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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 883 records · Page 49
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

A Model for Joint Probabilistic Forecast of Solar Photovoltaic Power and Outdoor Temperature

In this paper, a stochastic model is proposed for a joint statistical description of solar photovoltaic (PV) power and outdoor temperature. The underlying correlation emerges from solar irradiance that is responsible in part for both the variability in solar PV power and temperature. The proposed model can be used to capture the uncertainty in solar PV power and its correlation with the electric power consumption of thermostatically controlled loads. First, a model for solar PV power that explicitly incorporates the stochasticity due to clouds via a regime-switching process between the three classes of sunny , overcast and partly cloudy is proposed. Then, the relationship between temperature and solar power is postulated using a second-order Volterra model. This joint modeling is leveraged to develop a joint probabilistic forecasting method for solar PV power and temperature. Real-world datasets that include solar PV power and temperature measurements in California are analyzed and the effectiveness of the joint model in providing probabilistic forecasts is verified. The proposed forecasting methodology outperforms several reference methods thus portraying that the underlying correlation between temperature and solar PV power is well defined and only requires a simple lower-complexity sampling space.

14 SOLAR ENERGY↗
DOE OSTI2012

Managing the Drivers of Air Flow and Water Vapor Transport in Existing Single Family Homes (Revised)

This document focuses on managing the driving forces which move air and moisture across the building envelope. While other previously published Measure Guidelines focus on elimination of air pathways, the ultimate goal of this Measure Guideline is to manage drivers which cause air flow and water vapor transport across the building envelope (and also within the home), control air infiltration,keep relative humidity (RH) within acceptable limits, avoid combustion safety problems, improve occupant comfort, and reduce house energy use.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2012

SunShot Prize: America's Most Affordable Rooftop Solar: A Competition To Spur Low-Cost Rooftop Solar Installations Across The Nation (Fact Sheet)

The SunShot Prize encourages novel public-private partnerships, original business models, and innovative approaches to installing clean, renewable solar energy. The sustainable business strategies developed by participants will provide transferable lessons that can be applied nationwide to hasten America's transition to affordable clean energy in a post-subsidy market.

14 SOLAR ENERGY↗
DOE OSTI2012

Laboratory Testing of Aerosol for Enclosure Air Sealing

Space conditioning energy use can be significantly reduced by addressing uncontrolled infiltration and exfiltration through the envelope of a building. A process for improving the air tightness of a building envelope by sealing shell leaks with an aerosol sealing technology is presented. Both retrofit and new construction applications are possible through applying this process either in attics and crawlspaces or during rough-in stage.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2012

Field Evaluation of Highly Insulating Windows in the Lab Homes: Winter Experiment

This field evaluation of highly insulating windows was undertaken in a matched pair of 'Lab Homes' located on the Pacific Northwest National Laboratory (PNNL) campus during the 2012 winter heating season. Improving the insulation and solar heat gain characteristics of a home's windows has the potential to significantly improve the home's building envelope and overall thermal performance by reducing heat loss (in the winter), and cooling loss and solar heat gain (in the summer) through the windows. A high quality installation and/or window retrofit will also minimize or reduce air leakage through the window cavity and thus also contribute to reduced heat loss in the winter and cooling loss in the summer. These improvements all contribute to decreasing overall annual home energy use. Occupant comfort (non-quantifiable) can also be increased by minimizing or eliminating the cold 'draft' (temperature) many residents experience at or near window surfaces that are at a noticeably lower temperature than the room air temperature. Lastly, although not measured in this experiment, highly insulating windows (triple-pane in this experiment) also have the potential to significantly reduce the noise transmittance through windows compared to standard double-pane windows. The metered data taken in the Lab Homes and data analysis presented here represent 70 days of data taken during the 2012 heating season. As such, the savings from highly insulating windows in the experimental home (Lab Home B) compared to the standard double-pane clear glass windows in the baseline home (Lab Home A) are only a portion of the energy savings expected from a year-long experiment that would include a cooling season. The cooling season experiment will take place in the homes in the summer of 2012, and results of that experiment will be reported in a subsequent report available to all stakeholders.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2013

NREL Recommends Ways to Cut Building Energy Costs in Half (Fact Sheet)

Building designers and operators could cut energy use by 50% in large office buildings, hospitals, schools, and a variety of stores -- including groceries, general merchandise outlets, and retail outlets -- by following the recommendations of NREL researchers. The innovative energy-saving recommendations are contained in technical support documents and Advanced Energy Design Guides compiled by NREL.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2013

Multifamily Individual Heating and Ventilation Systems, Lawrence, Massachusetts (Fact Sheet)

The conversion of an older Massachusetts building into condominiums illustrates a safe, durable, and cost-effective solution for heating and ventilation systems that can potentially benefit millions of multifamily buildings. Merrimack Valley Habitat for Humanity (MVHfH) partnered with U.S. Department of Energy Building America team Building Science Corporation (BSC) to provide high performance affordable housing for 10 families in the retrofit of an existing mass masonry building (a former convent). The original ventilation design for the project was provided by a local engineer and consisted of a single large heat recovery ventilator (HRV) located in a mechanical room in the basement with a centralized duct system providing supply air to the main living space and exhausting stale air from the single bathroom in each apartment. This design was deemed to be far too costly to install and operate for several reasons: the large central HRV was oversized and the specified flows to each apartment were much higher than the ASHRAE 62.2 rate; an extensive system of ductwork, smoke and fire dampers, and duct chases were specified; ductwork required a significant area of dropped ceilings; and the system lacked individual ventilation control in the apartments.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2013

Foundation Design Handbook

The purpose of this handbook is to provide information that will enable designers, builders, and homeowners to understand foundation design problems and solutions. The foundation of a house is a somewhat invisible and sometimes ignored component of the building. It is increasingly evident, however, that attention to good foundation design and construction has significant benefits to the homeowner and the builder, and can avoid some serious future problems. Good foundation design and construction practice means not only insulating to save energy, but also providing effective structural design as well as moisture, termite, and radon control techniques where appropriate.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2015

Highly Automated Module Production Incorporating Advanced Light Management

The objective was to enable a high volume, cost effective solution for increasing the amount of light captured by PV modules through utilization of an advanced Light Re-directing Film and to follow a phased approach to develop and implement this new technology in order to achieve an expected power gain of up to 12 watts per module. Full size PV modules were manufactured using a new Light Redirecting Film (LRF) material applied to two different areas of PV modules in order to increase the amount of light captured by the modules. One configuration involved applying thin strips of LRF film over the tabbing ribbon on the cells in order to redirect the light that is normally absorbed by the tabbing ribbon to the active areas of the cells. A second configuration involved applying thin strips of LRF film over the white spaces between cells within a module in order to capture some of the light that is normally reflected from the white areas back through the front glass of the modules. Significant power increases of 1.4% (3.9 watts) and 1.0% (3.2 watts), respectively, compared to standard PV modules were measured under standard test conditions. The performance of PV modules with LRF applied to the tabbing ribbon was modeled. The results showed that the power increase provided by LRF depended greatly on the angle of incident light with the optimum performance only occurring when the light was within a narrow range of being perpendicular to the solar module. The modeling showed that most of the performance gain would be lost when the angle of incident light was greater than 28 degrees off axis. This effect made the orientation of modules with LRF applied to tabbing ribbons very important as modules mounted in “portrait” mode were predicted to provide little to no power gain from LRF under real world conditions. Based on these results, modules with LRF on tabbing ribbons would have to be mounted in “landscape” mode to realize a performance advantage. In addition, modeling showed that under diffuse lighting conditions such as when the sky is overcast, there would be no significant performance advantage for modules with LRF. Modules were sent to an outside contractor to measure the power performance under different angles of incident light in order to validate the modeling results. The measured data agreed very well with the modeling predictions and showed that the power gain for modules with LRF applied to tabbing ribbons was completely lost at an angle of 25 degrees off of perpendicular. At even larger angles, the power was lower than standard modules. From 35 degrees to 55 degrees off axis, the power loss was about 1.4% or equal to the power gain at the optimum condition of perfectly on-axis light.

14 SOLAR ENERGY↗
DOE OSTI2013

Evaluation of CNT Energy Savers Retrofit Packages Implemented in Multifamily Buildings

This evaluation explored the feasibility of designing prescriptive retrofit measure packages for typical Chicago region multifamily buildings in order to achieve 25%-30% source energy savings through the study of three case studies. There is an urgent need to scale up energy efficiency retrofitting of Chicago's multifamily buildings in order to address rising energy costs and a rapidly depleting rental stock. Aimed at retrofit program administrators and building science professionals, this research project investigates the possibility of using prescriptive retrofit packages as a time- and resource-effective approach to the process of retrofitting multifamily buildings.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2016

Modular Zero Energy. BrightBuilt Home

Kaplan Thompson Architects (KTA) has specialized in sustainable, energy-efficient buildings, and they have designed several custom, zero-energy homes in New England. These zero-energy projects have generally been high-end, custom homes with budgets that could accommodate advanced energy systems. In an attempt to make zero energy homes more affordable and accessible to a larger demographic, KTA explored modular construction as way to provide high-quality homes at lower costs. In the mid-2013, KTA formalized this concept when they launched BrightBuilt Home (BBH). The BBH mission is to offer a line of architect-designed, high-performance homes that are priced to offer substantial savings off the lifetime cost of a typical home and can be delivered in less time. For the past two years, CARB has worked with BBH and Keiser Homes (the primary modular manufacturer for BBH) to discuss challenges related to wall systems, HVAC, and quality control. In Spring of 2014, CARB and BBH began looking in detail on a home to be built in Lincolnville, ME by Black Bros. Builders. This report details the solution package specified for this modular plan and the challenges that arose during the project.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2013

Evaluation of CNT Energy Savers Retrofit Packages Implemented in Multifamily Buildings

This evaluation explored the feasibility of designing prescriptive retrofit measure packages for typical Chicago region multifamily buildings in order to achieve 25%-30% source energy savings through the study of three case studies. There is an urgent need to scale up energy efficiency retrofitting of Chicago's multifamily buildings in order to address rising energy costs and a rapidly depletingrental stock. Aimed at retrofit program administrators and building science professionals, this research project investigates the possibility of using prescriptive retrofit packages as a time- and resource-effective approach to the process of retrofitting multifamily buildings.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

Small Business Voucher CRADA Report: Natural Gas Powered HVAC System for Commercial and Residential Buildings

Be Power Tech is commercializing BeCool, the first integrated electricity-producing heating, ventilation, and air conditioning (HVAC) system using a non-vapor compression cycle (VCC), packaged rooftop HVAC unit that also produces base-load electricity, heating, ventilation, and air conditioning. BeCool is a distributed energy resource with energy storage that eliminates the tremendous peak electricity demand associated with commonly used electricity-powered vapor compression air conditioning systems.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2022

Bringing Fault Detection and Diagnostics (FDD) Tools into the Mainstream: Retro Commissioning and Continuous Commissioning of HVAC and Refrigeration Systems

HVAC systems in the commercial building sector consume about 3.4 quads of energy annually. Of all the HVAC systems, packaged rooftop air–conditioning units (RTUs) provide cooling and heating for over 60 percent of the commercial building floorspace (about 90 billion ft2) in the U.S. and they are a significant source of energy consumption and peak demand. All HVAC systems suffer from faults that impact thermal comfort and increase energy consumption. There are several commercially available Automated Fault Detection and Diagnostic (AFDD) tools on the market that can detect and diagnose faults, and if those faults are corrected, can save significant national energy. However, there are multiple market barriers for these tools including lack of independent verification of their performance in the field in terms of their technical capabilities, ease of use and installation.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2019

WRF-UCM CDD (cooling degree days) data

The MATLAB (.mat) files (spatial grids of daily CDD data) are generated by a suit of WRF-UCM simulations over California at 4.5 km resolution (1.5 km resolution over cities) for 5 scenarios

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

Distributed Solar Technoeconomic Agent Characteristics dSTAC

These data files summarize key techno-economic metrics used in the NREL dGen model for modeling adoption of distributed solar by representative residential commercial and industrial entities for each county in the continental United States. As described further below many of the metrics are derived as summaries of outputs from dGen. Specifically each county and sector in these file are summarized as a single agent that is the weighted average of 10 statistically-representative agents weighed by the statistical frequency. The dGen simulation used to derive this dataset was conducted in 2018 using the NREL 2018 Standard Scenario Mid Case assumptions https//www.nrel.gov/docs/fy19osti/71913.pdf.

agent-based modeling↗
NASA NTRS2003

Engine Installation Effects of Four Civil Transport Airplanes: Wallops Flight Facility Study

The National Aeronautics and Space Administration (NASA), Langley Research Center (LaRC), the Environmental Measurement and Modeling Division of the United States Department of Transportation s John A. Volpe National Transportation Systems Center (Volpe), and several other organizations (see Appendix A for a complete list of participating organizations and individuals) conducted a noise measurement study at NASA s Wallops Flight Facility (Wallops) near Chincoteague, Virginia during September 2000. This test was intended to determine engine installation effects on four civil transport airplanes: a Boeing 767-400, a McDonnell-Douglas DC9, a Dassault Falcon 2000, and a Beechcraft King Air. Wallops was chosen for this study because of the relatively low ambient noise of the site and the degree of control over airplane operating procedures enabled by operating over a runway closed to other uses during the test period. Measurements were conducted using a twenty microphone U-shaped array oriented perpendicular to the flight path; microphones were mounted such that ground effects were minimized and low elevation angles were observed.

Fleming, Gregg G.↗
NASA NTRS2015

Behind Start of Take-Off Roll Aircraft Sound Level Directivity Study - Revision 1

The National Aeronautics and Space Administration (NASA), Langley Research Center (LaRC) and the Environmental Measurement and Modeling Division of the Department of Transportation's Volpe National Transportation Systems Center (Volpe) conducted a noise measurement study to examine aircraft sound level directivity patterns behind the start-of-takeoff roll. The study was conducted at Washington Dulles International Airport (IAD) from October 4 through 20, 2004.

Lau, Michael C.↗