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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 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Investigating power capping toward energy-efficient scientific applications: Investigating Power Capping toward Energy-Efficient Scientific Applications

The emergence of power efficiency as a primary constraint in processor and system design poses new challenges concerning power and energy awareness for numerical libraries and scientific applications. Power consumption also plays a major role in the design of data centers, which may house petascale or exascale-level computing systems. At these extreme scales, understanding and improving the energy efficiency of numerical libraries and their related applications becomes a crucial part of the successful implementation and operation of the computing system. In this paper, we study and investigate the practice of controlling a compute system's power usage, and we explore how different power caps affect the performance of numerical algorithms with different computational intensities. Further, we determine the impact, in terms of performance and energy usage, that these caps have on a system running scientific applications. This analysis will enable us to characterize the types of algorithms that benefit most from these power management schemes. Our experiments are performed using a set of representative kernels and several popular scientific benchmarks. Lastly, we quantify a number of power and performance measurements and draw observations and conclusions that can be viewed as a roadmap to achieving energy efficiency in the design and execution of scientific algorithms.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2022

REopt for Resilient Buildings: Leveraging Energy Efficiency and Distributed Energy Resources for Resilience Solutions

Community resilience hubs are locally identified and community-serving facilities that provide residents year-round access to support resources. During extreme weather, they can reduce the burden on emergency response teams by supplying power before, during, and after grid outages through onsite energy systems. This presentation analyzes how NREL's REopt tool can leverage energy efficiency, distributed generation, and storage resources to ensure critical community facilities are online when they are needed most. We showcase the tool's capabilities and application through a case study that focuses on achieving resilience for critical facilities in Manatee County.

better buildings↗
DOE OSTI2013

Sault Tribe Building Efficiency Energy Audits

The Sault Ste. Marie Tribe of Chippewa Indians is working to reduce energy consumption and expense in Tribally-owned governmental buildings. The Sault Ste. Marie Tribe of Chippewa Indians will conduct energy audits of nine Tribally-owned governmental buildings in three counties in the Upper Peninsula of Michigan to provide a basis for evaluating and selecting the technical and economic viability of energy efficiency improvement options. The Sault Ste. Marie Tribe of Chippewa Indians will follow established Tribal procurement policies and procedures to secure the services of a qualified provider to conduct energy audits of nine designated buildings. The contracted provider will be required to provide a progress schedule to the Tribe prior to commencing the project and submit an updated schedule with their monthly billings. Findings and analysis reports will be required for buildings as completed, and a complete Energy Audit Summary Report will be required to be submitted with the provider?s final billing. Conducting energy audits of the nine governmental buildings will disclose building inefficiencies to prioritize and address, resulting in reduced energy consumption and expense. These savings will allow Tribal resources to be reallocated to direct services, which will benefit Tribal members and families.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2013

Strategies for Energy-Efficient Resource Management of Hybrid Programming Models

Many scientific applications are programmed using hybrid programming models that use both message passing and shared memory, due to the increasing prevalence of large-scale systems with multicore, multisocket nodes. Previous work has shown that energy efficiency can be improved using software-controlled execution schemes that consider both the programming model and the power-aware execution capabilities of the system. However, such approaches have focused on identifying optimal resource utilization for one programming model, either shared memory or message passing, in isolation. The potential solution space, thus the challenge, increases substantially when optimizing hybrid models since the possible resource configurations increase exponentially. Nonetheless, with the accelerating adoption of hybrid programming models, we increasingly need improved energy efficiency in hybrid parallel applications on large-scale systems. In this work, we present new software-controlled execution schemes that consider the effects of dynamic concurrency throttling (DCT) and dynamic voltage and frequency scaling (DVFS) in the context of hybrid programming models. Specifically, we present predictive models and novel algorithms based on statistical analysis that anticipate application power and time requirements under different concurrency and frequency configurations. Furthermore, we apply our models and methods to the NPB MZ benchmarks and selected applications from the ASC Sequoia codes. Overall, we achieve substantial energy savings (8.74 percent on average and up to 13.8 percent) with some performance gain (up to 7.5 percent) or negligible performance loss.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2022

Analyzing the Multiscale Impacts of Implementing Energy-Efficient HVAC Improvements Through Energy Audits and Economic Input–Output Analysis

Abstract Heating, ventilation, and air-conditioning (HVAC) systems are usually an industry’s highest consumer of energy, most of which goes toward space cooling in buildings. Industrial energy-efficiency audits not only benefit manufacturers but also generate significant economic and environmental benefits to localities, states, and the nation. This article analyzes the micro- and macro scale impacts of implementing energy-efficient HVAC systems by integrating the industrial building energy data with the macroeconomic regional economic flow model. Micro-scale data include 10 years of historical energy, cost, and carbon dioxide savings achieved from energy-efficient HVAC implementation offered to manufacturers through industrial energy audits. The data were integrated into the macroeconomic modeling framework to illuminate the cascading regional economic impacts of implementing energy-efficient HVAC recommendations in manufacturing facilities. Results show that if recommendations had been implemented throughout all manufacturers in the region, $656 M energy costs would have been directly saved, 7.8 million metric tons of carbon dioxide emissions would have been avoided, and 4387 jobs could have been created, resulting in a total annual economic impact of $899 M stemming from direct, indirect, and induced impacts. The results offer insight into how industrial energy systems can be designed and provide models for how communities can accomplish a net-zero society.

Energy & Fuels↗
DOE OSTI2021

Deferred Payment Loans for Energy Efficiency: Case Study of a Low- and Moderate-Income Home Improvement Financing Model and Potential Application to Energy Efficiency Projects

Energy efficiency can provide important benefits for low- and moderate-income households such as lower utility bills and healthier, more comfortable homes, but the upfront costs of efficiency improvements are often a barrier. Extending financing to these households can help overcome this barrier but presents its own challenges, including the financial burden of monthly payments and the risk of incurring the repercussions of nonpayment. The deferred payment loan model can give low- and moderate-income households access to energy efficiency without the financial burden of monthly payments while mitigating the risk of nonpayment. From a program sponsor perspective, when grant funds are limited or unavailable, the model provides certain advantages of both grants and financing. Like a grant, target recipients have minimal risk, but like a loan, funds can serve multiple participants since the funding can be revolved. Organizations in several parts of the country have employed the model to provide safe, healthy homes by paying for home repair and home improvement. This case study provides a detailed overview of the deferred payment loan program for home improvements known as the Home Repair Program run by the Opportunity Council, a Community Action Agency (CAA) serving three counties in Washington State. This case study also considers two other CAA-administered deferred payment loan programs – one in Wisconsin and another in Michigan.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2015

Building America Case Study: Northwest Energy Efficient Manufactured Housing Program High-Performance Test Homes; Whole-House Solutions for New Homes, Energy Efficiency & Renewable Energy (EERE)

?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. 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↗
NASA NTRS1977

Air transportation energy efficiency

The energy efficiency of air transportation, results of the recently completed RECAT studies on improvement alternatives, and the NASA Aircraft Energy Efficiency Research Program to develop the technology for significant improvements in future aircraft were reviewed.

Williams, L. J.↗
DOE OSTI2015

White Paper: Unleashing Energy Efficiency Retrofits Through Energy Performance Contracts in China and the United States

Energy performance contracting (EPC) is a mechanism that uses private sector investment and expertise to deploy energy efficiency retrofits in buildings, industries, and other types of facilities. China and the United States both have large, growing EPC markets. This White Paper shares key insights on each market, including strengths and barriers inherent to these markets, compares the two markets, and sets forth options for enhancing EPC markets in each country. The White Paper concludes with recommendations structured around common goals of both countries.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2024

Medical Imaging Equipment Energy Efficiency

The energy use of medical imaging equipment (MIE) in healthcare facilities is estimated to be about 5% of total site energy use. MIE energy use is only expected to increase as technology advances and more patients seek services from MIE, enabling more facilities to install additional MIE. Healthcare organizations need reliable information regarding comprehensive energy use or lifetime energy costs with which to make energy-efficient MIE procurement decisions, and there are currently no MIE energy or efficiency standards in the United States (U.S.). This fact sheet provides background on MIE energy consumption, key terms, and guidance on why and how to meter MIE, helping stakeholders make informed decisions to enhance their facility's performance.

ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION↗
DOE OSTI2015

Using learning curves on energy-efficient technologies to estimate future energy savings and emission reduction potentials in the U.S. iron and steel industry

Increasing concerns on non-sustainable energy use and climate change spur a growing research interest in energy efficiency potentials in various critical areas such as industrial production. This paper focuses on learning curve aspects of energy efficiency measures in the U.S iron and steel sector. A number of early-stage efficient technologies (i.e., emerging or demonstration technologies) are technically feasible and have the potential to make a significant contribution to energy saving and CO 2 emissions reduction, but fall short economically to be included. However, they may also have the cost effective potential for significant cost reduction and/or performance improvement in the future under learning effects such as ‘learning-by-doing’. The investigation is carried out using ISEEM, a technology oriented, linear optimization model. We investigated how steel demand is balanced with/without the availability learning curve, compared to a Reference scenario. The retrofit (or investment in some cases) costs of energy efficient technologies decline in the scenario where learning curve is applied. The analysis also addresses market penetration of energy efficient technologies, energy saving, and CO 2 emissions in the U.S. iron and steel sector with/without learning impact. Accordingly, the study helps those who use energy models better manage the price barriers preventing unrealistic diffusion of energy-efficiency technologies, better understand the market and learning system involved, predict future achievable learning rates more accurately, and project future savings via energy-efficiency technologies with presence of learning. We conclude from our analysis that, most of the existing energy efficiency technologies that are currently used in the U.S. iron and steel sector are cost effective. Penetration levels increases through the years, even though there is no price reduction. However, demonstration technologies are not economically feasible in the U.S. iron and steel sector with the current cost structure. In contrast, some of the demonstration technologies are adapted in the mid-term and their penetration levels increase as the prices go down with learning curve. We also observe large penetration of 225kg pulverized coal injection with the presence of learning.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2012

White Paper on Energy Efficiency Status of Energy-Using Products in China (2011)

This White Paper focuses on the areas and products involved in the above tasks, based on the White Paper - Energy Efficiency Status of Energy-Using Products in China (2010), here referred to as “White Paper 2010”, which analyzed the energy efficiency status of 21 typical energy-using products in five sectors: household appliances, office equipment, commercial equipment, industrial equipment, and lighting equipment. Table 1 illustrates the detailed product coverage for this year’s paper, noting the addition of three household appliance items (automatic electric rice cooker, AC electric fan, and household induction cooktop) and one industrial sector item (three-phase distribution transformer).

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2016

A survey on software methods to improve the energy efficiency of parallel computing

Energy consumption is one of the top challenges for achieving the next generation of supercomputing. Codesign of hardware and software is critical for improving energy efficiency (EE) for future large-scale systems. Many architectural power-saving techniques have been developed, and most hardware components are approaching physical limits. Accordingly, parallel computing software, including both applications and systems, should exploit power-saving hardware innovations and manage efficient energy use. In addition, new power-aware parallel computing methods are essential to decrease energy usage further. This article surveys software-based methods that aim to improve EE for parallel computing. It reviews the methods that exploit the characteristics of parallel scientific applications, including load imbalance and mixed precision of floating-point (FP) calculations, to improve EE. In addition, this article summarizes widely used methods to improve power usage at different granularities, such as the whole system and per application. In particular, it describes the most important techniques to measure and to achieve energy-efficient usage of various parallel computing facilities, including processors, memories, and networks. Overall, this article reviews the state-of-the-art of energy-efficient methods for parallel computing to motivate researchers to achieve optimal parallel computing under a power budget constraint.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2018

Valuing Energy Efficiency and Distributed Energy Resources in the Built Environment: Preprint

Traditionally, analytical frameworks that underpin building energy policy have focused on the need to reduce annual energy consumption by assessing the cost and efficiency performance of energy-consuming technologies. Investments in distributed energy resources (DERs) such as photovoltaics have generally been evaluated independently, but also on a cost and performance basis. However, buildings are rapidly evolving to incorporate technologies that not just consume energy, but also generate, store, and control energy loads. Concurrently, the electric grid is becoming more dynamic and variable due to the increased proportion electricity production from variable renewable sources. To that end, building energy policy analytical frameworks should be updated to include the interactions between energy efficiency and DERs as well as potential value streams for the grid and building owner that technologies or packages of technologies might offer. As buildings with DERs and controllable loads are able to provide grid services or optimize operations based on electricity rates and grid conditions, the temporal and spatial nature of these technologies should also be incorporated into design decisions. To explore these questions further, the National Renewable Energy Laboratory will use a series of building and electric grid models to simulate the design and operation of a neighborhood of buildings under various electricity rates, grid conditions, and potential compensation scenarios. Scenarios of time-sensitive values for future grid services will also be constructed for use in the analysis. New metrics that can be used in building energy policies will also be explored to capture the responsiveness or flexibility of high efficiency buildings with DERs under various electric grid conditions and future scenarios.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2018

Valuing Energy Efficiency and Distributed Energy Resources in the Built Environment

Traditionally, analytical frameworks that underpin building energy policy have focused on the need to reduce annual energy consumption by assessing the cost and efficiency performance of energy-consuming technologies. Investments in distributed energy resources (DERs) such as photovoltaics have generally been evaluated independently, but also on a cost and performance basis. However, buildings are rapidly evolving to incorporate technologies that not just consume energy, but also generate, store, and control energy loads. Concurrently, the electric grid is becoming more dynamic and variable due to the increased proportion electricity production from variable renewable sources. To that end, building energy policy analytical frameworks should be updated to include the interactions between energy efficiency and DERs as well as potential value streams for the grid and building owner that technologies or packages of technologies might offer. As buildings with DERs and controllable loads are able to provide grid services or optimize operations based on electricity rates and grid conditions, the temporal and spatial nature of these technologies should also be incorporated into design decisions. To explore these questions further, the National Renewable Energy Laboratory will use a series of building and electric grid models to simulate the design and operation of a neighborhood of buildings under various electricity rates, grid conditions, and potential compensation scenarios. Scenarios of time-sensitive values for future grid services will also be constructed for use in the analysis. New metrics that can be used in building energy policies will also be explored to capture the responsiveness or flexibility of high efficiency buildings with DERs under various electric grid conditions and future scenarios.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

Energy Efficiency Resources to Support State Energy Planning

An early step for most energy efficiency planning is to identify and quantify energy savings opportunities, and then to understand how to access this potential. The U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy offers resources that can help with both of these steps. This fact sheet presents those resources. The resources are also available on the DOE State and Local Solution Center on the "Energy Efficiency: Savings Opportunities and Benefits" page: https://energy.gov/eere/slsc/energy-efficiency-savings-opportunities-and-benefits.

building energy codes↗