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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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Presentation on energy conversion on aircraft. Thermal energy recovery changes aircraft thermal management from being a necessary burden on aircraft performance to a desirable asset. It improves the engine performance by recycling waste heat and ultimately rejecting all collected aircraft heat out through the engine nozzle.
Formaldehyde (CH 2 O) is a highly versatile platform chemical with an annual production of over 30 megatons. The current most widely used industrial method for formaldehyde synthesis is very energy intensive and plagued with significant exergy losses. We propose a highly efficient heterogeneous nanoporous catalyst capable of direct hydrogenation of CO to CH 2 O followed by condensation of CH 2 O from a mixture of CO and H 2 , which are non-condensable gases. The key to this synthesis is a Lewis Pair (LP) functionalized metal-organic framework (MOF) heterogeneous porous catalyst. We have computed reaction pathways, barriers, and uncertainties for CO hydrogenation on a LP functionalized MOF using various density functional theory (DFT) methods and high-level ab initio methods. We have assessed the uncertainties in the energetics inherent in the DFT functionals. Here, we predict that the thermodynamics of CH 2 O synthesis will be enhanced relative to gas phase synthesis and more importantly, will not be equilibrium limited because the barrier to product desorption from the MOF is much lower than the barrier for the reverse reaction. Hence, the product will be continuously removed from the process, facilitating very high overall conversion rates. Our proposed process will dramatically improve the sustainability of CH 2 O synthesis.
Selective separation of HMF from the aqueous phase and integration with downstream reactions via a two-stage adsorption and desorption scheme.
The Lightwave Energy-Efficient Datacenter (LEED) program is a disruptive “green-field” approach that provides a quantum leap in the energy efficiency of datacenters. LEED’s fundamental value proposition is that a novel and re-architected optical network—RotorNet— can deliver “more bandwidth per buck” as well as unique system-level attributes that significantly improve overall datacenter energy efficiency and performance. LEED has developed three system-level testbeds. The first testbed uses calibrated hardware and software power measurements to determine server energy efficiency as a function of network bandwidth and workload. These measurements have shown that increasing network communications bandwidth dramatically increases server energy efficiency providing a realistic path to the overall ENLITENED program goal of doubling the number of transactions per joule. The second testbed demonstrates key hardware: a prototype low-loss, high-port count optical “selector switch”. This switch was fabricated, racked, and tested. Measured switch characteristics include loss, bandwidth, crosstalk, switch time, system-level switch time (including the transceivers), and bit error rate. The third testbed demonstrates a fully working and manufactured pinwheel design which dramatically lowers the cost of design, while delivering high switch radix and low reconfiguration times. The LEED project has tied these three novel photonic switch prototypes together with production servers and software through the development of a novel FPGA-based NIC platform called Corundum. Corundum ensures that the packet-switched protocols supported by commodity operating systems and devices can interface with the Rotor switch design. The LEED group has used this combined hardware and software prototype to characterize applications running at a commercially relevant scale. The project has used a combination of enhanced optical modulation amplitude (OMA) modulators, broadband multiplexers and demultiplexers, avalanche photodiodes, and a novel burst-mode receivers to enable the insertion of LEED-developed optical switches without the need for expensive optical amplification. Our modeling has shown that measured LEED-developed device characteristics can achieve link characteristics of 2 pJ/bit including both transceivers and the Rotor switch. In summary, the LEED program has demonstrated a credible and practical path, through novel hardware and software, to realize the program objectives of ENLITENED. The net result will ensure that the United States maintains its strength in the crucial sector of Information Technology, which is vital to both our economic security and our national security.
Increasing energy efficiency is ubiquitous in many economies, and several mechanisms for achieving this increase, from mandatory policies to voluntary initiatives, have been proposed and implemented. In the United States, the Department of Energy, during the development of its energy conservation standard rules, evaluates the benefits from several of these mechanisms. In this report, we review how estimates of benefits from two types of voluntary energy efficiency initiatives – rebates and voluntary energy efficiency targets (VETs) – compare to the same benefits estimated for minimum energy efficiency standards (MEPS) established in the United States for residential appliances, commercial and industrial equipment, and lighting applications (referred to simply as “products” for the remainder of this report) between 2010 and 2020. Our results show that, overall, these two voluntary measures are estimated to provide, altogether, 36% of the total energy savings estimated to be provided by new efficiency standards, with a total net-present value that corresponds to 52% of the net-present value estimated for standards. When considering all energy conservation rules reviewed in this report, the energy savings a rebate program is estimated to achieve ranges from less than 1% to 86% of the savings from new standards set for the same type of product and at the same level of energy efficiency. As for VETs, the energy savings range from less than 1% to 78% of the savings from standards. Results vary widely across types of products due to (a) the relevance of the monetary incentive relative to incremental upfront costs considered for each type of product, and (b) the estimated level of market barriers associated with each type of product. While voluntary energy efficiency initiatives are not as effective as MEPS in transforming the market and raising the bar of energy efficiency for energy consuming goods in an economy, when applied in tandem with MEPS they can be powerful instruments for promoting and increasing energy efficiency in the economy.
The Building Energy Asset Score is a national standardized tool for evaluating the physical and structural energy efficiency of commercial and multifamily residential buildings. The Asset Score generates a simple energy efficiency rating that enables comparison among buildings, and identifies opportunities for users to invest in energy efficiency upgrades. It is web-based and free to use. This fact sheet discusses the value of the score for utilities and energy efficiency program administrators.
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.
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.
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.
This resource is designed to help non-profit organizations promote energy efficiency in homes and reduce greenhouse gas emissions in communities by using DOE's Home Energy Score tool to help residents understand and improve home energy performance.
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.
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.
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.
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.
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.
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.
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