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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 469 records · Page 26

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DOE OSTI2014

Solar Panels on Hudson County Facilities

This project involved the installation of an 83 kW grid-connected photovoltaic system tied into the energy management system of Hudson County's new 60,000 square foot Emergency Operations and Command Center and staff offices. Other renewable energy features of the building include a 15 kW wind turbine, geothermal heating and cooling, natural daylighting, natural ventilation, gray water plumbing system and a green roof. The County intends to seek Silver LEED certification for the facility.

Photovoltaic↗

DOE OSTI2013

Porflow Modeling Supporting the FY13 Saltstone Special Analysis

PORFLOW modeling supporting the concurrent Saltstone FY13 Special Analysis (SA) is described in this report. The present simulations are based on the 2009 Performance Assessment and subsequent modeling to support a response to NRC Request for Additional Information PA-8. Notable changes to the baseline PA-8 model include revised degradation of cementitious materials and associated hydraulic properties, inclusion of floor joints and roof support columns in model representations, and a revised Tc-99 shrinking-core model to implement combined redox and solubility controls. Also presented are new and further justifications for key model assumptions, and verification test cases for selected model attributes. Results are presented for the nominal value simulation case, a flow sensitivity parametric study, and Tc-99 transport sensitivity cases. Further discussion of PORFLOW model setup and simulation results is presented in the Saltstone FY13 SA, including dose results.

Cementitious Materials↗

DOE OSTI2014

Moisture Risk in Unvented Attics Due to Air Leakage Paths

IBACOS completed an initial analysis of moisture damage potential in an unvented attic insulated with closed-cell spray polyurethane foam. To complete this analysis, the research team collected field data, used computational fluid dynamics to quantify the airflow rates through individual airflow (crack) paths, simulated hourly flow rates through the leakage paths with CONTAM software, correlated the CONTAM flow rates with indoor humidity ratios from Building Energy Optimization software, and used Warme und Feuchte instationar Pro two-dimensional modeling to determine the moisture content of the building materials surrounding the cracks. Given the number of simplifying assumptions and numerical models associated with this analysis, the results indicate that localized damage due to high moisture content of the roof sheathing is possible under very low airflow rates. Reducing the number of assumptions and approximations through field studies and laboratory experiments would be valuable to understand the real-world moisture damage potential in unvented attics.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2014

Port of Galveston Solar Energy Project

This study on the performance characteristics of existing solar technologies in a maritime environment was funded by an award given to The Port of Galveston (POG) from the U.S. Department of Energy (DOE). The study includes research performed by The Center for Advanced Materials at the University of Houston (UH). The UH researchers examined how solar cell efficiencies and life spans can be improved by examining the performance of a variety of antireflective (AR) coatings mounted on the top of one of the POG’s Cruise Terminals. Supplemental supporting research was performed at the UH laboratories. An educational Kiosk was constructed with a 55” display screen providing information about solar energy, the research work UH performed at POG and real time data from the solar panels located on the roof of the Cruise Terminal. The Houston Advanced Research Center (HARC) managed the project.

14 SOLAR ENERGY↗

DOE OSTI2014

Sunnyvale Marine Climate Deep Retrofit

The Alliance for Residential Building Innovation (ARBI) and Allen Gilliland of One Sky Homes collaborated on a marine climate retrofit project designed to meet both Passive House (PH) and Building America (BA) program standards. The scope included sealing, installing wall, roof and floor insulation (previously lacking), replacing windows, upgrading the heating and cooling system, and installing.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2015

Interaction of Unvented Attics With Living Space in Three Northeast Homes

Unvented roof assemblies are becoming common in North American construction. It is estimated that over 100,000 have been constructed since 1995 (Schumacher 2007). According to RECS 2011, more than 30% of homes with attics can be found in the very cold/cold climate areas, which equals about 10.4 million housing units. The magnitude of these numbers emphases the significance of properly understanding how the attic conditions vary with respect to the conditioned space below.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2012

Keeping Energy Savings in the LOOP

Mesa Lane Partners (MLP) partnered with the U.S. Department of Energy (DOE) to develop and implement solutions to a build a new, low-energy mixed-use building that consumes at least 50% less energy than requirements set by Energy Standard 90.1-2007 of the American Society of Heating, Refrigerating, and Air-conditioning Engineers (ASHRAE), the American National Standards Institute (ANSI), and the Illuminating Engineering Society of America (IESNA), as part of DOE’s Commercial Building Partnerships (CBP)3 Program. Lawrence Berkeley National Laboratory (LBNL) provided technical expertise in support of this DOE program. The privately developed 46,000-square-foot LOOP project, which is intended to provide affordable off-campus student housing in an underserved community next to University of California at Santa Barbara, will contain more than 7,000 square feet of retail space, a roof deck, an event space, a gym, and 48 apartments. The project developer, MLP, is aiming to exceed CBP requirement, targeting energy consumption that is at least 65% less than that required by the standard. If the LOOP meets this goal, it is expected to achieve Leadership in Energy and Environmental Design (LEED) Gold certification. To meet this goal, the project design incorporates a variety of energy efficiency measures (EEMs) that address the needs of the multiple use types that the project will house.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2015

Velocity field calculation for non-orthogonal numerical grids

Computational grids containing cell faces that do not align with an orthogonal (e.g. Cartesian, cylindrical) coordinate system are routinely encountered in porous-medium numerical simulations. Such grids are referred to in this study as non-orthogonal grids because some cell faces are not orthogonal to a coordinate system plane (e.g. xy, yz or xz plane in Cartesian coordinates). Non-orthogonal grids are routinely encountered at the Savannah River Site in porous-medium flow simulations for Performance Assessments and groundwater flow modeling. Examples include grid lines that conform to the sloping roof of a waste tank or disposal unit in a 2D Performance Assessment simulation, and grid surfaces that conform to undulating stratigraphic surfaces in a 3D groundwater flow model. Particle tracking is routinely performed after a porous-medium numerical flow simulation to better understand the dynamics of the flow field and/or as an approximate indication of the trajectory and timing of advective solute transport. Particle tracks are computed by integrating the velocity field from cell to cell starting from designated seed (starting) positions. An accurate velocity field is required to attain accurate particle tracks. However, many numerical simulation codes report only the volumetric flowrate (e.g. PORFLOW) and/or flux (flowrate divided by area) crossing cell faces. For an orthogonal grid, the normal flux at a cell face is a component of the Darcy velocity vector in the coordinate system, and the pore velocity for particle tracking is attained by dividing by water content. For a non-orthogonal grid, the flux normal to a cell face that lies outside a coordinate plane is not a true component of velocity with respect to the coordinate system. Nonetheless, normal fluxes are often taken as Darcy velocity components, either naively or with accepted approximation. To enable accurate particle tracking or otherwise present an accurate depiction of the velocity field for a non-orthogonal grid, Darcy velocity components are rigorously derived in this study from normal fluxes to cell faces, which are assumed to be provided by or readily computed from porous-medium simulation code output. The normal fluxes are presumed to satisfy mass balances for every computational cell, and if so, the derived velocity fields are consistent with these mass balances. Derivations are provided for general two-dimensional quadrilateral and three-dimensional hexagonal systems, and for the commonly encountered special cases of perfectly vertical side faces in 2D and 3D and a rectangular footprint in 3D.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2015

Minimizing User Burden in Building Energy Analysis

Infrared (IR) imagery can provide valuable data to building energy auditors and the developers of Building Energy Models (BEM). IR by itself is not a panacea to the challenges facing energy auditors and modelers, but when combined with other techniques and Open Studio software, IR can play an important role in the minimization of the burden of creating building energy models and the diagnosing of building energy problems. While IR can be used to detect and quantify many aspects of a building’s thermal and energy performance, in Phase I we focused on a single capability: determining the R value of exterior walls. Two key attributes of using IR methods for R value determination is that IR methods measure the actual, installed performance in-situ – as opposed to relying on manufacturer or handbook values – and they can integrate performance over a wide area and thus can accurately account for thermal bridging and spatial anomalies such as “spotty” insulation installation. There is a trade between user burden and accuracy when using IR to determine a wall’s R value. The least burdensome approach is computing R values from a single IR snapshot. The most burdensome method we considered was to combine IR images with thermocouple and heat flux sensor (HFS) measurements made over the course of several days. The more effort users expend in making the measurements, the more accurate and robust the method becomes. Through a series of field tests at the ThermoAnalytics Inc. (TAI) HQ at Calumet, MI and a simulation of a 1980s era office building in Flagstaff, AZ we investigated methods to compute the R value of exterior walls using data from IR cameras, thermocouples and heat flux sensors. To compute R values the heat flux through the wall, along with temperatures on either side of the wall, must be known, modeled, or estimated – and the temperature difference through the wall should be at least 10 C. If only outdoor IR images are used in the method, the inside ambient air temperature must be estimated, and a simulation model created to predict heat fluxes and the indoor wall temperature. The accuracy of the resulting R value depends on the accuracy of the simulation and the assumptions it employs. Applying thermocouple sensors, either as iButtons or as part of a wireless sensor network, to the walls allows for the acquisition of temperatures over time. The longer the duration of the measurements, the more accurate and robust the method will be. Even with this level of measurement effort, modeling is still required to calculate the heat flux through the wall. The addition of a heat flux sensor alleviates the need for any modeling, and that results in improved accuracy. Driving the accuracy of the methods are several factors that can be quantified. How well are the wall surface temperatures known? Modeling the heat flux through walls requires knowing the details of the surrounding radiant environment and the heat transfer due to convection. How well are these boundary conditions known? Even when the heat flux is measured, error can arise when some of the measured heat is not conducted through the wall but rather goes into the thermal mass of the wall. Thermal mass effects occur when conditions and the heat flux values are fluctuating. A technique that is not robust will suffer in accuracy when these fluctuations occur. The R value determination method must be incorporated into the Open Studio process. In our proposed process, IR images and other measured sensor data are input into a module that would send R value estimates to a building library developed by team member Skidmore, Owings, & Merrill (SOM). This library of parameterized building models would use these R values along with information about the building’s age, type, and location to query the Open Studio BCL to identify the most likely constructions for walls, roof, and windows. Being based on the IMF feature of Energyplus, the SOM building library can quickly produce Energyplus models of buildings based on a limited number of user inputs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2013

Crowder College MARET Center (Final Scientific Technical Report)

Following decades of success in solar energy projects, the Missouri Legislature designated Crowder College in 1992 as the State's renewable energy education center. The resulting Missouri Alternative and Renewable Energy Technology (MARET) Center is recognized internationally for its contributions to the energy field. The mission of the MARET Center is to expand renewable energy throughout the region with education, applied research, and economic development. Educational programs include certification and transfer degrees encompassing green construction, solar thermal energy, solar electricity, and wind. The MARET Center also assists in new product development and other business support services in renewable energy. The Missouri Alternative and Renewable Energy Technology (MARET) Center at Crowder College hopes to eventually develop a 27,500 ft 2 facility as a living laboratory to support solar and other renewable and sustainable energy development through professional degrees, new product development and commercialization, renewable energy business incubation, and consumer education. The primary objective of the current project was to complete Stage One of this building, with solar, wind, and geothermal technologies installed to power its 9,216 ft 2 office, classroom, and research spaces. This MARET Center includes a modular roof structure that permits both solar module mounting and daylighting, PV/thermal hybrid modules pioneered in Crowder Solar Decathlon homes, modular electrical management subsystems; and modular delivery systems for heating and cooling the structure. The MARET Facility will operate as a Net Positive energy building, consistently producing surplus energy for distributed generation on the utility grid. The modular design of the energy systems within the building is to serve as a scalable and repeatable model for a wide variety of building applications and climate zones. As a living laboratory of renewable energy, exploring and validating new applications of solar and other renewable technologies, the MARET Facility will house a wide variety of programs which will advance implementation of renewable energy throughout the region. These program goals include; Curriculum in renewable energy for pre-engineering transfer programs; Certification and degree programs for technical degrees for Energy Efficiency, Wind, Photovoltaic and Solar Thermal professionals; Short courses and workshops for building management and design professionals; Public education and demonstration projects in renewable energy through conferences and K-12 educational outreach; Technical degree offering in building construction incorporating “best practices” for energy efficiency and renewables; and Business incubators for new renewable energy businesses and new product development. The new MARET facility will support the mission of the US Department of Energy (DOE) Solar Program, “to improve America’s security, environmental quality, and economic prosperity through public-private partnerships that bring reliable and affordable solar energy technologies to the marketplace,” through a variety of educational and business assistance programs. Further, technical innovations planned for the MARET facility and its applied research activities will advance the Solar Program strategic goals to “reduce the cost of solar energy to the point it becomes competitive in relevant energy markets (e.g., buildings, power plants) and for solar technology to enable a sustainable solar industry.” Overarching Goals relative to program needs, future expansion, flexibility, quality of materials, and construction and operational costs:; Experimental: The structure and systems of the building operate as an educational resource. The systems are meant to be a source for data collection and study for building users and instructors; Educational: Part of the evolution of this building and its ongoing goals is to use the building as an educational tool, one where new ideas developed in the world and especially at Crowder can be tested further as part of MARET's curriculum; LEED Platinum: achieve highest level of LEED certification; Net Zero: The building will utilize existing wind and alternate energy sources on campus and add solar PVT panels and achieve as close as possible to a net zero energy usage; and Phase II: The phase II portion of this project will expand the Internet student area, additional classrooms, and labs, as well as an auditorium and exhibit area.

14 SOLAR ENERGY↗

DOE OSTI2015

Solar Assist for Administration Building and Community Gym/Pool (Final Report)

Tonto Apache Tribe applied to the Department of Energy’s “Tribal Energy Program” for the “Community Scale Clean Energy Projects” in Indian Country in 2013 to implement a solar project to reduce energy use in two tribal buildings. Total estimated project cost was $804,140, with the Department and Tribe each providing 50% of the project costs. Photovoltaic systems totaling 75 kW on the Administration Building and 192 kW on the Gymnasium were installed. We used roof tops and installed canopies in adjacent parking areas for mounting the systems. The installed systems were designed to offset 65% of the facilities electric load.

14 SOLAR ENERGY↗

DOE OSTI2015

Investigating the Effect of Pyridine Vapor Treatment on Perovskite Solar Cells (Abstract for a General Audience)

Solar power is an important and increasingly widespread form of renewable energy. If you’ve ever seen solar panels on someone’s roof, they are probably made with crystalline silicon. However, the possibility of creating cheaper and more efficient solar cells motivates scientists to continue searching for alternative materials. Perovskites are one of the newest and most promising solar cell materials: they have seen incredible efficiency gains in just a few years, jumping from 3.8% in 2009 to over 20% in 2014. Even though there’s been progress in improving perovskite-based device efficiency, there are many fundamental aspects of perovskite formation that are still not fully understood. The overall aim of my research is to study these processes and help fill in some of the knowledge gaps.

14 SOLAR ENERGY↗

DOE OSTI2012

Super Energy Efficient Design (S.E.E.D.) Home Evaluation

This report describes the results of evaluation by the Alliance for Residential Building Innovation (ARBI) Building America team of the “Super Energy Efficient Design” (S.E.E.D) home, a 1,935 sq. ft., single-story spec home located in Tucson, AZ. This prototype design was developed with the goal of providing an exceptionally energy efficient yet affordable home and includes numerous aggressive energy features intended to significantly reduce heating and cooling loads such as structural insulated panel (SIP) walls and roof, high performance windows, an ERV, an air-to-water heat pump with mixed-mode radiant and forced air delivery, solar water heating, and rooftop PV. Source energy savings are estimated at 45% over the Building America B10 Benchmark. System commissioning, short term testing, long term monitoring and detailed analysis of results was conducted to identify the performance attributes and cost effectiveness of the whole house measure package.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2013

External Insulation of Masonry Walls and Wood Framed Walls

The use of exterior insulation on a building is an accepted and effective means to increase the overall thermal resistance of the assembly that also has other advantages of improved water management and often increased air tightness of building assemblies. For thin layers of insulation (1” to 1 ½”), the cladding can typically be attached directly through the insulation back to the structure. For thicker insulation layers, furring strips have been added as a cladding attachment location. This approach has been used in the past on numerous Building America test homes and communities (both new and retrofit applications), and has been proven to be an effective and durable means to provide cladding attachment. However, the lack of engineering data has been a problem for many designers, contractors, and code officials. This research project developed baseline engineering analysis to support the installation of thick layers of exterior insulation on existing masonry and frame walls. Furthermore, water management details necessary to integrate windows, doors, decks, balconies and roofs were created to provide guidance on the integration of exterior insulation strategies with other enclosure elements.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2014

Moisture Risk in Unvented Attics Due to Air Leakage Paths

IBACOS completed an initial analysis of moisture damage potential in an unvented attic insulated with closed-cell spray polyurethane foam. To complete this analysis, the research team collected field data, used computational fluid dynamics to quantify the airflow rates through individual airflow (crack) paths, simulated hourly flow rates through the leakage paths with CONTAM software, correlated the CONTAM flow rates with indoor humidity ratios from Building Energy Optimization software, and used Wärme und Feuchte instationär Pro two-dimensional modeling to determine the moisture content of the building materials surrounding the cracks. Given the number of simplifying assumptions and numerical models associated with this analysis, the results indicate that localized damage due to high moisture content of the roof sheathing is possible under very low airflow rates. Reducing the number of assumptions and approximations through field studies and laboratory experiments would be valuable to understand the real-world moisture damage potential in unvented attics.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2014

Sunnyvale Marine Climate Deep Retrofit

The Alliance for Residential Building Innovation (ARBI) and Allen Gilliland of One Sky Homes collaborated on a marine climate retrofit project designed to meet both Passive House (PH) and Building America program standards. The scope included sealing, installing wall, roof and floor insulation (previously lacking), replacing windows, upgrading the heating and cooling system, and installing mechanical ventilation.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2015

Interaction of Unvented Attics With Living Space in Three Northeast Homes

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2013

Evaluation of Early Performance Results for Massachusetts Homes in the National Grid Pilot Deep Energy Retrofit Program

This research project evaluates post-retrofit performance measurements, energy use data and construction costs for 13 projects that participated in the National Grid Deep Energy Retrofit Pilot program. The projects implemented a package of measures defined by performance targets for building enclosure components and building enclosure air tightness. Nearly all of the homes reached a post-retrofit air tightness result of 1.5 ACH 50. Homes that used the chainsaw retrofit technique along with roof insulation, and wall insulation applied to the exterior had the best air tightness results and the lowest heating and cooling source energy use. Analysis of measure costs and project objectives yielded a categorization of costs relative to energy performance objectives. On average about ½ of the energy-related measure costs correspond primarily to energy-related objectives, and 20% of energy-related measure costs relate primarily to non-energy objectives.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗