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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 415 records · Page 23

Commercial Midstream Energy Efficiency Incentive Programs: Guidelines for Future Program Design, Implementation, and Evaluation

Many electric utilities operate energy efficiency incentive programs that encourage increased dissemination and use of energy-efficient (EE) products in their service territories. The programs can be segmented into three broad categories—downstream incentive programs target product end users, midstream programs target product distributors, and upstream programs target product manufacturers. Traditional downstream programs have had difficulty engaging Small Business/Small Portfolio (SBSP) audiences, and an opportunity exists to expand Commercial Midstream Incentive Programs (CMIPs) to reach this market segment instead.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Residential Energy Efficiency Design Guide for Tribal Lands

Homeowners and renters on tribal lands have historically faced a disproportionate energy burden compared to the United States as a whole. The Indian Health Service (IHS), which serves these communities, strives to meet aggressive energy performance goals when constructing their residential housing. Challenges common in rural locations can hinder progress toward those goals, such as availability of materials, access to specialized labor, and budget constraints. This guide is for architects and builders who aim to incorporate energy efficiency (EE) into their residential designs. This report presents commercially viable energy efficiency packages for a variety of locations and home inputs to help guide home builders in choosing improvements for energy performance. The intention is to provide a diverse set of packages that can be used during the design phase to achieve energy savings compared to a code minimum building design. By presenting a set of diverse options with similar expected energy savings and life-cycle costs, final decisions can be left up to the building designers who can better determine the appropriate package given local costs, materials, and labor availability. Although this guide was developed for IHS projects, it can be used to help designers and construction professionals better make cost-effective choices when a detailed, project-specific building energy analysis is not possible.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Recovery Act - CAREER: Sustainable Silicon -- Energy-Efficient VLSI Interconnect for Extreme-Scale Computing

The research goal of this CAREER proposal is to develop energy-efficient, VLSI interconnect circuits and systems that will facilitate future massively-parallel, high-performance computing. Extreme-scale computing will exhibit massive parallelism on multiple vertical levels, from thou­ sands of computational units on a single processor to thousands of processors in a single data center. Unfortunately, the energy required to communicate between these units at every level (on­ chip, off-chip, off-rack) will be the critical limitation to energy efficiency. Therefore, the PI's career goal is to become a leading researcher in the design of energy-efficient VLSI interconnect for future computing systems.

97 MATHEMATICS AND COMPUTING↗

Energy efficient engine high-pressure turbine detailed design report

The energy efficient engine high-pressure turbine is a single stage system based on technology advancements in the areas of aerodynamics, structures and materials to achieve high performance, low operating economics and durability commensurate with commercial service requirements. Low loss performance features combined with a low through-flow velocity approach results in a predicted efficiency of 88.8 for a flight propulsion system. Turbine airfoil durability goals are achieved through the use of advanced high-strength and high-temperature capability single crystal materials and effective cooling management. Overall, this design reflects a considerable extension in turbine technology that is applicable to future, energy efficient gas-turbine engines.

Thulin, R. D.↗

State Energy Efficient Appliance Rebate Program (SEEARP) Reports

The State Energy Efficient Appliance Rebate Program (SEEARP) reports database includes rebate reports (xls) and summary factsheets (pdf) from states and territories that participated in SEEARP. With funding provided by the American Recovery and Reinvestment Act of 2009 (ARRA), the U.S. Department of Energy (DOE) developed SEEARP to spur economic activity and invest in long-term energy savings by helping consumers replace older, inefficient appliances with new, efficient models. SEEARP provided almost $300 million to the 56 U.S. states and territories to support state-level consumer rebate programs for efficient appliances from December 1, 2009 to February 17, 2012. The successes and challenges of SEEARP provide valuable lessons for designing and running a consumer-focused appliance rebate program. In addition to the SEEARP reports database, the two reports included provide a results and program design lessons.

appliances↗

Energy Efficiency of Low-Temperature Deaeration of Makeup Water for a District Heating System

It is shown that the temperature of makeup water in district heating systems has a strong effect on the energy efficiency of turbines of thermal power plants. A low-temperature deaeration process that considerably improves the energy efficiency of thermal power plants is developed. The desorbing agent is the gas supplied to the burners of the boiler. The energy efficiency of the process for a typical unit of thermal power plant is assessed.

42 ENGINEERING↗

Energy-efficient sorption-based gas clothes dryer systems

Standard electric resistance and fuel-driven dehydration technologies exhibit a maximum coefficient of performance of well below 1 mainly due to enthalpy losses associated with the air leaving the dehydration system. To improve energy efficiency, condensing dryer systems condense the moisture captured from a product in a closed-loop air circulation cycle. Existing condensing dehydration systems including heat pump dryers, however, need to significantly cool the air to achieve dehumidification. The added cooling and subsequent heating to return the air to a desired drying temperature consume substantial energy and thus reduce drying performance. Here, an innovative sorption-based gas dehydration system is proposed to overcome barriers deteriorating energy efficiency in existing gas, electric, or heat pump dryer systems. Decoupling latent and sensible loads, the system employs a liquid-desiccant solution to directly capture air humidity, thereby allowing circulation of the air in a closed loop to achieve high drying energy efficiency. In other words, the system captures waste latent heat from the moisture produced during the dehydration process and reuses it to improve energy efficiency. This study focuses on a comprehensive quasi-steady-state thermodynamic modeling of the proposed sorption-based dehydration concept employed for a gas clothes dryer application to predict transient response and overall drying performance (i.e., time and energy metrics). The analysis indicates the proposed sorption-based gas clothes dryer system can deliver a specific moisture extraction rate of 1.71 kg of water per kWh (i.e., a combined energy factor of 3.167 kg (6.98 lbm) of dry cloth per kWh) with a drying time of 44 min. This is a 112% energy improvement compared with state-of-the-art gas clothes dryers exhibiting a combined energy factor of 1.50 kg (3.3 lbm) of dry cloth per kWh. The technology pursued here can potentially be employed as a platform for many fuel-driven equipment to take advantage of available waste thermal energy in the environment instead of simply burning a fuel.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Energy efficiency evaluation of a stationary lithium-ion battery container storage system via electro-thermal modeling and detailed component analysis

Energy efficiency is a key performance indicator for battery storage systems. A detailed electro-thermal model of a stationary lithium-ion battery system is developed and an evaluation of its energy efficiency is conducted. The model offers a holistic approach to calculating conversion losses and auxiliary power consumption. Sub-models for battery rack, power electronics, thermal management as well as the control and monitoring components are developed and coupled to a comprehensive model. The simulation is parametrized based on a prototype 192 kWh system using lithium iron phosphate batteries connected to the low voltage grid. The key loss mechanisms are identified, thoroughly analyzed and modeled. Generic profiles featuring various system operation modes are evaluated to show the characteristics of stationary battery systems. Typically the losses in the power electronics outweigh the losses in the battery at low power operating points. The auxiliary power consumption dominates for low system utilization rates. For estimation of real-world performance, the grid applications Primary Control Reserve, Secondary Control Reserve and the storage of surplus photovoltaic power are evaluated. Conversion round-trip efficiency is in the range of 70-80%. Finally, overall system efficiency, which also considers system power consumption, is 8-13 percentage points lower for Primary Control Reserve and the photovoltaic-battery application. However, for Secondary Control Reserve, the total round-trip efficiency is found to be extremely low at 23% due to the low energy throughput of this application type.

25 ENERGY STORAGE↗

Putting Data to Work: Using Building Energy Performance Data to Expand the Market for Energy Efficiency in Buildings

An increasing number of state and local jurisdictions are implementing building performance reporting laws, which generate large quantities of useful data on the characteristics and resource consumption of the building stock. Yet, to realize the potential of these policies, the data must not only be disclosed, but put to work to drive energy savings. Under a three-year pilot, Washington DC (DC), New York City (NYC) and their partners are pioneering the use of data from building performance reporting in energy efficiency programs. To minimize the administrative burden of managing, combining, and sharing these data sets, the cities are utilizing the U.S. Department of Energy’s (DOE) open-source Standard Energy Efficiency Data (SEED) Platform. The Putting Data to Work project team is working with efficiency program administrators to develop and implement new and innovative ways in which the data collected through benchmarking, energy audits, and related policies can be used to improve energy policies and planning, unlock data directly for market use, scale-up the market for energy efficiency services, drive competition, better target utility incentive programs, and inform measurement and verification. This paper details achievements and key findings in DC and NYC to date, including the importance of high compliance, data quality, and data cleansing in using the information collected; methods that the cities are using to apply data to drive maximum energy efficiency; and the importance of inter- and intra-agency collaboration in program success. We also outline the path forward and detail expected outcomes and scalability of project activities.

Beddingfield, Erin↗

Results of NASA's Energy Efficient Engine Program

The major activity undertaken in the NASA Energy Efficient Engine Program has been completed. This paper reports on the progress made toward achieving the program goal of developing advanced technology to significantly reduce fuel consumption and operating costs of future subsonic transport-type propulsion systems. An additional goal was that the advanced concepts be compatible with future environmental regulations. Along with the results obtained, a brief overview of the design details of both the General Electric and Pratt and Whitney energy efficient engines and the overall program scope are presented. Overall, this program has been highly successful; the technology developed during its course is, and will continue to be, effectively employed in both current and future advance transport aircraft engine designs.

Ciepluch, Carl C.↗

Boosting Energy Efficiency and Economic Development through Chambers of Commerce (Final Technical Report)

The U.S. Department of Energy’s (DOE) Building Technology Office (BTO), in its mission to improve energy efficiency in commercial and residential buildings, recognized the unique challenges posed by small- and medium-sized commercial buildings. This project targeted these buildings by using a business-to-business model originally pioneered in Cleveland, Ohio, by the Greater Cleveland Partnership’s Council of Smaller Enterprises (COSE). Rather than attempting to take programs and materials designed for large commercial buildings and simply disseminate them to owners of small- and medium-sized buildings, COSE targeted the tenants and owners of these buildings directly through existing business partnership channels and built additional business partnerships with banks willing to finance cost-effective retrofits, and leveraging utility efficiency programs that enabled them to provide free audits via an established network of auditors. By delivering a customized message to their members and leveraging their connections in the local business community, Chambers of Commerce and other business-oriented organizations use their existing relationship and trust to deliver clear and concise messages about the opportunities, impacts, and value of energy efficiency investments.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

A Mulit-State Model for Catalyzing the Home Energy Efficiency Market

The RePower Kitsap partnership sought to jump-start the market for energy efficiency upgrades in Kitsap County, an underserved market on Puget Sound in Washington State. The Washington State Department of Commerce partnered with Washington State University (WSU) Energy Program to supplement and extend existing utility incentives offered by Puget Sound Energy (PSE) and Cascade Natural Gas and to offer energy efficiency finance options through the Kitsap Credit Union and Puget Sound Cooperative Credit Union (PSCCU). RePower Kitsap established a coordinated approach with a second Better Buildings Neighborhood Program project serving the two largest cities in the county – Bainbridge Island and Bremerton. These two projects shared both the “RePower” brand and implementation team (Conservation Services Group (CSG) and Earth Advantage).

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Selling an Energy Efficiency Loan Portfolio in Oregon: Resale of the Craft3 loan portfolio to Self-Help Credit Union

Under the Clean Energy Works (CEW) program, Craft3 developed a loan product that widened access to financing for homeowners, offered long term funding, and collected repayments through the customer?s utility bill. The program?s success led Craft3 to pursue the sale of the loan portfolio to both mitigate its own risks and replenish funds for lending. This sale breaks new ground for energy efficiency finance and is notable as it was completed even with many novel program design elements. It replenished Craft3?s program capital and uncovered some valuable lessons that may facilitate future transactions. However, the lack of data history and the unproven nature of the loan portfolio meant that Craft3 had to limit the risk of losses to Self-Help, the purchaser of the portfolio. It remains to be seen whether this experience will pave the way for more sales of on-bill energy efficiency loan portfolios. This case study illustrates how certain program design decisions can sometimes both facilitate programmatic objectives and possibly present challenges for the sale of a portfolio of energy efficiency loans.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Energy-Efficient and Secure S-Box circuit using Symmetric Pass Gate Adiabatic Logic

Differential Power Analysis (DPA) attack is considered to be a main threat while designing cryptographic processors. In cryptographic algorithms like DES and AES, S-Box is used to indeterminate the relationship between the keys and the cipher texts. However, S-box is prone to DPA attack due to its high power consumption. In this paper, we are implementing an energy-efficient 8-bit S-Box circuit using our proposed Symmetric Pass Gate Adiabatic Logic (SPGAL). SPGAL is energy-efficient as compared to the existing DPAresistant adiabatic and non-adiabatic logic families. SPGAL is energy-efficient due to reduction of non-adiabatic loss during the evaluate phase of the outputs. Further, the S-Box circuit implemented using SPGAL is resistant to DPA attacks. The results are verified through SPICE simulations in 180nm technology. SPICE simulations show that the SPGAL based S-Box circuit saves upto 92% and 67% of energy as compared to the conventional CMOS and Secured Quasi-Adiabatic Logic (SQAL) based S-Box circuit. From the simulation results, it is evident that the SPGAL based circuits are energy-efficient as compared to the existing DPAresistant adiabatic and non-adiabatic logic families. In nutshell, SPGAL based gates can be used to build secure hardware for lowpower portable electronic devices and Internet-of-Things (IoT) based electronic devices.

Kumar, Dinesh↗

Energy efficient engine component development and integration program

The objective of the Energy Efficient Engine Component Development and Integration program is to develop, evaluate, and demonstrate the technology for achieving lower installed fuel consumption and lower operating costs in future commercial turbofan engines. Minimum goals have been set for a 12 percent reduction in thrust specific fuel consumption (TSFC), 5 percent reduction in direct operating cost (DOC), and 50 percent reduction in performance degradation for the Energy Efficient Engine (flight propulsion system) relative to the JT9D-7A reference engine. The Energy Efficienct Engine features a twin spool, direct drive, mixed flow exhaust configuration, utilizing an integrated engine nacelle structure. A short, stiff, high rotor and a single stage high pressure turbine are among the major enhancements in providing for both performance retention and major reductions in maintenance and direct operating costs. Improved clearance control in the high pressure compressor and turbines, and advanced single crystal materials in turbine blades and vanes are among the major features providing performance improvement. Highlights of work accomplished and programs modifications and deletions are presented.

Source record↗

An ultra-efficient energy transfer beyond plasmonic light scattering

The energy transfer between nano-particles is of great importance for, solar cells, light-emitting diodes, nano-particle waveguides, and other photonic devices. This study shows through novel design and algorithm optimization, the energy transfer efficiency between plasmonic and dielectric nano-particles can be greatly improved. Using versatile designs including core-shell wrapping, supercells and dielectric mediated plasmonic scattering, 0.05 dB/μm attenuation can be achieved, which is 20-fold reduction over the baseline plasmonic nano-particle chain, and 8-fold reduction over the baseline dielectric nano-particle chain. In addition, it is also found that the dielectric nano-particle chains can actually be more efficient than the plasmonic ones, at their respective optimized geometry. The underlying physics is that although plasmonic nano-particles provide stronger coupling and field emission, the effect of plasmonic absorption loss is actually more dominant resulting in high attenuation. Finally, the group velocity for all design schemes proposed in this work is shown to be maintained above 0.4c, and it is found that the geometry optimization for transmission also boosts the group velocity.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Energy Efficiency Building Systems Regional Innovation Cluster Initiative

The Consortium for Building Energy Innovation (CBEI) was established through a Funding Opportunity Announcement led by the U.S. Department of Energy, under a cooperative agreement managed by the National Energy Technology Laboratory. CBEI is led by The Pennsylvania State University and is composed of partners from academia, the private sector, and economic development agencies. The Consortium has included as many as 24 different partners over the five years, but 14 have been core to the work over the five year cooperative agreement. CBEI primarily focused on developing energy efficiency solutions for the small and medium commercial building market, with a focus on buildings less than 50,000 square feet. This market has been underserved by the energy efficiency industry, which has focused on larger commercial buildings where the scale of an individual retrofit lends itself to the use of sophisticated modeling tools and more advanced solutions. Owners/operators and retrofit providers for larger buildings have a greater level of understanding of, and experience with different solutions. In contrast, smaller commercial building retrofits, like residential retrofits, often have owners with less knowledge about energy management and less time to learn about it. This market segment is also served by retrofit providers that are smaller and often focused on particular building systems, e.g. heating, ventilation and air conditioning (HVAC), lighting, roofing, or insulation. The size of a smaller commercial building retrofit does not lend itself, from a cost perspective, to the application of multiple, sophisticated design and modeling tools, which means that they are less likely to have integrated solutions.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Scaling Up Energy Efficiency Investment in Emerging Markets - Private Sector Perspectives

Since 2000, electricity demand has flattened and decoupled from Gross Domestic Product (GDP) growth in the Organization for Economic Cooperation and Development (OECD) countries. This trend is anticipated to continue for the next several decades and is largely attributed to the implementation of energy efficiency measures. However, non-OECD countries (emerging markets) have experienced, and are projected to continue experiencing, increasing electricity demands. If the world is to meet the requirements of the Paris Agreement, annual investments in clean energy and energy efficiency need to increase by a factor of six by 2050, compared to 2015. Information presented in this paper is based on qualitative and quantitative data collection and analysis methods to provide an empirical understanding of barriers to private sector clean energy investment including microgrid development, energy efficiency, smart grid development, and utility-scale wind and solar in emerging markets. Through literature review, a survey, and a series of webinar dialogues, USAID and the U.S. Department of Energy National Renewable Energy Laboratory (NREL) solicited input from private sector actors, including developers, project financiers, manufacturers and technical assistance service providers, on the challenges they face to market entry in emerging markets, and their suggestions for improving market competitiveness.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗