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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 703 records · Page 39
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Effect of positive pulse charge waveforms on the energy efficiency of lead-acid traction cells

The effects of four different charge methods on the energy conversion efficiency of 300 ampere hour lead acid traction cells were investigated. Three of the methods were positive pulse charge waveforms; the fourth, a constant current method, was used as a baseline of comparison. The positive pulse charge waveforms were: 120 Hz full wave rectified sinusoidal; 120 Hz silicon controlled rectified; and 1 kHz square wave. The constant current charger was set at the time average pulse current of each pulse waveform, which was 150 amps. The energy efficiency does not include charger losses. The lead acid traction cells were charged to 70 percent of rated ampere hour capacity in each case. The results of charging the cells using the three different pulse charge waveforms indicate there was no significant difference in energy conversion efficiency when compared to constant current charging at the time average pulse current value.

Smithrick, J. J.↗
DOE OSTI2014

Assessing the Feasibility of Comprehensive Energy Efficiency Upgrades at Potawatomi Carter Casino Hotel

The Forest County Potawatomi Community, a federally-recognized Indian Tribe with a strong commitment to the natural environment, sought and obtained funding to investigate energy efficient improvements to its Potawatomi Carter Casino & Hotel and the adjacent Potawatomi Carter C-Store and Smoke Shop. The resulting energy studies recommended energy conservation measures that would collectively reduce energy use by more than 30% at the facilities and would save approximately $200,000 per year in energy costs. Consistent with its commitment to the natural environment, and to advance its goal of energy independence using Carbon free or Carbon neutral renewable resources, the Community has already begun implementing certain measures and continues to seek funding sources necessary to implement the remaining measures.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2022

Better Buildings Workforce Accelerator – Technical Assistance Project: Northwest Energy Efficiency Council – A Replicable Analysis for Building Operator Certification Diversity, Equity, and Inclusion Objectives

The Northwest Energy Efficiency Council (NEEC) requested technical assistance through the U.S. Department of Energy (DOE) Better Buildings Workforce Accelerator (BBWA) program, with the objective of developing a replicable analytical approach to understanding Building Operator Certification (BOC) program participants and measure progress towards diversity, equity, and inclusion objectives. The technical assistance advances NEEC’s progress towards their goal of recruiting more diverse students to the BOC training and certification program. This report develops a replicable geospatial analysis of BOC program participants based on DEI indicators that can be applied at a national level, provides a step-by-step guide on repeating and updating the analysis, and presents recommendations for future data collection and analysis.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2024

Importance of Window Installation in Residential Building Envelopes Having Continuous External Insulation in Order to Realize Energy Efficiency

Residential buildings are one of the prime candidates in the United States for reducing energy consumption. Continuous exterior insulation (CEI) is being used increasingly often in residential buildings to improve energy efficiency. Windows constitute 15–40% of a building envelope and are the weakest component in energy performance. The installation of windows in walls with CEI has not been well evaluated. We identified four cases of installing windows in walls with CEI of 25–76 mm (1–3 in.) thickness and analyzed the energy loss between the window and wall interface (flanking loss), structural issues, air leakage, and moisture penetration. Thermal analysis showed that the insulation value (RSI) of the 305 mm (12 in.) perimeter wall surrounding a window decreased by 7.6–34.5% in the four cases when compared with the RSI of the wall without the window. A window installation method is proposed to address the issues likely to occur with installation methods currently being used in the field. An out-of-the-box installation system was also designed to achieve a better thermal performance, cost effectiveness, and structural performance in high-performance residential buildings.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2020

Chapter 17: Residential Behavior Evaluation Protocol. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures, September 2011 - August 2020

This document has been updated in August 2020. This document was developed for the U.S. Department of Energy Uniform Methods Project (UMP). The UMP provides model protocols for determining energy and demand savings that result from specific energy-efficiency measures implemented through state and utility programs. In most cases, the measure protocols are based on a particular option identified by the International Performance Verification and Measurement Protocol; however, this work provides a more detailed approach to implementing that option. Each chapter is written by technical experts in collaboration with their peers, reviewed by industry experts, and subject to public review and comment. The protocols are updated on an as-needed basis. The UMP protocols can be used by utilities, program administrators, public utility commissions,evaluators, and other stakeholders for both program planning and evaluation. To learn more about the UMP, visit the website, https://energy.gov/eere/about-us/ump-home, or download the UMP introduction document at http://www.nrel.gov/docs/fy17osti/68557.pdf.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2024

Ambient energy for buildings: Beyond energy efficiency

The following Key Messages comprise the salient findings of this study: 1. Ambient energy (from sun, air, ground, and sky) can heat and cool buildings; provide hot water, ventilation and daylighting; dry clothes; and cook food. These services account for about three-quarters of building energy consumption and a third of total US demand. Biophilic design (direct and indirect connections with nature) is an intrinsic adjunct to ambient energy systems, and improves wellness and human performance. 2. The current strategy of electrification and energy efficiency for buildings will not meet our climate goals, because the transition to an all-renewable electric grid is too slow. Widespread adoption of ambient energy is needed. Solar-heated buildings also flatten the seasonal demand for electricity compared to all-electric buildings, reducing required production capacity and long-term energy storage. In addition, ambient-conditioned buildings improve resilience by remaining livable during power outages. 3. National policies, incentives, and marketing should be enacted to promote ambient energy use. Federal administrative priorities should reflect the importance of ambient energy for buildings. Use of ambient energy should be encouraged through existing and new building codes and standards. 4. Ambient energy system design tools are needed for architects, engineers, builders, building scientists, realtors, appraisers, and consumers. PVWatts is used over 100 million times per year for photovoltaic system design. A similar, simple, and accessible tool for ambient design is crucial. 5. Training on ambient energy is needed throughout secondary, post-secondary, and continuing education for workforce development. Currently, only about 10% of colleges teach courses on passive heating and cooling systems. 6. Ambient-conditioned buildings should be demonstrated in all US climate zones. Performance should be monitored and reported, with quantitative case studies made widely available. 7. While current technology is sufficient to build high-performance ambient buildings now, research is needed to develop new technologies to harness ambient energy more effectively and more economically. Such advancements will facilitate adoption of ambient energy technologies in a wider range of buildings, including retrofits. Examples include windows with much lower thermal losses, use of the building shell as thermal storage, alternative light-weight thermal storage systems, sky radiation cooling systems, automated controls for solar gains and passive cooling, and ground coupling.

14 SOLAR ENERGY↗
DOE OSTI2024

Maximizing energy efficiency in wastewater treatment plants: A data-driven approach for waste heat recovery and an economic analysis using Organic Rankine Cycle and thermal energy storage

Maximizing energy efficiency through waste heat recovery (WHR) processes is crucial for sustainable and ecofriendly operations across multiple industries, notably in wastewater treatment plants (WWTPs). This work proposes a comprehensive approach for assessing the WHR feasibility in WWTPs, structured in two main objectives. Firstly, an Artificial Neural Network (ANN) model is developed to accurately predict WHR based on operational data, including biogas temperature, biogas pressure, daily production in kWh, and WHR values in kWh th . The second objective focuses on economically evaluating the WHR feasibility based on the estimated WHR values obtained by the ANN model, and then realistically assessing the economic feasibility of integrating the Organic Rankine Cycle (ORC) and Seasonal Thermal Energy Storage (STES) systems. With an application to the As-Samra WWTP located in Jordan, the developed ANN model demonstrates promising results in the validation phase, with a root mean square error (RMSE) of 2206 kWh/day, a mean absolute error (MAE) of 1674 kWh/day, and an R-squared (R 2 ) value of 68%. On the other hand, the economic analysis reveals that an optimal ORC system of 412.14 kW e capacity yields a Net Present Value (NPV) of 2.09 million US dollars, a Levelized Cost of Energy (LCOE) of 0.0749 USD/kWh, a Payback Period (PBP) of 4.8 years, and annual revenues of 428 kUSD. This work also investigates the techno-economic feasibility of integrating ORC-STES. Results indicate that the LCOE and PBP are highly affected by the ORC's capital cost, and integrating STES increases the LCOE to 0.0824 USD/kWh, rendering its integration with ORC infeasible. In conclusion, this study aims to advance the understanding and application of WHR in WWTPs, paving the way for more efficient and sustainable practices in the field.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
NASA NTRS2016

Energy Efficient Cryogenics

The Cryogenics Test Laboratory, NASA Kennedy Space Center, works to provide practical solutions to low-temperature problems while focusing on long-term technology targets for the energy-efficient use of cryogenics on Earth and in space.

Energy↗
DOE OSTI2018

Estimating Residential Appliance Lifetime for Energy Efficient Policy Analysis

Accurate knowledge of appliance lifetimes helps policy makers set effective energy efficiency policy. The cost-effectiveness of an appliance efficiency measure depends on the length of time consumers will use an appliance. National shipments projections depend on the rate of replacement in the installed appliance stock. Furthermore, early retirement programs need an accurate understanding of the remaining useful life in order to calculate lifetime savings and cost-effectiveness of a program. This paper uses a method for calculating lifetime of appliances based on the most recent data available on appliance shipments, total appliance stock, and the fraction of surviving appliances by age bins. An example of the calculation methodology is provided for residential gas boilers. This paper concludes by comparing the results to other available data on gas boiler lifetime.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
NASA NTRS1980

The Energy Efficient Engine /E3/ - Advancing the state of the art

The NASA-sponsored Energy Efficient Engine (E3) Program, intended to develop and demonstrate the technology for reducing fuel consumption in future environmentally acceptable turbofan engines, is presented. The development of the flight propulsion system design is outlined and the resulting preliminary design is presented. Component design and subcomponent supporting technology verification work in progress is discussed, with attention given to fabrication development, the transition duct, mixer design, the fan, the high-pressure compressor, the combustor, and the high-pressure turbine. It is noted that the detailed design of the core components is essentially complete and fabrication of the hardware has begun, with the program on schedule toward testing in 1982.

Gardner, W. B.↗
NASA NTRS1981

Energy efficient engine component development and integration program

The technology that will improve the energy efficiency of propulsion systems for subsonic commercial aircraft is investigated. A reduction of 14.4% in cruise installed sfc (0.572 versus 0.668 for the CF6-50C) and a direct operation cost reduction in excess of the 5% goal is projected. Noise and emissions projections are consistent with the established goals.

Source record↗
NASA NTRS1980

Results of design studies and wind tunnel tests of an advanced high lift system for an Energy Efficient Transport

The development of an advanced technology high lift system for an energy efficient transport incorporating a high aspect ratio supercritical wing is described. This development is based on the results of trade studies to select the high lift system, analysis techniques utilized to design the high lift system, and results of a wind tunnel test program. The program included the first experimental low speed, high Reynolds number wind tunnel test for this class of aircraft. The experimental results include the effects on low speed aerodynamic characteristics of various leading and trailing edge devices, nacelles and pylons, aileron, spoilers, and Mach and Reynolds numbers. Results are discussed and compared with the experimental data and the various aerodynamic characteristics are estimated.

Oliver, W. R.↗
DOE OSTI2022

Behavioral Changes for Energy Efficiency: An Exploratory Analysis of the CanBikeCO Mini-Pilot

Behavioral Changes for Energy Efficiency: an exploratory analysis of the CanBikeCO mini-pilot While the results are strongly positive, the small sample size, narrow demographic profile, and limited mobility alternatives for program participants indicate caution in broader interpretation. However, they do provide the tantalizing possibility that such programs can meet equity and sustainability goals simultaneously.

ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2022

User Friendly Web-Based Tool to Assess the Energy Efficiency and Durability of Residential Wall Retrofits

According to the U.S. Department of Energy Windows and Building Envelope Research and Development Roadmap for Emerging Technologies, building envelope wall energy loss in the United States accounts for about 5.9 x 1010 kWh or 2 quads of energy annually, costing homeowners and occupants billions of dollars. Enclosure retrofits targeting these losses can save significant energy, reduce greenhouse gas emissions, and save occupants millions of dollars over time. Older homes, built before 1992 when DOE’s Building Energy Codes Program was established, represent approximately 68 percent of the residential building stock in the country, often having significant air leakage and inadequate insulation. Homes with little to no air sealing or insulation have heating and cooling losses that can represent a substantial portion of utility bills.High-performance building envelope retrofit systems are rarely selected for retrofit applications. Current solutions are expensive and/or unfamiliar to many designers, builders, contractors, and code officials and therefore are perceived as risky. The dominant perceived risk is durability specifically related to condensation and moisture accumulation in the building envelope component.The Building Science Advisor (BSA) is a rule-based expert system web-based tool that was originally developed to assist building professionals in designing energy efficient and durable wall systems for new construction. With the present focus being placed on upgrading the existing building stock, a retrofit module has been developed that, based on the location, existing construction, and planned retrofit strategy, provides recommendations on how to address the retrofit in a manner that will perform in accordance with IECC 2018 building code and not create a durability problem. This paper will describe the development of this tool and demonstrate its features and capabilities.

Desjarlais, Andre Omer↗
DOE OSTI2016

Turnkey Heating, Ventilating, and Air Conditioning and Lighting Retrofit Solution Combining Energy Efficiency and Demand Response Benefits

NREL worked with the Bonneville Power Administration's Technology Innovation Office to demonstrate a turnkey, retrofit technology that combines demand response (DR) and energy efficiency (EE) benefits for HVAC and lighting in retail buildings. As a secondary benefit, we also controlled various plug loads and electric hot water heaters (EHWH). The technology demonstrated was Transformative Wave's eIQ Building Management System (BMS) automatically responding to DR signals. The BMS controlled the HVAC rooftop units (RTU) using the CATALYST retrofit solution also developed by Transformative Wave. The non-HVAC loads were controlled using both hardwired and ZigBee wireless communication. The wireless controllers, manufactured by Autani, were used when the building's electrical layout was too disorganized to leverage less expensive hardwired control. The six demonstration locations are within the Seattle metro area. Based on the assets curtailed by the BMS at each location, we projected the DR resource. We were targeting a 1.7 W/ft2 shed for the summer Day-Ahead events and a 0.7 W/ft2 shed for the winter events. While summarized in Table ES-1, only one summer DR event was conducted at Casino #2.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

Coeur d’Alene Tribe Benewah Market Energy Efficiency Project Final Technical Report

The Coeur d’Alene Reservation has been the home of the Coeur d’Alene Tribe since time immemorial and it is fitting that the Tribe’s name in the Coeur d’Alene language is schitsu’umsh, “the ones who were found here.” The Reservation is located in northern Idaho, is approximately 345,000 acres and is comprised of forest land, agricultural land, several streams, Coeur d’Alene Lake and the St. Joe River and a small amount of developed land. The project area was conducted within the boundaries of the Coeur d’Alene Reservation. The population of the Reservation is 6,760 (2010 Census). Currently, there are approximately 2,463 enrolled Coeur d’Alene Tribal members (Coeur d’Alene Tribe Enrollment 2016). The Benewah Market is a Tribally-owned and operated facility located at 1111 B St. Plummer, ID 83851. The Benewah Market is an approximately 23,500 square foot single-story structure. The majority of the building is occupied by a grocery store with a full meat department, deli, and bakery. Approximately 20% of the floor area at the northeast corner is occupied by an Ace Hardware retailer. The largest part of the building is approximately 17,000 square feet, is separately metered and houses the grocery store which was constructed in 1984. The market is the largest full service market serving the Coeur d’Alene Reservation and is the only full service market in a 35-mile radius. The Tribe has benefited greatly from the Benewah Market Energy Efficiency Project and will continue to do so for many years: The health and safety of the food has been improved greatly now that the refrigeration and freezer cases are at a constant and safe temperature on a monitoring and alarm system. There is no longer a thaw and freeze cycle that allows fluctuations in temperature. If the power goes out, there is an immediate alarm and contact so that time may be tracked and food kept safe during an outage. The overall annual energy use in the Benewah Market has dropped by 22.9% -Energy costs for the Market decreased by an estimated 11,620 dollars in one year due to this project. The Tribe has seen an increase in the cost of energy from Plummer Power and this was offset by the reduction in energy consumed. This estimate assumes that the Tribe would have consumed the same amount of energy as the prior year. -Maintenance costs are estimated to have decreased by $10,000 in just the one year since installation in contract repair and maintenance. The Tribe estimates that it has saved 24,000 dollars over a one-year time period in labor costs to maintain the older system. Due to having a more efficient store, with safer, more attractive display of food and lower energy and maintenance costs, the store is able to be more viable economically. The store has increased its sales and has been able to pass along operations and maintenance savings to its customers and employees. The Tribe hosted a ribbon-cutting ceremony on February 28, 2017 at the Benewah Market with Chris Deschene, then Office of Indian Energy Director, as well as representatives from the Coeur d’Alene Tribe and Bonneville Power Administration. While the ribbon-cutting ceremony was going on, the Tribe’s media outlets covered the ceremony and placed information about the project on the Tribe’s Facebook page on two separate occasions. The Coeur d’Alene Tribe’s Natural Resources Department and the Tribe’s Development Corporation are thankful for the opportunity that the Benewah Market Energy Efficiency Project has afforded the Coeur d’Alene Tribal community. Without the U.S. Department of Energy’s Indian Energy Program funding and its dedicated staff, this project would not have been completed. This has been a lot of work for all parties involved but has provided benefits to thousands of people for many years to come.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2014

Energy Efficiency Pilot Projects in Jaipur: Testing the Energy Conservation Building Code

The Malaviya National Institute of Technology (MNIT) in Jaipur, India is constructing two new buildings on its campus that allow it to test implementation of the Energy Conservation Building Code (ECBC), which Rajasthan made mandatory in 2011. PNNL has been working with MNIT to document progress on ECBC implementation in these buildings.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗