draw on lessons learned and best practices from a diverse group. Details about specific collaboratives in the United States are in the appendix to this guide. Collectively, they demonstrate the value of collaborative stakeholder processes in producing successful energy efficiency programs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2015

Diblock Copolymer Micelles and Supported Films with Noncovalently Incorporated Chromophores: A Modular Platform for Efficient Energy Transfer

Here we report generation of modular, artificial light-harvesting assemblies where an amphiphilic diblock copolymer, poly(ethylene oxide)-block-poly(butadiene), serves as the framework for noncovalent organization of BODIPY-based energy donor and bacteriochlorin-based energy acceptor chromophores. The assemblies are adaptive and form well-defined micelles in aqueous solution and high-quality monolayer and bilayer films on solid supports, with the latter showing greater than 90% energy transfer efficiency. Ultimately, this study lays the groundwork for further development of modular, polymer-based materials for light harvesting and other photonic applications.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Material and Energy Efficiency: A Framework for Broader Analysis of Energy Use in the U.S. Economy

Energy efficiency analysis has focused predominantly on reducing energy at its point of use by individual components, processes, or products. Efforts to address the energy embodied in materials through strategies and technologies that reduce raw material production - while maintaining the function and use of materials - offer a complementary and expansive approach to traditional energy efficiency analysis. The U.S. Department of Energy (DOE) energy analysis community currently lacks analytical tools that are appropriate for 1) estimating on a product and economy-wide basis energy efficiency potential achieved through material efficiency strategies and 2) evaluating how these new strategies may complement existing energy efficiency efforts. The goal of this report is to describe a standardized analysis framework that would enable calculation of embodied and direct energy and the estimation of energy reduction potential achieved through changes in material use. The proposed framework meets this functionality by spanning the entire U.S. economy, including international trade flows; capturing material and energy use in products and services from raw material extraction to retirement; maintaining material and energy balances; and adjusting dynamically to absolute and relative changes in materials and energy use. The framework is composed of two main elements: a dynamic hybrid input-output (IO) model and a material energy identity. The hybrid IO model defines recipes for material and energy flows in physical (e.g., British thermal units [Btus] and tons) and monetary units, and allows for dynamic adjustments to the amount of materials and energy used. The second element of the analytical framework, the material energy identity, acts as a way of identifying and organizing energy and material efficiency strategies, which are then implemented and analyzed in the hybrid IO model. The report also provides a simple example application of the proposed framework, which illustrates the concept of reducing energy use through changes to material efficiency.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2015

DEEP: A Database of Energy Efficiency Performance to Accelerate Energy Retrofitting of Commercial Buildings

The paper presents a method and process to establish a database of energy efficiency performance (DEEP) to enable quick and accurate assessment of energy retrofit of commercial buildings. DEEP was compiled from results of about 35 million EnergyPlus simulations. DEEP provides energy savings for screening and evaluation of retrofit measures targeting the small and medium-sized office and retail buildings in California. The prototype building models are developed for a comprehensive assessment of building energy performance based on DOE commercial reference buildings and the California DEER prototype buildings. The prototype buildings represent seven building types across six vintages of constructions and 16 California climate zones. DEEP uses these prototypes to evaluate energy performance of about 100 energy conservation measures covering envelope, lighting, heating, ventilation, air-conditioning, plug-loads, and domestic hot water. DEEP consists the energy simulation results for individual retrofit measures as well as packages of measures to consider interactive effects between multiple measures. The large scale EnergyPlus simulations are being conducted on the super computers at the National Energy Research Scientific Computing Center of Lawrence Berkeley National Laboratory. The pre-simulation database is a part of an on-going project to develop a web-based retrofit toolkit for small and medium-sized commercial buildings in California, which provides real-time energy retrofit feedback by querying DEEP with recommended measures, estimated energy savings and financial payback period based on users’ decision criteria of maximizing energy savings, energy cost savings, carbon reduction, or payback of investment. The pre-simulated database and associated comprehensive measure analysis enhances the ability to performance assessments of retrofits to reduce energy use for small and medium buildings and business owners who typically do not have resources to conduct costly building energy audit. DEEP will be migrated into the DEnCity - DOE’s Energy City, which integrates large-scale energy data for multi-purpose, open, and dynamic database leveraging diverse source of existing simulation data.

Hoon Lee, Sang↗
DOE OSTI2023

Experimental and theoretical investigations of rotating algae biofilm reactors (RABRs): Areal productivity, nutrient recovery, and energy efficiency

Microalgae biofilms have been demonstrated to recover nutrients from wastewater and serve as biomass feedstock for bioproducts. However, there is a need to develop a platform to quantitatively describe microalgae biofilm production, which can provide guidance and insights for improving biomass areal productivity and nutrient uptake efficiency. Here, this paper proposes a unified experimental and theoretical framework to investigate algae biofilm growth on a rotating algae biofilm reactor (RABR). Experimental laboratory setups are used to conduct controlled experiments on testing environmental and operational factors for RABRs. We propose a differential–integral equation‐based mathematical model for microalgae biofilm cultivation guided by laboratory experimental findings. The predictive mathematical model development is coordinated with laboratory experiments of biofilm areal productivity associated with ammonia and inorganic phosphorus uptake by RABRs. The unified experimental and theoretical tool is used to investigate the effects of RABR rotating velocity, duty cycle (DC), and light intensity on algae biofilm growth, areal productivity, nutrient uptake efficiency, and energy efficiency in wastewater treatment. Our framework indicates that maintaining a reasonable light intensity range improves biomass areal productivity and nutrient uptake efficiency. Our framework also indicates that faster RABR rotation benefits biomass areal productivity. However, maximizing the nutrient uptake efficiency requires a reasonably low RABR rotating speed. Energy efficiency is strongly correlated with RABR rotating speed and DC.

09 BIOMASS FUELS↗
DOE OSTI2013

Group Home Energy Efficiency Retrofit for 30% Energy Savings: Washington, D.C. (Fact Sheet)

Energy efficiency retrofits (EERs) face many challenges on the path to scalability. Limited budgets, cost effectiveness, risk factors, and accessibility impact the type and the extent of measures that can be implemented feasibly to achieve energy savings goals. Group home retrofits can face additional challenges than those in single family homes - such as reduced access (occupant-in-place restrictions) and lack of incentives for occupant behavioral change. This project studies the specification, implementation, and energy savings from an EER in a group home, with an energy savings goal of 30%. This short term test report chronicles the retrofit measures specified, their projected cost-effectiveness using building energy simulations, and the short term test results that were used to characterize pre-retrofit and post-retrofit conditions. Additionally, the final report for the project will include analysis of pre- and post-retrofit performance data on whole building energy use, and an assessment of the energy impact of occupant interface with the building (i.e., window operation). Ultimately, the study's results will be used to identify cost effective EER measures that can be implemented in group homes, given constraints that are characteristic of these buildings. Results will also point towards opportunities for future energy savings.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2013

Existing Whole-House Solutions Case Study: Group Home Energy Efficiency Retrofit for 30% Energy Savings, Washington, D.C.

Energy efficiency retrofits (EERs) face many challenges on the path to scalability. Limited budgets, cost effectiveness, risk factors, and accessibility impact the type and the extent of measures that can be implemented feasibly to achieve energy savings goals. Group home retrofits can face additional challenges than those in single family homes – such as reduced access (occupant-in-place restrictions) and lack of incentives for occupant behavioral change. This project studies the specification, implementation, and energy savings from an EER in a group home, with an energy savings goal of 30%. This short term test report chronicles the retrofit measures specified, their projected cost-effectiveness using building energy simulations, and the short term test results that were used to characterize pre-retrofit and post-retrofit conditions. Additionally, the final report for the project will include analysis of pre- and post-retrofit performance data on whole building energy use, and an assessment of the energy impact of occupant interface with the building (i.e., window operation). Ultimately, the study’s results will be used to identify cost effective EER measures that can be implemented in group homes, given constraints that are characteristic of these buildings. Results will also point towards opportunities for future energy savings.

BA-PIRC↗
DOE OSTI2014

Residential Energy Efficiency Demonstration: Hawaii and Guam Energy Improvement Technology Demonstration Project

In order to meet its energy goals, the Department of Defense (DOD) has partnered with the Department of Energy (DOE) to rapidly demonstrate and deploy cost-effective renewable energy and energy-efficiency technologies. The scope of this project was to demonstrate tools and technologies to reduce energy use in military housing, with particular emphasis on measuring and reducing loads related to consumer electronics (commonly referred to as 'plug loads'), hot water, and whole-house cooling.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2025

Providence Performing Arts Center (PPAC): Energy Efficient Upgrades

The Energy Efficient Upgrades project at the Providence Performing Arts Center represents a significant investment in modernizing infrastructure, enhancing performance capabilities and improving visitor experience, all while promoting sustainability. The project’s primary goals included the installation of building-wide WIFI coverage, replacement of the outdated theatrical lighting system with energy-efficient alternatives, upgrades to the telephone systems and enhancements to the internal sound systems, both backstage and in the lobby.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2014

Assessing National Employment Impacts of Investment in Residential and Commercial Sector Energy Efficiency: Review and Example Analysis

Energy efficiency is a key solution to concerns regarding future energy supply, energy security, and the harmful long-term effects of climate change. In addition to addressing these issues, actions motivated by governmental policies and programs, along with efforts by utilities and third parties, result in greater energy efficiency and also save consumers money. A continuing question is the degree to which energy efficiency measures spur economic growth and higher levels of employment. Research interest in this topic has recently risen in response to trends reflecting increased market adoption of energy efficiency measures, increased reliance on energy efficiency as a resource to offset new electricity generation, and the utilization of energy efficiency portfolio standards by states to spur wider adoption of energy efficiency and reduce future electricity demand.

Economic Impact Modeling↗
DOE OSTI2022

Route Optimization for Energy Efficient Airport Shuttle Operations - A Case Study from Dallas Fort Worth International Airport

Air travel and requisite surface traffic supporting passenger arrival/departure constitutes a significant portion of travel and emissions in cities with large airports. An airport trip can segment into three parts namely: i) travel from a location in the city to the airport; ii) travel from a parking lot or rental car center to the terminal (i.e., within the airport premises), and iii) travel inside the terminal. Depending on the airport access mode all or a part of these legs comprise a traveler’s journey to the airport. The priority of airport ground transport management teams is to provide passengers with a seamless travel experience within the airport, so it is understandable that within airport shuttle routes might not be optimized for minimizing energy consumption. Solutions that meet the dual objective of reducing energy consumption from airport shuttle operations without compromising on passenger travel experience are key to improving system efficiency. There is currently a dearth of research and tools that can inform airports in making such decisions. Addressing this need, this research effort puts forth an optimization model that generates optimal shuttle routes for a given set of constraints, and a discrete-event simulator that evaluates the optimal solutions in a stochastic environment to understand the tradeoffs between passenger wait times, and within airport shuttle energy consumption. The proposed set of tools are tested in the context of optimizing airport shuttles routes within the Dallas Fort Worth International Airport (DFW). In addition to shuttle spatial positioning, and passenger demand information, high-fidelity vehicle data was collected using data loggers installed on DFW shuttles. Results show that 20% energy reduction in shuttle operations is possible with a modest two-minute increase in average passenger wait times. The tools developed in this research effort are designed to be generalizable and can help optimize shuttle operations planning at any major airport.

air travel↗
DOE OSTI2012

Sustainable energy for all. Technical report of task force 2 in support of doubling the global rate of energy efficiency improvement and doubling the share of renewable energy in the global energy mix by 2030

The UN Secretary General established the Sustainable Energy for All initiative in order to guide and support efforts to achieve universal access to modern energy, rapidly increase energy efficiency, and expand the use of renewable energies. Task forces were formed involving prominent energy leaders and experts from business, government, academia and civil society worldwide. The goal of the Task Forces is to inform the implementation of the initiative by identifying challenges and opportunities for achieving its objectives. This report contains the findings of Task Force Two which is dedicated energy efficiency and renewable energy objectives. The report shows that doubling the rate of energy efficiency improvements and doubling the share of energy from renewable sources by 2030 is challenging but feasible if sufficient actions are implemented. Strong and well-informed government policies as well as extensive private investment should focus on the high impact areas identified by the task force.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗