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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 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Technology Solutions Case Study: Air-To-Water Heat Pumps with Radiant Delivery in Low Load Homes, Tucson, Arizona and Chico, California

Space conditioning represents nearly 50% of average residential household energy consumption, highlighting the need to identify alternative cost-effective, energy-efficient cooling and heating strategies. As homes are better built, there is an increasing need for strategies that are particularly well suited for high performance, low load homes. ARBI researchers worked with two test homes in hot-dry climates to evaluate the in-situ performance of air-to-water heat pump (AWHP) systems, an energy efficient space conditioning solution designed to cost-effectively provide comfort in homes with efficient, safe, and durable operation. Both systems were fully instrumented and have been monitored over one year to capture complete performance data over the cooling and heating seasons. Results are used to quantify energy savings, cost-effectiveness, and system performance using different operating modes and strategies. This strategy is most effective in tight, insulated homes with high levels of thermal mass (i.e. exposed slab floors).

air conditioning↗
DOE OSTI2013

Air-to-Water Heat Pumps With Radiant Delivery in Low-Load Homes

Space conditioning represents nearly 50% of average residential household energy consumption, highlighting the need to identify alternative cost-effective, energy-efficient cooling and heating strategies. As homes are better built, there is an increasing need for strategies that are particularly well suited for high performance, low load homes. ARBI researchers worked with two test homes in hot-dry climates to evaluate the in-situ performance of air-to-water heat pump (AWHP) systems, an energy efficient space conditioning solution designed to cost-effectively provide comfort in homes with efficient, safe, and durable operation. Two monitoring projects of test houses in hot-dry climates were initiated in 2010 to test this system. Both systems were fully instrumented and have been monitored over one year to capture complete performance data over the cooling and heating seasons. Results are used to quantify energy savings, cost-effectiveness, and system performance using different operating modes and strategies. A calibrated TRNSYS model was developed and used to evaluate performance in various climate regions. This strategy is most effective in tight, insulated homes with high levels of thermal mass (i.e. exposed slab floors).

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

Case Study for the ARRA-funded Ground Source Heat Pump (GSHP) Demonstration at Wilders Grove Solid Waste Service Center in Raleigh, NC

High initial costs and lack of public awareness of ground-source heat pump (GSHP) technology are the two major barriers preventing rapid deployment of this energy-saving technology in the United States. Under the American Recovery and Reinvestment Act (ARRA), 26 GSHP projects have been competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This paper highlights the findings of a case study of one of the ARRA-funded GSHP demonstration projects, a distributed GSHP system for providing all the space conditioning, outdoor air ventilation, and 100% domestic hot water to the Wilders Grove Solid Waste Service Center of City of Raleigh, North Carolina. This case study is based on the analysis of measured performance data, construction costs, and simulations of the energy consumption of conventional central heating, ventilation, and air-conditioning (HVAC) systems providing the same level of space conditioning and outdoor air ventilation as the demonstrated GSHP system. The evaluated performance metrics include the energy efficiency of the heat pump equipment and the overall GSHP system, pumping performance, energy savings, carbon emission reductions, and cost-effectiveness of the GSHP system compared with conventional HVAC systems. This case study also identified opportunities for reducing uncertainties in the performance evaluation and improving the operational efficiency of the demonstrated GSHP system.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2014

Field Study of Performance, Comfort, and Sizing of Two Variable-Speed Heat Pumps Installed in a Single 2-Story Residence

With the recent advancements in the application of variable-speed (VS) compressors to residential HVAC systems, opportunities are now available to size heat pumps (HPs) to more effectively meet heating and cooling loads in many of the climate zones in the US with limited use of inefficient resistance heat. This is in contrast to sizing guidance for traditional single-speed HPs that limits the ability to oversize with regard to cooling loads, because of risks of poor dehumidification during the cooling season and increased cycling losses. VS-drive HPs can often run at 30-40% of their rated cooling capacity to reduce cycling losses, and can adjust fan speed to provide better indoor humidity control. Detailed air-side performance data was collected on two VS-drive heat pumps installed in a single unoccupied research house in Knoxville, TN, a mixed-humid climate. One system provided space conditioning for the upstairs, while the other unit provided space conditioning for the downstairs. Occupancy was simulated by operating the lights, shower, appliances, other plug loads, etc. to simulate the sensible and latent loads imposed on the building space by internal electric loads and human occupants according to the Building America Research Benchmark (2008). The seasonal efficiency and energy use of the units are calculated. Annual energy use is compared to that of the single speed minimum efficiency HPs tested in the same house previously. Sizing of the units relative to the measured building load and manual J design load calculations is examined. The impact of the unit sizing with regards to indoor comfort is also evaluated.

Munk, Jeffrey D↗
NASA NTRS2000

Approaches in the determination of plant nutrient uptake and distribution in space flight conditions

The effective growth and development of vascular plants rely on the adequate availability of water and nutrients. Inefficiency in either the initial absorption, transportation, or distribution of these elements are factors which impinge on plant structure and metabolic integrity. The potential effect of space flight and microgravity conditions on the efficiency of these processes is unclear. Limitations in the available quantity of space-grown plant material and the sensitivity of routine analytical techniques have made an evaluation of these processes impractical. However, the recent introduction of new plant cultivating methodologies supporting the application of radionuclide elements and subsequent autoradiography techniques provides a highly sensitive investigative approach amenable to space flight studies. Experiments involving the use of gel based 'nutrient packs' and the radionuclides calcium-45 and iron-59 were conducted on the Shuttle mission STS-94. Uptake rates of the radionuclides between ground and flight plant material appeared comparable.

manned↗
NASA NTRS1998

Approaches in the Determination of Plant Nutrient Uptake and Distribution in Space Flight Conditions

The effective growth and development of vascular plants rely on the adequate availability of water and nutrients. Inefficiency in either the initial absorption, transportation, or distribution of these elements are factors which may impinge on plant structure and metabolic integrity. The potential effect of space flight and microgravity conditions on the efficiency of these processes is unclear. Limitations in the available quantity of space-grown plant material and the sensitivity of routine analytical techniques have made an evaluation of these processes impractical. However, the recent introduction of new plant cultivating methodologies supporting the application of radionuclide elements and subsequent autoradiography techniques provides a highly sensitive investigative approach amenable to space flight studies. Experiments involving the use of gel based 'nutrient packs' and the nuclides Ca45 and Fe59 were conducted on the Shuttle mission STS-94. Uptake rates of the radionuclides between ground and flight plant material appeared comparable.

Heyenga, A. G.↗
NASA NTRS1998

Assessment Regarding Impact of Atmospheric Conditions on Space Shuttle Launch Delays

The atmospheric environment definition has played a key role in the development and operation of the NASA Space Shuttle as it has in other NASA Space Vehicle Programs. The objective of any definition of natural environment design requirements for a space vehicle development is to insure that the vehicle will perform safely and in a timely manner relative to the mission(s) for which the vehicle is being developed. The NASA Space Shuttle has enjoyed the longest tenure of any Space Vehicle from an operational standpoint. As such, it has provided a wealth of information on many engineering aspects of a Space Vehicle plus the influence of the atmosphere on operational endeavors. The atmospheric environment associated with the NASA Space Shuttle launches at the NASA Kennedy Space Center in Florida has been reviewed and studied over the entire NASA Space Shuttle flight history. The results of the analysis of atmospheric environment related launch delays relative to other sources of launch delays has been assessed. This paper will provide a summary of those conditions as well as mission analysis examples focused on atmospheric constraints for launch. Atmospheric conditions associated with NASA Space Shuttle launch delays will be presented to provide a reference as to the type conditions experienced which have mainly caused the delays.

Johnson D. L.↗
DOE OSTI2013

Reducing Thermal Losses and Gains With Buried and Encapsulated Ducts in Hot-Humid Climates

Thermal losses and gains from ductwork installed in unconditioned spaces—such as attics, crawl spaces, and garages—can contribute significantly to the overall heating and cooling loads of single-family residential buildings, with estimated duct losses ranging from 10%–45 %. The impact is particularly severe in hot climates where air conditioning dominates and extensive duct systems are typically located in hot attics. The duct system inefficiencies are greatest at peak demand conditions when the attic is hottest and run times are the highest. The thermal losses and gains at the three single-story houses in Florida monitored in this study accounted for 15%–35% of the annual pre-retrofit heating and cooling energy use and 6%–25% of the total pre-retrofit annual utility bill. Even though a number of existing methods can effectively move ducts into the conditioned space, they are not currently being widely implemented. Physically locating the ducts within the conditioned space is most often applicable only to new construction projects and requires planning during design. Attics can be insulated at the roof deck with closed-cell polyurethane foam (ccSPF) to reduce duct losses and infiltration rates, but this method has high up-front costs and the potential to increase loads on the building enclosure. In hot-dry climates, attic duct systems can be buried under loose-fill insulation at a significantly lower cost to reduce thermal loads. In hot-humid climates, however, condensation on the duct jacket can occur when the humidity in the attic is high.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2014

Impact of HPWH Placement on Water Heating Performance and Effect on Air Temperature in its Immediate Environ

Heat pump water heaters (HPWHs) extract thermal energy from their surroundings to make hot water with two to three times better efficiency than conventional electric resistance water heaters. But, how much does HPWH placement influence its performance? This paper summarizes performance metrics of two 189 L (50 gallon) HPWHs one placed within conditioned space, and the other placed in the garage of two separate, but similar research houses each delivering approximately 208 L/d (55 gallons/d) hot water under simulated occupancy conditions. Both houses had space conditioning set points of 24.4 C (76 F) and 21.7 C (71 F) in Summer and in Winter, respectively, and hot water temperature setting of 48.9 C (120 F). Performance metrics are compared on a monthly basis for 2011.

Munk, Jeffrey D↗
NASA NTRS1975

Preservation of human performance capacity under prolonged space flight conditions

Prophylactic measures directed toward preservation of health and maintenance of the performance ability of a man during prolonged space flight stress center on the selection of optimum work and rest cycles, physical exercises, the use of pharmacological agents, conditioning of the cardiovascular apparatus, etc. A specially selected set of hormone and pharmacological preparations is recommended to stimulate hemopoiesis.

Yeremin, A. V.↗
DOE OSTI2013

Comparison of Advanced Residential Water Heating Technologies in the United States

In this study, gas storage, gas tankless, condensing, electric storage, heat pump, and solar water heaters were simulated in several different climates across the United States, installed in both conditioned and unconditioned space and subjected to several different draw profiles. While many pre-existing models were used, new models of condensing and heat pump water heaters were created specifically for this work. In each case modeled, the whole house was simulated along with the water heater to capture any interactions between the water heater and the space conditioning equipment.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
NASA NTRS1997

Assessment of MIR orbital station external condition using Space Shuttle photographic and video imagery

The results of photographic and video surveys conducted on the Mir space station are reported. The observations were performed in order to quantitatively and qualitatively assess the effects of the external deposition and contamination, surface degradation, dynamic events, and micrometeoroid and orbital debris impacts. The lessons learned from Mir imagery observations can be applied to the International Space Station program. The photographic and video data confirm the general good condition of the external surfaces of Mir.

Gaunce, M. T.↗
NASA NTRS2019

ExMC Approach to Pharmaceutical Stability Research: An Overview

Goals of Stability Studies: Identify medications that are stable under real and simulated space conditions, especially deep space radiation; Identify medications that are potent and safe after their expiration dates; Ultimately provide a safe and effective formulary for exploratory spaceflight missions. ExMC: Exploration Medical Capabilities.

Cory, Wendy↗
DOE OSTI2013

Short-Term Monitoring Results for Advanced New Construction Test House—Roseville, California

A builder (K. Hovnanian® Homes®), design consultant, and trades collaborated to identify a systems integrated measures package for a 2,253-ft 2 slab-on-grade ranch house to achieve a modeled energy savings of 60% with respect to the Building America House Simulation Protocols, while minimizing construction costs and without requiring changes to the drawing that would impact local code or zoning approval. The key building improvements were applying R-10 insulation to the slab edge, increasing exterior wall cavity insulation from R-13 to R-15, and increasing attic insulation from R-30 to R-38. Also, the air handling unit was relocated from the attic to conditioned space, and ductwork was relocated along the attic floor with an insulated bulkhead built above it. Short-term testing results showed that duct air leakage was low due to short duct runs and the placement of ductwork in conditioned space. However, during commissioning, the lack of access for servicing the ductwork and dampers in the bulkhead area prevented retroactive balancing of individual branches, resulting in significant differences between specified and measured airflow values for some duct runs. Thermal imaging results performed on the house when operating in both heating and cooling modes validated historic stratification issues of ceiling supply registers with high supply air temperatures. Long-term monitoring results will be detailed in a future report.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2020

Tracer gas test in Net-Zero Energy Residential Test Facility

The Net-Zero Energy Residential Test Facility (NZERTF) at NIST was built in 2012 to support the development and adoption of cost-effective net-zero energy designs, technologies, and construction methods. It is two-story, and has four bedrooms, three bathrooms, and an open living room, dining room, and kitchen space. The NZERTF also has a basement and attic, both located within the conditioned space because the thermal and air-moisture barriers encompass the basement walls and attic roof. Transfer grilles link the living spaces to these two zones. The central heating and cooling system includes an air-toair heat pump, which delivers air to the basement, first and second floors. The heat pump has a cooling capacity of 7.6 kW and a heating capacity of 7.8 kW. The indoor unit is in the basement and ductwork runs along the basement ceiling. A balanced heat recovery ventilator (HRV) is installed in the basement and has its own dedicated ductwork. The HRV supplies 47 L/s of outdoor air to the house, with supplies on the first floor (in the kitchen/dining area) and in each of the three second-floor bedrooms. Air from the first-floor bathroom and both second-floor bathrooms is returned to the HRV before being exhausted, though the HRV was turned off during the tests. The house also has a range hood exhaust and a clothes dryer exhaust, both of which were turned off for the tests. The temperature of the house was measured and the operation of the space conditioning system, including its recirculating air distribution fan, were controlled by a commercially available thermostat.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2024

Overview of Building Electrification Technologies and Market Opportunities

This report provides an overview of building electrification drivers and select building electrification technologies and their markets and performance. Covered topics: Building Electrification Drivers and Context; Heat Pumps for Space Conditioning; Heat Pump Market Opportunities; Life Cycle GHG Emissions Impacts of Heat Pump Space Conditioning Technologies; Heat Pump Water Heaters; Electrification of Gas Loads: Commercial and Residential; Residential Panel Capacity; Electric Vehicle Impacts and Connections to Buildings; and Building Envelope Improvements and Thermal Energy Storage (TES) Opportunities.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2015

Technology Solutions Case Study: Long-Term Monitoring of Mini-Split Ductless Heat Pumps in the Northeast, Devens and Easthampton, Massachusetts

Transformations, Inc., has extensive experience building high-performance homes - production and custom - in a variety of Massachusetts locations and uses mini-split heat pumps (MSHPs) for space conditioning in most of its homes. The use of MSHPs for simplified space-conditioning distribution provides significant first-cost savings, which offsets the increased investment in the building enclosure. In this project, the U.S. Department of Energy Building America team Building Science Corporation evaluated the long-term performance of MSHPs in 8 homes during a period of 3 years. The work examined electrical use of MSHPs, distributions of interior temperatures and humidity when using simplified (two-point) heating systems in high-performance housing, and the impact of open-door/closed-door status on temperature distributions.

BSC↗
DOE OSTI2012

Exergy analysis and operational efficiency of a horizontal ground-source heat pump system operated in a low-energy test house simulated occupancy conditions

This paper presents detailed analysis of a water to water ground source heat pump (WW-GSHP) to provide all the hot water needs in a 345 m 2 house located in DOE climate zone 4 (mixed-humid). The protocol for hot water use is based on the Building America Research Benchmark Definition (Hendron 2008; Hendron and Engebrecht 2010) which aims to capture the living habits of the average American household and its impact on energy consumption. The entire house was operated under simulated occupancy conditions. Detailed energy and exergy analysis provides a complete set of information on system efficiency and sources of irreversibility, the main cause of wasted energy. The WW-GSHP was sized at 5.275 kW (1.5-ton) for this house and supplied hot water to a 303 L (80 gal) water storage tank. The WW-GSHP shared the same ground loop with a 7.56 kW (2.1-ton) water to air ground source heat pump (WA-GSHP) which provided space conditioning needs to the entire house. Data, analyses, and measures of performance for the WW-GSHP in this paper complements the results of the WA-GSHP published in this journal (Ally, Munk et al. 2012). Understanding the performance of GSHPs is vital if the ground is to be used as a viable renewable energy resource.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗