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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 343 records · Page 19
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Advanced Mixed Mode Combustor for Hydrogen F-Class Retrofit (Final Report)

This objective of this project was to develop a retrofittable combustor module for the GE Vernova Operations LLC (GE Vernova, GEV) frame 7F gas turbine (GT) that would allow operation on blends of hydrogen in Natural Gas (NG) between 0% and 100%. The new system was to be part of a package that retained current cycle performance while limiting the increase in NOx emissions to the equivalent of 25ppm (parts per million by volume dry at 15% O2, ppmvd15) with consideration for the impact of hydrogen fuel on the O2 correction. The expectation was that with the addition of Axial Fuel Staging (AFS), turndown within emission compliance would be extended to below 20% GT load. The original project plan included three budget periods (BPs): BP1 spanning October 1, 2022 through August 31, 2024; BP2 spanning September 1, 2024 through December 31, 2025; and BP3 spanning January 1, 2026 through September 30, 2026. The project was terminated early by the DOE on October 10, 2025 about three months prior to the end of BP2. BP3 activities were therefore cancelled. The program was on track to meet all objectives prior to the DOE termination. This Final Report covers work completed during BP1 and BP2 prior to the program termination.

08 HYDROGEN↗
NASA NTRS1973

Fleet retrofit report

Flight tests are evaluated of an avionics system which aids the pilot in making two-segment approaches for noise abatement. The implications are discussed of equipping United's fleet of Boeing 727-200 aircraft with two-segment avionics for use down to Category 2 weather operating minima. The experience is reported of incorporating two-segment approach avionics systems on two different aircraft. The cost of installing dual two-segment approach systems is estimated to be $37,015 per aircraft, including parts, labor, and spares. This is based on the assumption that incremental out-of-service and training costs could be minimized by incorporating the system at airframe overhaul cycle and including training in regular recurrent training. Accelerating the modification schedule could add up to 50 percent to the modification costs. Recurring costs of maintenance of the installation are estimated to be of about the same magnitude as the potential recurrent financial benefits due to fuel savings.

Source record↗
NASA NTRS1978

Greenbelt Community Project: Solar energy retrofit for a multi-family dwelling

A cooperative project was initiated between Goddard Space Flight Center and the nearby community of Greenbelt, Maryland. The purpose was to design, install and operate an experimental solar heating system on a group of four tandem town houses. The system was successfully developed and is operating. A description is given of the design, installation, system operation and performance as well as the important considerations for judging the economic feasibility of solar heating systems.

Hymowitz, E. W.↗
NASA NTRS1987

Design considerations for the beamwaveguide retrofit of a ground antenna station

A primary requirement of the NASA Deep Space Network (DSN) is to provide for optimal reception of very low signal levels. This requirement necessitates optimizing the antenna gain to the total system operating noise level quotient. Low overall system noise levels of 16 to 20 K are achieved by using cryogenically cooled preamplifiers closely coupled with an appropriately balanced antenna gain/spillover design. Additionally, high-power transmitters (up to 400 kW CW) are required for spacecraft emergency command and planetary radar experiments. The frequency bands allocated for deep space telemetry are narrow bands near 2.1 and 2.3 GHz (Ka-band), 7.1 and 8.4 GHz (X-band), and 32 and 34.5 GHz (Ka-band). In addition, planned operations for the Search for Extraterrestrial Intelligence (SETI) program require continuous low-noise receive coverage over the 1 to 10 GHz band. To summarize, DSN antennas must operate efficiently with low receive noise and high-power uplink over the 1 to 35 GHz band.

Veruttipong, T.↗
NASA NTRS1997

Retrofitting Laboratory Fume Hoods With Face Velocity Monitors at NASA Lewis Research Center

Extensive use and reliance on laboratory fume hoods exist at LeRC for the control of chemical hazards (nearly 175 fume hoods). Flow-measuring devices are necessary to continually monitor hood performance. The flow-measuring device should he tied into an energy management control system to detect problems at a central location without relying on the users to convey information of a problem. Compatibility concerns and limitations should always be considered when choosing the most effective flow-measuring device for a particular situation. Good practice on initial hood design and placement will provide a system for which a flow-measuring device may be used to its full potential and effectiveness.

Wagner, Ingrid E.↗
NASA NTRS1997

MEASUREMENT OF THE NOISE IMPROVEMENT OF A 34-METER CASSEGRAIN ANTENNA RETROFITTED WITH A LOW-BACKSCATTERING STRUT

Large axially-symmetric ground-based dual-reflector antennas are used in a variety of applications simultaneously requiring very high gain and very low noise (e.g., satellite communications, radio astronomy, deep-space communications, and radar). In these systems, reducing the noise by 10 % is equivalent to increasing the antenna gain by roughly 0.5 dB. Since the early days of radio-astronomy this fact has continuously driven efforts to reduce the noise of front-end low-noise amplifiers--a major noise contributor. As the performance of the front-end amplifiers improved, the relative importance of the noise generated by the surrounding warm ground increased, causing the antenna noise to become a major factor in the overall system sensitivity. Since large ground-based reflectors have been around for several decades, the various electrical and mechanical parameters affecting their performance have received considerable attention and are generally well understood. However, the impact of the subreflector supporting struts on the antenna noise performance remains a source of uncertainty. The reason for this stems from the usually large electrical dimensions involved, which precludes the accurate modeling of the various strut-scattering mechanisms. For the particular antennas used on NASA's Deep Space Network, which have been designed to minimize all noise sources, several studies have typically reported measured noise temperatures between 2 and 3 K (at approx. 8.45 GHz, antenna pointing at zenith), attributed to the struts and other unknown effects (see for example [1] and [2]). With this in mind, an effort has recently been conducted to determine optimal strut shapes to reduce the associated noise contribution [3].

Prata, A., Jr.↗
NASA NTRS2012

Retrofits Convert Gas Vehicles into Hybrids

Successful space missions can rarely be attributed to a single thing. Rather, they are the result of a system of systems: integrated elements functioning effectively in their individual roles and together with related components, then those systems interacting with and supporting other systems to form a collaborative whole - from the spacecraft itself to the engineering and research teams that design and build it. An example is found in spacecraft power systems. Unlike a gas-powered car or a battery-powered laptop, most spacecraft are powered by multiple energy sources - such as photovoltaic panels, fuel cells, and batteries - working in tandem to ensure the spacecraft functions throughout the course of a mission. As with any system, the appropriate combination of elements and the method of their management are key to high performance and efficiency. One initiative at Glenn Research Center, the Hybrid Power Management (HPM) program, focused on joining new and mature technologies for optimal power systems applications in space and on Earth, with the goal not only to develop ultra-efficient space power systems, but to advance HPM to address global energy issues. The HPM program emerged from Glenn s long history of electric vehicle research dating back to the 1970s, including the NASA Hybrid Electric Transit Bus (HETB) project in the 1990s, which was the largest vehicle to use supercapacitor energy storage.

Source record↗
DOE OSTI2020

Pushing Green: Leveraging Home Energy Score to Promote Deep-Energy Retrofits in Portland, Oregon

In the United States, 39% of total energy is consumed by the building sector, 20% of which is attributed to residential buildings. Older homes, built before 1992 when the U.S. Department of Energy’s (DOE) Building Energy Codes Program was established, represent approximately 68% of residential building stock in the country and often have significant air leakage, inadequate insulation and inefficient heating & cooling systems. These older homes have long been the elephant in the room: how can programs effectively increase efficiency in all of the homes in need? Developed by DOE, the Home Energy Score was established to provide homeowners, buyers, and renters a comparable score measuring a home's energy use. Much like the MPG rating of automobiles, the Home Energy Score provides an overview of a residential building’s energy efficiency. In 2016, the City of Portland passed an ordinance requiring all residential properties to receive a Home Energy Score before being listed for sale, a mandate that was implemented January 1, 2018. Since 2018, more than 22,000 homes throughout the Portland Metro area have received Home Energy Scores (amounting to over 10% of Portland's single-family homes). This paper explores the sample of Home Energy Scores throughout Portland, including at the neighborhood level, identifies trends in efficiency measures, describes how the data has been used to date and proposes ways program administrators can use the Home Energy Score to increase the impact of energy efficiency programs on a city-scale.

Antonopoulos, Chrissi A.↗
DOE OSTI2022

Developing a Composite Vacuum Insulated Panel (VIP) Insulation/Vinyl Siding Composite Technology for Retrofitting Residential Walls

This paper reports on a project that has attempted to seize on an opportunity to take a giant leap forward in commercializing a technology that would address a key opportunity to achieve energy savings in the existing residential housing stock. It is typically very difficult to increase the R-value of the walls in existing residential housing as doing so from the inside is disruptive and there have not been good solutions to increase thermal envelope performance from the exterior through adding continuous insulation due to the additional work required to fit existing architectural features to the new wall thickness and to reclad the façade. A high thermal resistivity or R-value per inch product that can be used in these applications offers an excellent solution.This paper summarizes a three-year research project to a produce vacuum insulated panel (VIP)/vinyl siding that would have sufficient R-value to meet the continuous insulation requirements of the 2018 International Energy Conservation Code (IECC, 2018) in all climate zones and has a much thinner profile that will facilitate its application to existing residential homes without the need for expensive retrimming of the architectural details. The paper will supply information on the development of the technology, its thermal modelling, testing, voice of user sessions to solicit input from architects, designers, manufacturers, contractors, and installers, and a techno-economic analysis to gauge its competitiveness with existing product options.

Desjarlais, Andre Omer↗
DOE OSTI2022

The Environmental Impact of Deep Energy Retrofits in Residential Construction

Almost two thirds of the residential homes in the U.S. were constructed before the Department of Energy implemented energy conservation measures that were later formalized in the building codes. To reduce energy consumption and carbon emissions from the built environment, improvement to the existing housing stock is a prerequisite. However, improvements that lower energy consumption address carbon emissions related to heating, cooling and plug loads but not the embodied carbon of the building materials that also contribute to global carbon emissions. As the enclosure is made more efficient a larger portion of total carbon emissions is embodied carbon from the building materials. To mitigate carbon emissions, a holistic approach is required so that any improvement to the home results in a net reduction in carbon emissions. To understand the overall environmental impact of building enclosure improvements, the embodied and operational carbon emissions are calculated in this investigation and compared to the overall energy savings associated with enclosure improvements. The energy savings together with a reduction in operational carbon emissions are calculated using a novel building envelope metric. The net carbon emissions are then determined before and after the energy improvement measures. This approach allows or enables architects and builders to select designs that result in maximizing the overall reduction in energy and carbon emissions.

Aldykiewicz Jr, Antonio↗