02807nas a2200253 4500008004100000022001300041245012200054210006900176260001200245300001100257490000800268520202500276653001602301653001902317653002402336653000802360653001202368100001402380700001802394700002102412700002502433700002802458856006702486 2019 eng d a0360132300aSplit-pane electrochromic window control based on an embedded photometric device with real-time daylighting computing0 aSplitpane electrochromic window control based on an embedded pho c08/2019 a1062290 v1613 a

Well-designed electrochromic (EC) glazing control can improve the energy performance of buildings and visual comfort of occupants in highly glazed buildings. This paper designed and demonstrated a compact integrated EC glazing automation system to control tint states of a split-pane EC window according to variations of sky conditions. The control is based on monitoring the luminance distribution of the sky and real-time lighting computation for a building interior, using an embedded photometric device (EPD). It optimizes tint states of EC glazing to offer sufficient daylight provision and temper discomfort glare for occupants, which potentially mitigates excessive solar heat gain. ’In-situ’ experiments were conducted in a full-scale testbed to demonstrate the daylighting performance under various sky conditions. Experimental results showed 83% of the working time for work-plane illuminance (WPI) and 95% of the time for daylight glare probability (DGP) were constrained in comfort range (WPI[500, 2000] lux, DGP  0.35) by the automated EC glazing (controlled by EPD) under clear skies; 68% of the time for WPI and 94% of the time for DGP in confined range under clear skies with thin clouds; 62% of the time for WPI and 85% of the time for DGP in confined range under partly cloudy skies.

10adaylighting10aelectrochromic10aEmbedded Controller10aHDR10awindows1 aWu, Yujie1 aWang, Taoning1 aLee, Eleanor, S.1 aKämpf, Jérôme, H.1 aScartezzini, Jean-Louis uhttps://linkinghub.elsevier.com/retrieve/pii/S036013231930439100763nas a2200205 4500008003900000245011500039210006900154260003100223653002400254653003300278653002400311653002100335653002500356653001300381100002100394700001900415700002100434700002300455856007900478 2015 d00aDiscomfort glare with complex fenestration systems and the impact on energy use when using daylighting control0 aDiscomfort glare with complex fenestration systems and the impac aBern, Switzerlandc11/201510abuilding simulation10aComplex fenestration systems10adaylighting control10aDiscomfort Glare10aEnergy Use Intensity10aradiance1 aHoffmann, Sabine1 aMcNeil, Andrew1 aLee, Eleanor, S.1 aKalyanam, Raghuram uhttps://facades.lbl.gov/publications/discomfort-glare-complex-fenestration03133nas a2200205 4500008003900000245010300039210006900142260001200211300001200223490000700235520243300242653001602675653002302691653004002714653002602754653003202780100002002812700002102832856007402853 2015 d00aMeasured daylighting potential of a static optical louver system under real sun and sky conditions0 aMeasured daylighting potential of a static optical louver system c10/2015 a347-3590 v923 a

By utilizing highly specular surfaces and engineered profile geometry, optical sunlight redirecting systems integrated into the overhead “clerestory” zone of the building facade present the potential to enlarge the daylighting zone by redirecting the luminous flux incident on the window deeper into the space than conventional shading systems. In addition, by developing system geometry to redirect daylight to specific zones within the space, optical light redirecting systems have the potential to avoid the glare conditions commonly produced by conventional facade shading systems that direct significant amounts of daylight below head height into the occupant's field of view. In this case study, side-by-side comparisons were made over solstice-to-solstice changes in sun and sky conditions between an optical louver system (OLS) and a conventional Venetian blind set at a horizontal slat angle and located inboard of a south-facing, small-area, clerestory window in a full-scale office testbed. Daylight autonomy (DA), window luminance, and ceiling luminance uniformity were used to assess performance. The performance of both systems was found to have significant seasonal variation, where performance under clear sky conditions improved as maximum solar altitude angles transitioned from solstice to equinox. Although the OLS produced fewer hours per day of DA on average than the Venetian blind, the OLS never exceeded the designated 2000 cd/m2 threshold for window glare. In contrast, the Venetian blind was found to exceed the visual discomfort threshold over a large fraction of the day during equinox conditions (from 40 to 64% of the test day between August 22 and October 12). Notably, these peak periods of visual discomfort occurred during the best periods of daylighting performance. Luminance uniformity was analyzed using calibrated high dynamic range luminance images. Under clear sky conditions, the OLS was found to increase the luminance of the ceiling as well as produce a more uniform distribution of luminance over the ceiling. Compared to conventional venetian blinds, the static optical sunlight redirecting system studied has the potential to significantly reduce the annual electrical lighting energy demand of a daylit space and improve the quality from the perspective of building occupants by consistently transmitting useful daylight while eliminating window glare.

10adaylighting10afield measurements10ahigh dynamic range luminance images10aoptical louver system10asunlight redirecting system1 aKonis, Kyle, S.1 aLee, Eleanor, S. uhttps://facades.lbl.gov/publications/measured-daylighting-potential-007924nas a2200265 4500008003900000245004800039210004800087260006500135520707300200653002507273653001607298653003807314653002107352653001507373653002207388653002507410653002107435653002007456653001907476100001907495700002207514700002107536700002707557856007407584 2014 d00aHigh Performance Building Mockup in FLEXLAB0 aHigh Performance Building Mockup in FLEXLAB aBerkeley, CAbLawrence Berkeley National Laboratoryc12/20143 a

Genentech has ambitious energy and indoor environmental quality performance goals for Building 35 (B35) being constructed by Webcor at the South San Francisco campus. Genentech and Webcor contracted with the Lawrence Berkeley National Laboratory (LBNL) to test building systems including lighting, lighting controls, shade fabric, and automated shading controls in LBNL's new FLEXLAB facility. The goal of the testing is to ensure that the systems installed in the new office building will function in a way that reduces energy consumption and provides a comfortable work environment for employees.

LBNL tested three facades of the new office building in the rotating FLEXLAB testbed: west, south and east. External shading, lighting, and internal shading control was configured for each orientation to replicate the conditions of B35. The three facades were each tested for one week three times between July and October 2014. Changes were made between each test to improve the performance of the systems.

Linear pendant LED light fixtures will illuminate the open office areas of the office building. These fixtures were installed in FLEXLAB. The wide spacing between rows of light fixtures results in a low lighting power density of 0.57 W/ft2 in the open office areas, while still meeting the average illuminance criteria of 300 lux (28 footcandles). A combination of the wide spacing and optics of the light fixture creates a nonuniform lighting pattern on the ceiling of the space. Changing to a diffuse lens on the uplight will help reduce abrupt changes in luminance on the ceiling but non-uniformity will persist due to the wide spacing.

The pendant light fixtures allow separate control of the downward and upward light. The lighting control design aims to enhance the quality of space by dimming upward light unison providing uniform patterns of electric light on the ceiling. The downward light of each fixture dims to provide just enough light to meet illuminance criteria below the fixture.

Webcor installed two lighting control systems manufactured by Enlighted and Encelium for testing in FLEXLAB. The Encelium system uses an open loop control architecture with a ceiling-mounted photosensor at each facade (inside of the automated shade). While there is greater variation in workplane illuminance provided by the Encelium system, the system is better able to control upward versus downward lighting and is able to control the lighting according to the lighting design intent. The architecture of the Encelium system offers more functional flexibility by allowing any input (sensors, switches etc.) or multiple inputs to affect any fixture.

The Enlighted control system uses closed loop architecture with two photosensors per fixture (one for upward light and one for downward light). The Enlighted system controlled the lights more precisely than the Encelium system to meet workplane illuminance requirements, however the upward versus downward light control did not behave according to the lighting design intent.

MechoSystems provided motorized window shades and automated control. The shades in each window had a different color fabric, one dark grey and one medium grey. Both shade fabrics were an open weave with 3% openness. Genentech selected the dark colored shade because it provides a better view of the exterior compared to the lighter colored shade. Anecdotal evidence suggests that some occupants may experience direct glare with 3% open fabric while other occupants will not experience glare under the same conditions. Visual discomfort during the worst case sunny winter condition was not evaluated. However, the east-facing orientation during the equinox period was exposed to low sun angles in the third test period so findings of just acceptable visual discomfort are expected to be similar to what might be experienced during the winter.

The shades operated as expected on sunny days (which was the predominant condition during the test period). The testing identified substantial potential energy savings for the lighting systems by stopping the shade above the sill, preventing the shade from completely covering the window and allowing the sun to shine deeper into the space through the bottom few inches of the window. On partly cloudy days, which occurred more frequently after our testing concluded, anecdotal evidence suggests that the shades could be raised more often. LBNL suggests that a second threshold be implemented which drops the shade partway to prevent direct glare from bright sun, but doesn't close the shade down to the height required to limit sunshine depth.

Thermal comfort analysis suggests that occupants seated near the shaded window will be comfortable around 80% of the time. The 20% of time where the observed conditions fall outside the ASHRAE Standard 55 are almost always due to occupants being cold in the morning. This discomfort is mostly driven by cold surrounding surfaces causing a low mean radiant temperature and overcooling from outside air during economizer mode. Only one thermal comfort station, located near the facade, was used for the experiment. Thermal comfort further from the facade is unknown but is likely to be better due to the increased distance from the relatively cold facade.

Visual comfort studies indicated that occupants could sit as close as 3.5 feet to the east and west facade and 2.5 feet to the south facade when facing parallel to the window. Occupants must sit further away from the window to be comfortable when facing the window directly. Occupants should be 3.5 feet away when facing the south facade, 4.5 feet away when facing the west facade and 5.5 feet away when facing the east facade. Thermal comfort studies show that sitting within 30 inches of the facade has a negligible effect on comfort ratings.

Daylighting controls reduced lighting energy use in FLEXLAB by 46% for east facade, 34% for south facade and 35% for west facade over 30 feet deep perimeter zone between 7 AM and 7 PM local time at autumn equinox. Occupancy controls will further reduce lighting energy use, though they were not implemented for the test due to the cell being tested unoccupied.

Genentech, Webcor, and the architectural and engineering team had access to the FLEXLAB during and for a month following the test period to observe, work, and discuss operational issues with employees and staff. The project team made their own qualitative observations about the space in terms of view, adequacy of lighting and daylight levels, color, furniture placement, etc. The project team worked collaboratively with the LBNL team to fine tune details of component design, control settings, troubleshooting, and operations. Because Genentech is introducing a new model for their work environment, a non-assigned workplace, there were detailed discussions on how to educate the occupants about the new technologies and their operational modes. Commissioning and tuning procedures were also discussed.

10acommercial buildings10adaylighting10aenergy management control systems10aexterior shading10afield test10alighting controls10amonitored evaluation10ashading controls10athermal comfort10avisual comfort1 aMcNeil, Andrew1 aKohler, Christian1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/high-performance-building-mockup00869nas a2200109 4500008003900000245004400039210004400083260001200127520052400139100002200663856007400685 2013 d00aComplex Fenestration Calculation Module0 aComplex Fenestration Calculation Module c10/20133 a

This document is organized to give you the best possible look into the EnergyPlus calculations. First, the concepts of modeling in EnergyPlus are presented. These include descriptions of the zone heat balance process, air loop/plant loop processes as well as other important processes for the building simulation.

Discussions during the modeling process may reference specific "object names" as found in the Input/Output Reference document.

The remainder of the document focuses on individual models.

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/complex-fenestration-calculation01830nas a2200241 4500008003900000022001300039245013000052210006900182260001100251300001400262490000800276520103900284653002701323653003701350653002201387653001801409100002201427700002001449700001701469700001401486700001901500856006901519 2013 d a0927024800aModeling of optical and energy performance of tungsten-oxide-based electrochromic windows including their intermediate states0 aModeling of optical and energy performance of tungstenoxidebased c1/2013 a129 - 1350 v1083 a

Tungsten-oxide-based electrochromic (EC) windows are currently the most robust and matured dynamic windows where the transmittance of visual light and near-infrared radiation can be controlled by a small applied voltage. In its standard application, the window is commonly either in its clear or colored state. In this contribution, we study the optical and energy performance of such window in the fully bleached and fully colored state as well as when it is kept in intermediate states. Different configurations in terms of placement of the EC layer stack and possible additional low-emissivity (low-E) coating within the insulated glass unit are considered. Using optical data and software tools we find that even a small coloration has a significant effect on the energy performance because the solar heat gain coefficient is readily reduced by the absorption of the EC layer stack. We compare the performance of the EC windows to commercially available solar-control (spectrally selective) low-E windows.

10aElectrochromic windows10aEnergy efficient window modeling10aEnergy simulation10aSmart windows1 aLim, Sunnie, H.N.1 aIsidorsson, Jan1 aSun, Lizhong1 aKwak, Leo1 aAnders, André uhttps://facades.lbl.gov/publications/modeling-optical-and-energy01318nas a2200193 4500008003900000245006300039210006300102260002500165520071500190100002400905700001500929700001900944700002200963700002900985700002601014700002001040700001801060856004601078 2012 d00aApplication of a stochastic window use model in EnergyPlus0 aApplication of a stochastic window use model in EnergyPlus aMadison, WIc08/20123 a

Natural ventilation, used appropriately, has the potential to provide both significant HVAC energy savings, and improvements in occupant satisfaction.

Central to the development of natural ventilation models is the need to accurately represent the behavior of building occupants. The work covered in this paper describes a method of implementing a stochastic window model in EnergyPlus. Simulated window use data from three stochastic window opening models was then compared to measured window opening behavior, collected in a naturally-ventilated office in California. Recommendations regarding the selection of stochastic window use models, and their implementation in EnergyPlus, are presented.

1 aDutton, Spencer, M.1 aZhang, Hui1 aZhai, Yongchao1 aArens, Edward, A.1 aSmires, Youness, Bennani1 aBrunswick, Samuel, L.1 aKonis, Kyle, S.1 aHaves, Philip uhttps://escholarship.org/uc/item/2gm7r78302907nas a2200157 4500008003900000245014300039210006900182260002200251520231100273653001602584653002702600653003502627653002102662100002002683856004602703 2012 d00aEffective Daylighting: Evaluating Daylighting Performance in the San Francisco Federal Building from the Perspective of Building Occupants0 aEffective Daylighting Evaluating Daylighting Performance in the  aBerkeleyc01/20123 a

Commercial office buildings promoted as “sustainable,” “energy efficient,” “green,” or “high performance” often reference use of daylight as a key strategy for reducing energy consumption and enhancing indoor environmental quality. However, buildings are rarely studied in use to examine if the design intent of a sufficiently daylit and a visually comfortable work environment is achieved from the perspective of building occupants or how occupant use of shading devices may affect electrical lighting energy reduction from photocontrols. This dissertation develops a field-based approach to daylighting performance assessment that pairs repeated measures of occupant subjective response using a novel desktop polling station device with measurements of the physical environment acquired using High Dynamic Range (HDR) imaging and other environmental sensors with the objective of understanding the physical environmental conditions acceptable to occupants. The approach is demonstrated with a 6-month field study involving (N=44) occupants located in perimeter and core open-plan office spaces in the San Francisco Federal Building1 (SFFB). Over 23,100 subjective assessments paired with physical measures were analyzed to develop models of visual discomfort and shade control and to examine the assumptions of existing daylighting performance indicators. The analysis found that existing daylight performance indicators overestimated the levels of daylight illuminance required by occupants to work comfortably without overhead ambient electrical lighting. Time-lapse observation of interior roller shades showed that existing shade control models overestimated the frequency of shade operation and underestimated the level of facade occlusion due to interior shades. Comparison of measured results to the daylighting objectives of the SFFB showed that available daylight enabled electrical lighting energy reduction in the perimeter zones but not in the open-plan core zones. The results extend existing knowledge regarding the amount of daylight illuminance acceptable for occupants to work comfortably without overhead electrical lighting and for the physical variables (and stimulus intensities) associated with visual discomfort and the operation of interior shading devices.

10adaylighting10aperformance assessment10aSan Francisco Federal Building10ashading controls1 aKonis, Kyle, S. uhttps://escholarship.org/uc/item/7q35m7nq01680nas a2200157 4500008003900000245011100039210006900150260001200219520106500231653005301296653004101349100002201390700001601412700002101428856007301449 2012 d00aA Practical Framework for Sharing and Rendering Real-World Bidirectional Scattering Distribution Functions0 aPractical Framework for Sharing and Rendering RealWorld Bidirect c10/20123 a

The utilization of real-world materials has been hindered by a lack of standards for sharing and interpreting measured data. This paper presents an XML representation and an Open Source C library to support bidirectional scattering distribution functions (BSDFs) in data-driven lighting simulation and rendering applications.The library provides for the efficient representation, query, and Monte Carlo sampling of arbitrary BSDFs in amodel-free framework. Currently, we support two BSDF data representations: one using a fixed subdivision of thehemisphere, and one with adaptive density. The fixed type has advantages for certain matrix operations, while theadaptive type can more accurately represent highly peaked data. We discuss advanced methods for data-driven BSDF rendering for both types, including the proxy of detailed geometry to enhance appearance and accuracy. We also present an advanced interpolation method to reduce measured data into these standard representations. We end with our plan for future extensions and sharing of BSDF data.

10abuilding technology and urban systems department10awindows and envelope materials group1 aWard, Gregory, J.1 aKurt, Murat1 aBonneel, Nicolas uhttps://facades.lbl.gov/publications/practical-framework-sharing-and00572nas a2200145 4500008003900000245011600039210006900155260001200224100003100236700001900267700002200286700002200308700002100330856007500351 2011 d00aModeling solar heat gains of complex fenestration systems using bidirectional scattering distribution functions0 aModeling solar heat gains of complex fenestration systems using  c09/20111 aNouidui, Thierry, Stephane1 aMcNeil, Andrew1 aKohler, Christian1 aCoffey, Brian, E.1 aLee, Eleanor, S. uhttps://facades.lbl.gov/publications/modeling-solar-heat-gains-complex01474nas a2200157 4500008004100000050001500041245014400056210006900200260001100269490000600280520089100286100002001177700002101197700002201218856007601240 2011 eng d aLBNL-4417E00aVisual Comfort Analysis of Innovative Interior and Exterior Shading Systems for Commercial Buildings using High Resolution Luminance Images0 aVisual Comfort Analysis of Innovative Interior and Exterior Shad c1/20110 v73 a

The objective of this study was to explore how calibrated high dynamic range (HDR) images (luminance maps) acquired in real world daylit environments can be used to characterize, evaluate, and compare visual comfort conditions of innovative facade shading and light-redirecting systems. Detailed (1536 x 1536 pixel) luminance maps were time-lapse acquired from two view positions in an unoccupied full scale testbed facility. These maps were analyzed using existing visual comfort metrics to quantify how innovative interior and exterior shading systems compare to conventional systems under real sun and sky conditions over a solstice-to-solstice test interval. The results provide a case study in the challenges and potential of methods of visualizing, evaluating and summarizing daily and seasonal variation of visual comfort conditions computed from large sets of image data.

1 aKonis, Kyle, S.1 aLee, Eleanor, S.1 aClear, Robert, D. uhttps://facades.lbl.gov/publications/visual-comfort-analysis-innovative02589nas a2200289 4500008004100000245010600041210006900147260003400216520165800250653001701908653001701925653001701942653002701959653001201986653002801998653002602026653001202052653001802064100002102082700001602103700002502119700001802144700002202162700002102184700002602205856006802231 2010 eng d00aExperimental and Numerical Examination of the Thermal Transmittance of High Performance Window Frames0 aExperimental and Numerical Examination of the Thermal Transmitta aClearwater Beach, FLc09/20103 a

While window frames typically represent 20-30% of the overall window area, their impact on the total window heat transfer rates may be much larger. This effect is even greater in low-conductance (highly insulating) windows which incorporate very low conductance glazings. Developing low-conductance window frames requires accurate simulation tools for product research and development.

The Passivhaus Institute in Germany states that windows (glazing and frames, combined) should have U-values not exceeding 0.80 W/(m2 K). This has created a niche market for highly insulating frames, with frame U-values typically around 0.7-1.0 W/(m2 K). The U-values reported are often based on numerical simulations according to international simulation standards. It is prudent to check the accuracy of these calculation standards, especially for high performance products before more manufacturers begin to use them to improve other product offerings.

In this paper the thermal transmittance of five highly insulating window frames (three wooden frames, one aluminum frame and one PVC frame), found from numerical simulations and experiments, are compared. Hot box calorimeter results are compared with numerical simulations according to ISO 10077-2 and ISO 15099. In addition CFD simulations have been carried out, in order to use the most accurate tool available to investigate the convection and radiation effects inside the frame cavities.

Our results show that available tools commonly used to evaluate window performance, based on ISO standards, give good overall agreement, but specific areas need improvement.

10aexperimental10aFenestration10aframe cavity10aheat transfer modeling10ahot box10ainternational standards10athermal transmittance10aU-value10awindow frames1 aGustavsen, Arlid1 aTalev, Goce1 aArasteh, Dariush, K.1 aGoudey, Howdy1 aKohler, Christian1 aUvsløkk, Sivert1 aJelle, Bjørn, Petter uhttps://facades.lbl.gov/publications/experimental-and-numerical02555nas a2200205 4500008003900000245009100039210006900130260001200199300001200211490000800223520188300231100002102114700002902135700002202164700002202186700002002208700002102228700002202249856007802271 2009 d00aField Measurements of Innovative Indoor Shading Systems in a Full-Scale Office Testbed0 aField Measurements of Innovative Indoor Shading Systems in a Ful c10/2009 a706-7280 v1153 a

The development of spectrally selective low-e glass with its superior solar control and high daylight admission has led to widespread use of large-area, "transparent" or visually clear glass windows in commercial building facades. This type of façade can provide significant inherent daylighting potential (ability to offset lighting energy use) and move us closer to the goal of achieving zero energy buildings, if not for the unmitigated glare that results from the unshaded glazing. Conventional shading systems result in a significant loss of daylight and view. Can innovative shading solutions successfully balance the tradeoffs between daylight, solar heat gains, discomfort glare, and view?

To investigate this issue, a six-month solstice-to-solstice field study was conducted in a sunny climate to measure the thermal and daylighting performance of a south-facing, full- scale, office testbed with large-area windows and a variety of innovative indoor shading systems. Indoor shading systems included manually-operated and automated roller shades, Venetian blinds, daylight-redirecting blinds, and a static translucent diffusing panel placed inboard of the window glazing. These innovative systems were compared to a reference shade lowered to block direct sun.

With continuous dimming controls, all shading systems yielded lighting energy savings between 43-69% compared to a non-dimming case, but only the automated systems were able to meet visual comfort criteria throughout the entire monitored period. Cooling loads due to solar and thermal loads from the window were increased by 2-10% while peak cooling loads were decreased by up to 14%. The results from this experiment illustrate that some indoor shading systems can preserve daylight potential while meeting comfort requirements. Trends will differ significantly depending on application.

1 aLee, Eleanor, S.1 aDiBartolomeo, Dennis, L.1 aKlems, Joseph, H.1 aClear, Robert, D.1 aKonis, Kyle, S.1 aYazdanian, Mehry1 aPark, Byoung-Chul uhttps://facades.lbl.gov/publications/field-measurements-innovative-indoor05111nas a2200217 4500008004100000245007400041210006900115260001200184520439000196100002104586700002704607700002904634700002204663700002204685700002004707700002604727700002104753700002004774700002504794856007404819 2009 eng d00aHigh Performance Building Facade Solutions: PIER Final Project Report0 aHigh Performance Building Facade Solutions PIER Final Project Re c12/20093 a

Building façades directly influence heating and cooling loads and indirectly influence lighting loads when daylighting is considered, and are therefore a major determinant of annual energy use and peak electric demand. façades also significantly influence occupant comfort and satisfaction, making the design optimization challenge more complex than many other building systems.

This work focused on addressing significant near-term opportunities to reduce energy use in California commercial building stock by a) targeting voluntary, design-based opportunities derived from the use of better design guidelines and tools, and b) developing and de ploying more efficient glazings, shading systems, daylighting systems, façade systems and integrated controls.

This two-year project, supported by the California Energy Commission PIER program and the US Department of Energy, initiated a collaborative effort between The Lawrence Berkeley National Laboratory (LBNL) and major stakeholders in the façades industry to develop, evaluate, and accelerate market deployment of emerging, high-performance, integrated façade solutions. The LBNL Windows Testbed Facility acted as the primary cata lyst and mediator on both sides of the building industry supply-user business transaction by a) aiding component suppliers to create and optimize cost effective, integrated systems that work, and b) demonstrating and verifying to the owner, designer, and specifier community that these integrated systems reliably deliver required energy performance. An industry consortium was initiated amongst approximately seventy disparate stakeholders, who unlike the HVAC or lighting industry, has no single representative, multi-disciplinary body or organized means of communicating and collaborating. The consortium provided guidance on the project and more importantly, began to mutually work out and agree on the goals, criteria, and pathways needed to attain the ambitious net zero energy goals defined by California and the US.

A collaborative test, monitoring, and reporting protocol was also formulated via the Windows Testbed Facility in collaboration with industry partners, transitioning industry to focus on the import ance of expecting measured performance to consistently achieve design performance expectations. The facility enables accurate quantification of energy use, peak demand, and occupant comfort impacts of synergistic façade-lighting-HVAC systems on an apples-to-apples comparative basis and its data can be used to verify results from simulations.

Emerging interior and exterior shading technologies were investigated as potential near-term, low-cost solutions with potential broad applicability in both new and retrofit construction. Commercially-available and prototype technologies were developed, tested, and evaluated. Full-scale, monitored field tests were conducted over solstice-to-solstice periods to thoroughly evaluate the technologies, uncover potential risks associated with an unknown, and quantify performance benefits. Exterior shading systems were found to yield net zero energy levels of performance in a sunny climate and significant reductions in summer peak demand. Automated interior shading systems were found to yield significant daylighting and comfort-related benefits.

In support of an integrated design process, a PC-based commercial fenestration (COMFEN) software package, based on EnergyPlus, was developed that enables architects and engineers to x quickly assess and compare the performance of innovative façade technologies in the early sketch or schematic design phase. This tool is publicly available for free and will continue to improve in terms of features and accuracy. Other work was conducted to develop simulation tools to model the performance of any arbitrary complex fenestration system such as common Venetian blinds, fabric roller shades as well as more exotic innovative façade systems such as optical louver systems.

The principle mode of technology transfer was to address the key market barriers associated with lack of information and facile simulation tools for early decisionmaking. The third party data generated by the field tests and simulation data provided by the COMFEN tool enables utilities to now move forward toward incentivizing these technologies in the marketplace.

1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E.1 aDiBartolomeo, Dennis, L.1 aKlems, Joseph, H.1 aClear, Robert, D.1 aKonis, Kyle, S.1 aHitchcock, Robert, J.1 aYazdanian, Mehry1 aMitchell, Robin1 aKonstantoglou, Maria uhttps://facades.lbl.gov/publications/high-performance-building-facade02357nas a2200193 4500008003900000245006700039210006600106260006100172520166400233100002101897700002701918700002901945700002201974700002201996700002002018700002502038700002202063856007802085 2009 d00aInnovative Façade Systems for Low-energy Commercial Buildings0 aInnovative Façade Systems for Lowenergy Commercial Buildings aBerkeleybLawrence Berkeley National Laboratoryc11/20093 a

Glazing and façade systems have very large impacts on all aspects of commercial building performance. They directly influence peak heating and cooling loads, and indirectly influence lighting loads when daylighting is considered. In addition to being a major determinant of annual energy use, they can have significant impacts on peak cooling system sizing, electric load shape, and peak electric demand. Because they are prominent architectural and design elements and because they influence occupant preference, satisfaction and comfort, the design optimization challenge is more complex than with many other building systems.

Façade designs that deliberately recognize the fundamental synergistic relationships between the façade, lighting, and mechanical systems have the potential to deliver high performance over the life of the building. These "integrated" façade systems represent a key opportunity for commercial buildings to significantly reduce energy and demand, helping to move us toward our goal of net zero energy buildings by 2030.

Provision of information — technology concepts, measured data, case study information, simulation tools, etc. — can enable architects and engineers to define integrated façade solutions and draw from a wide variety of innovative technologies to achieve ambitious energy efficiency goals.

This research is directed toward providing such information and is the result of an on‐going collaborative research and development (R&D) program, supported by the U.S. Department of Energy and the California Energy Commission Public Interest Energy Research (PIER) program.

1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E.1 aDiBartolomeo, Dennis, L.1 aKlems, Joseph, H.1 aClear, Robert, D.1 aKonis, Kyle, S.1 aKonstantoglou, Maria1 aPerepelitza, Mark uhttps://facades.lbl.gov/publications/innovative-fa-ade-systems-low-energy01654nas a2200145 4500008004100000050001500041245006800056210006800124260001200192520115600204100002501360700002201385700002401407856007701431 2009 eng d aLBNL-2804E00aModeling Windows in Energy Plus with Simple Performance Indices0 aModeling Windows in Energy Plus with Simple Performance Indices c10/20093 a

The paper describes the development of a model specification for performance monitoring systems for commercial buildings. The specification focuses on four key aspects of performance monitoring:

The aim is to assist building owners in specifying the extensions to their control systems that are required to provide building operators with the information needed to operate their buildings more efficiently and to provide automated diagnostic tools with the information required to detect and diagnose faults and problems that degrade energy performance.

The paper reviews the potential benefits of performance monitoring, describes the specification guide and discusses briefly the ways in which it could be implemented. A prototype advanced visualization tool is also described, along with its application to performance monitoring. The paper concludes with a description of the ways in which the specification and the visualization tool are being disseminated and deployed.

1 aArasteh, Dariush, K.1 aKohler, Christian1 aGriffith, Brent, T. uhttps://facades.lbl.gov/publications/modeling-windows-energy-plus-simple01238nas a2200133 4500008004100000245005400041210005400095260003300149520077800182100002500960700002300985700002101008856007501029 2009 eng d00aSimulating Complex Window Systems Using BSDF Data0 aSimulating Complex Window Systems Using BSDF Data aQuebec City, Canadac06/20093 a

Nowadays, virtual models are commonly used to evaluate the performance of conventional window systems. Complex fenestration systems can be difficult to simulate accurately not only because of their geometry but also because of their optical properties that scatter light in an unpredictable manner. Bi-directional Scattering Distribution Functions (BSDF) have recently been developed based on a mixture of measurements and modelling to characterize the optics of such systems. This paper describes the workflow needed to create then use these BSDF datasets in the Radiance lighting simulation software. Limited comparisons are made between visualizations produced using the standard ray-tracing method, the BSDF method, and that taken in a full-scale outdoor mockup.

1 aKonstantoglou, Maria1 aJonsson, Jacob, C.1 aLee, Eleanor, S. uhttps://facades.lbl.gov/publications/simulating-complex-window-systems02372nas a2200181 4500008004100000050001500041245012000056210006900176300001200245490000700257520173300264100002101997700002502018700002602043700002402069700002202093856007502115 2008 eng d aLBNL-1022E00aDeveloping Low-Conductance Window Frames: Capabilities and Limitations of Current Window Heat Transfer Design Tools0 aDeveloping LowConductance Window Frames Capabilities and Limitat a131-1530 v323 a

While window frames typically represent 20-30% of the overall window area, their impact on the total window heat transfer rates may be much larger. This effect is even greater in low-conductance (highly insulating) windows which incorporate very low conductance glazings. Developing low-conductance window frames requires accurate simulation tools for product research and development. Based on a literature review and an evaluation of current methods of modeling heat transfer through window frames, we conclude that current procedures specified in ISO standards are not sufficiently adequate for accurately evaluating heat transfer through the low-conductance frames.

We conclude that the near-term priorities for improving the modeling of heat transfer through low-conductance frames are:

  1. Add 2-D view-factor radiation to standard modeling and examine the current practice of averaging surface emissivity based on area weighting and the process of making an equivalent rectangular frame cavity.
  2. Assess 3-D radiation effects in frame cavities and develop recommendation for inclusion into the design fenestration tools.
  3. Assess existing correlations for convection in vertical cavities using CFD.
  4. Study 2-D and 3-D natural convection heat transfer in frame cavities for cavities that are proven to be deficient from item 3 above. Recommend improved correlations or full CFD modeling into ISO standards and design fenestration tools, if appropriate.
  5. Study 3 D hardware short-circuits and propose methods to ensure that these effects are incorporated into ratings.
  6. Study the heat transfer effects of ventilated frame cavities and propose updated correlations.
1 aGustavsen, Arlid1 aArasteh, Dariush, K.1 aJelle, Bjørn, Petter1 aCurcija, Dragan, C.1 aKohler, Christian uhttps://facades.lbl.gov/publications/developing-low-conductance-window01181nas a2200133 4500008004100000245008100041210006900122260003200191520068400223100002500907700001800932700002200950856007500972 2008 eng d00aHighly Insulating Glazing Systems using Non-Structural Center Glazing Layers0 aHighly Insulating Glazing Systems using NonStructural Center Gla aSalt Lake City, UTc06/20083 a

Three layer insulating glass units with two low-e coatings and an effective gas fill are known to be highly insulating, with center-of-glass U-factors as low as 0.57 W/m2-K (0.10 Btu/h-ft2-°F). Such units have historically been built with center layers of glass or plastic which extend all the way through the spacer system.

This paper shows that triple glazing systems with non-structural center layers which do not create a hermetic seal at the edge have the potential to be as thermally efficient as standard designs, while potentially removing some of the production and product integration issues that have discouraged the use of triples.

1 aArasteh, Dariush, K.1 aGoudey, Howdy1 aKohler, Christian uhttps://facades.lbl.gov/publications/highly-insulating-glazing-systems01696nas a2200193 4500008004100000245018300041210006900224260001200293300001100305490000700316520097400323100002301297700002601320700002201346700001901368700002101387700001801408856007601426 2008 eng d00aThe structure and electron energy loss near edge structure of tungsten oxide thin films prepared by pulsed cathodic arc deposition and plasma-assisted pulsed magnetron sputtering0 astructure and electron energy loss near edge structure of tungst c04/2008 a1752160 v203 a

The microstructure and energy-loss near-edge structure (ELNES) of pulsed cathodic arc and pulsed magnetron sputtered WO3 thin films were investigated. It was found that the cathodic arc deposited material consisted of the α-WO3 phase with a high degree of crystallinity. In contrast, the magnetron sputtered material was highly disordered making it difficult to determine its phase. A self-consistent real space multiple scattering approach was used to calculate the NES of the various phases of WO3. Each phase was found to exhibit a unique NES allowing different phases of WO3 to be identified. The real space approach also allowed the origin of the main features in the NES to be investigated as the cluster size increased. The calculated NES for the room temperature γ-WO3 was found to compare well to previous X-ray absorption spectra and to NES obtained by full-potential band structure calculation.

1 aField, Matthew, R.1 aMcCulloch, Dougal, G.1 aLim, Sunnie, H.N.1 aAnders, André1 aKeast, Vicki, J.1 aBurgess, R.W. uhttps://facades.lbl.gov/publications/structure-and-electron-energy-loss02585nas a2200205 4500008004100000245005400041210005100095260006100146300001000207520191200217100002002129700002202149700002202171700002302193700002502216700002202241700001602263700002402279856007602303 2008 eng d00aWINDOW 6.2/THERM 6.2 Research Version User Manual0 aWINDOW 62THERM 62 Research Version User Manual aBerkeleybLawrence Berkeley National Laboratoryc01/2008 a1-1263 a

WINDOW 6 and THERM 6 Research Versions are software programs developed at Lawrence Berkeley National Laboratory (LBNL) for use by manufacturers, engineers, educators, students, architects, and others to determine the thermal and solar optical properties of glazing and window systems.

WINDOW 6 and THERM 6 are significant updates to LBNL's WINDOW 5 and THERM 5 computer program because of the added capability to model complex glazing systems, such as windows with shading systems, in particular venetian blinds. Besides a specific model for venetian blinds and diffusing layers, WINDOW 6 also includes the generic ability to model any complex layer if the Transmittance and Reflectance are known as a function of incoming and outgoing angles.

The algorithms used in these versions of the programs to determine the properties of windows with shading layers are relatively new and should be considered as informative but not definitive.

As such, for windows with shading layers, the results are intended for research purposes only. Pending further validation efforts, results for windows with sh ading layers should not be used for NFRC certified calculations of design decisions in real buildings.

All calculations for products without shading layers are identical to those from WINDOW 5.2.

WINDOW 6 Research Version includes all of the WINDOW 5 capabilities with the addition of shading algorithms from ISO15099 which are incorporated into the program, as well as an extension of those algorithms with the matrix calculation method.

THERM 6 Research Version includes all of the THERM 5 capabilities with the addition of being able to import and model WINDOW 6 glazing systems with shading devices. Those THERM 6 files with shading devices can them be imported into the WINDOW 6 Frame Library and whole windows with shading devices can then be modeled in WINDOW 6.

1 aMitchell, Robin1 aKohler, Christian1 aKlems, Joseph, H.1 aRubin, Michael, D.1 aArasteh, Dariush, K.1 aHuizenga, Charlie1 aYu, Tiefeng1 aCurcija, Dragan, C. uhttps://facades.lbl.gov/publications/window-62therm-62-research-version04075nas a2200265 4500008003900000245014000039210006900179260002200248520314300270653003503413653002803448653001603476653002003492653002203512653001903534100002103553700002203574700002203596700002403618700002003642700002203662700002803684700002703712856007003739 2007 d00aDaylighting the New York Times Headquarters Building: Final Report: Commissioning Daylighting Systems and Estimation of Demand Response0 aDaylighting the New York Times Headquarters Building Final Repor aBerkeleyc08/20073 a

The technical energy-savings potential for smart integrated window-daylighting systems is excellent and can yield significant reductions in US commercial building energy use if adopted by a significant percentage of the market. However, conventional automated shades and daylighting controls have been commercially available for over two decades with less than 1-2% market penetration in the US. As with many innovations, the problem with accelerating market adoption is one of demonstrating real performance and decreasing risk and cost. The New York Times considered use of such daylighting systems for their new 139,426 m2 (1.5 Mft2) headquarters building in downtown Manhattan.

In the initial phase of work, The New York Times employed a unique approach to create a competitive marketplace for daylighting systems and to address their concerns about risk by building a full-scale daylighting mockup and evaluating commercially-available products. This field test formed the strategic cornerstone for accelerating an industry response to the building owners' challenge to a sleepy market. A procurement specification was produced and bids were received that met The Times cost-effective criteria. The Times decided to proceed with using these innovative systems in their new building.

This next phase of work consisted of two distinct tasks: 1) to develop and use commissioning tools and procedures to insure that the automated shade and daylighting control systems operate as intended prior to occupancy; and 2) to estimate the peak demand savings resulting from different levels of demand response (DR) control strategies (from moderate to severe load curtailment) and then determine the financial implications given various DR programs offered by the local utility and New York Independent System Operator in the area.

Commissioning daylighting control systems is mandatory to insure that design intent is met, that the systems are tuned to optimal performance, and to eliminate problems and errors before occupants move in. Commissioning tools were developed and procedures were defined and then used to verify that the daylighting systems operated according to the technical specifications. For both lighting control and shading systems, the Times and the manufacturers were able to resolve most of the bugs and fine-tune the systems prior to occupancy.

The demand response (DR) strategies at the New York Times building involve unique state-of-the-art systems with dimmable ballasts, movable shades on the glass facade, and underfloor air HVAC. The process to develop the demand response strategies, the results of the EnergyPlus model, the activities to implement the DR strategies in the controls design at the New York Times Headquarters building and the evaluation of economics of participating in DR programs are presented and discussed. The DR simulation iv efforts for this building design are novel, with an innovative building owner evaluating DR and future DR program participation strategies during the design and construction phase using advanced simulation tools.

10aautomated daylighting controls10aautomated window shades10adaylighting10ademand response10aenergy-efficiency10avisual comfort1 aLee, Eleanor, S.1 aHughes, Glenn, D.1 aClear, Robert, D.1 aFernandes, Luis, L.1 aKiliccote, Sila1 aPiette, Mary, Ann1 aRubinstein, Francis, M.1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/daylighting-new-york-times-001259nas a2200157 4500008004100000245004400041210004300085260003400128300001200162490000800174520077700182100002200959700002200981700002001003856007801023 2007 eng d00aField Evaluation of Low-E Storm Windows0 aField Evaluation of LowE Storm Windows aClearwater Beach, FLc12/2007 a228-2360 v2773 a

A field evaluation comparing the performance of low emittance (low-e) storm windows with both standard clear storm windows and no storm windows was performed in a cold climate. Six homes with single pane windows were monitored over the period of one heating season. The homes were monitored with no storm windows and with new storm windows. The storm windows installed on four of the six homes included a hard coat, pyrolitic, low-e coating while the storm windows for the other two homes had traditional clear glass. Overall heating load reduction due to the storm windows was 13% with the clear glass and 21% with the low-e windows. Simple paybacks for the addition of the storm windows were 10 years for the clear glass and 4.5 years for the low-e storm windows.

1 aDrumheller, Craig1 aKohler, Christian1 aMinen, Stefanie uhttps://facades.lbl.gov/publications/field-evaluation-low-e-storm-windows03102nas a2200229 4500008004100000020002200041245008200063210006900145260004400214520234700258653001502605653001502620653002602635653001202661653001702673653001202690100002102702700002602723700002502749700002202774856007602796 2007 eng d a978-82-536-0970-600aState-of-the-Art Highly Insulating Window Frames - Research and Market Review0 aStateoftheArt Highly Insulating Window Frames Research and Marke aOlsobINTEF Building and Infrastructure3 a

This document reports the findings of a market and research review related to state-of-the-art highly insulating window frames. The market review focuses on window frames that satisfy the Passivhaus requirements (window U-value less or equal to 0.8 W/m2K), while other examples are also given in order to show the variety of materials and solutions that may be used for constructing window frames with a low thermal transmittance (U-value). The market search shows that several combinations of materials are used in order to obtain window frames with a low U-value. The most common insulating material seems to be Polyurethane (PUR), which is used together with most of the common structural materials such as wood, aluminum, and PVC.

The frame research review also shows examples of window frames developed in order to increase the energy efficiency of the frames and the glazings which the frames are to be used together with. The authors find that two main tracks are used in searching for better solutions. The first one is to minimize the heat losses through the frame itself. The result is that conductive materials are replaced by highly thermal insulating materials and air cavities. The other option is to reduce the window frame area to a minimum, which is done by focusing on the net energy gain by the entire window (frame, spacer and glazing). Literature shows that a window with a higher U-value may give a net energy gain to a building that is higher than a window with a smaller U-value. The net energy gain is calculated by subtracting the transmission losses through the window from the solar energy passing through the windows. The net energy gain depends on frame versus glazing area, solar factor, solar irradiance, calculation period and U-value.

The frame research review also discusses heat transfer modeling issues related to window frames. Thermal performance increasing measures, surface modeling, and frame cavity modeling are among the topics discussed. The review shows that the current knowledge gives the basis for improving the calculation procedures in the calculation standards. At the same time it is room for improvement within some areas, e.g. to fully understand the natural convection effects inside irregular vertical frame cavities (jambs) and ventilated frame cavities.

10aenergy use10aPassivhaus10athermal transmittance10aU-value10awindow frame10awindows1 aGustavsen, Arlid1 aJelle, Bjørn, Petter1 aArasteh, Dariush, K.1 aKohler, Christian uhttps://facades.lbl.gov/publications/state-art-highly-insulating-window03235nas a2200145 4500008004100000245014400041210006900185260002400254520264600278100002102924700002202945700002002967700002502987856007703012 2007 eng d00aTwo-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer in Horizontal Window Frames with Internal Cavities0 aTwoDimensional Computational Fluid Dynamics and Conduction Simul aDallas, TXc01/20073 a

This paper assesses the accuracy of the simplified frame cavity conduction/convection and radiation models presented in ISO 15099 and used in software for rating and labeling window products. Temperatures and U-factors for typical horizontal window frames with internal cavities are compared; results from Computational Fluid Dynamics (CFD) simulations with detailed radiation modeling are used as a reference.

Four different frames were studied. Two were made of polyvinyl chloride (PVC) and two of aluminum. For each frame, six different simulations were performed, two with a CFD code and four with a building-component thermal-simulation tool using the Finite Element Method (FEM). This FEM tool addresses convection using correlations from ISO 15099; it addressed radiation with either correlations from ISO 15099 or with a detailed, view-factor-based radiation model. Calculations were performed using the CFD code with and without fluid flow in the window frame cavities; the calculations without fluid flow were performed to verify that the CFD code and the building-component thermal-simulation tool produced consistent results. With the FEM-code, the practice of subdividing small frame cavities was examined, in some cases not subdividing, in some cases subdividing cavities with interconnections smaller than five millimeters (mm) (ISO 15099) and in some cases subdividing cavities with interconnections smaller than seven mm (a breakpoint that has been suggested in other studies). For the various frames, the calculated U-factors were found to be quite comparable (the maximum difference between the reference CFD simulation and the other simulations was found to be 13.2 percent). A maximum difference of 8.5 percent was found between the CFD simulation and the FEM simulation using ISO 15099 procedures. The ISO 15099 correlation works best for frames with high U-factors. For more efficient frames, the relative differences among various simulations are larger.

Temperature was also compared, at selected locations on the frames. Small differences was found in the results from model to model.

Finally, the effectiveness of the ISO cavity radiation algorithms was examined by comparing results from these algorithms to detailed radiation calculations (from both programs). Our results suggest that improvements in cavity heat transfer calculations can be obtained by using detailed radiation modeling (i.e. view-factor or ray-tracing models), and that incorporation of these strategies may be more important for improving the accuracy of results than the use of CFD modeling for horizontal cavities.

1 aGustavsen, Arlid1 aKohler, Christian1 aDalehaug, Arvid1 aArasteh, Dariush, K. uhttps://facades.lbl.gov/publications/two-dimensional-computational-fluid01663nas a2200325 4500008004100000024002100041245004200062210004200104260001200146520070300158653002500861653001300886653002500899653002700924653002200951653001800973653001600991653002301007653001901030100002101049700002701070700002201097700002901119700002201148700002401170700002201194700002401216700002101240856007601261 2006 eng d aCEC-500-2006-05200aAdvancement of Electrochromic Windows0 aAdvancement of Electrochromic Windows c04/20063 a

This guide provides consumer-oriented information about switchable electrochromic (EC) windows. Electrochromic windows change tint with a small applied voltage, providing building owners and occupants with the option to have clear or tinted windows at any time, irrespective of whether it's sunny or cloudy. EC windows can be manually or automatically controlled based on daylight, solar heat gain, glare, view, energy-efficiency, peak electricity demand response, or other criteria. Window controls can be integrated with other building systems, such as lighting and heating/cooling mechanical systems, to optimize interior environmental conditions, occupant comfort, and energy-efficiency.

10acommercial buildings10adaylight10adaylighting controls10aElectrochromic windows10aenergy efficiency10ahuman factors10apeak demand10aswitchable windows10avisual comfort1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E.1 aClear, Robert, D.1 aDiBartolomeo, Dennis, L.1 aKlems, Joseph, H.1 aFernandes, Luis, L.1 aWard, Gregory, J.1 aInkarojrit, Vorapat1 aYazdanian, Mehry uhttps://facades.lbl.gov/publications/advancement-electrochromic-windows02135nas a2200205 4500008004100000050001500041245005900056210005600115520147900171100002101650700002701671700002201698700002901720700002201749700002401771700002201795700002401817700002101841856006701862 2006 eng d aLBNL-5995000aA Design Guide for Early-Market Electrochromic Windows0 aDesign Guide for EarlyMarket Electrochromic Windows3 a

Switchable variable-tint electrochromic windows preserve the view out while modulating transmitted light, glare, and solar heat gains and can reduce energy use and peak demand. To provide designers objective information on the risks and benefits of this technology, this study offers data from simulations, laboratory tests, and a 2.5-year field test of prototype large-area electrochromic windows evaluated under outdoor sun and sky conditions. The study characterized the prototypes in terms of transmittance range, coloring uniformity, switching speed, and control accuracy. It also integrated the windows with a daylighting control system and then used sensors and algorithms to balance energy efficiency and visual comfort, demonstrating the importance of intelligent design and control strategies to provide the best performance. Compared to an efficient low-e window with the same daylighting control system, the electrochromic window showed annual peak cooling load reductions from control of solar heat gains of 19-26% and lighting energy use savings of 48-67% when controlled for visual comfort. Subjects strongly preferred the electrochromic window over the reference window, with preferences related to perceived reductions in glare, reflections on the computer monitor, and window luminance. The EC windows provide provided the benefit of greater access to view year-round. Though not definitive, findings can be of great value to building professionals.

1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E.1 aClear, Robert, D.1 aDiBartolomeo, Dennis, L.1 aKlems, Joseph, H.1 aFernandes, Luis, L.1 aWard, Gregory, J.1 aInkarojrit, Vorapat1 aYazdanian, Mehry uhttps://facades.lbl.gov/publications/design-guide-early-market01983nas a2200145 4500008004100000245012900041210006900170260003100239520140500270100002001675700002201695700002201717700002201739856007601761 2006 eng d00aDynamic Controls for Energy Efficiency and Demand Response: Framework Concepts and a New Construction Case Study in New York0 aDynamic Controls for Energy Efficiency and Demand Response Frame aPacific Grove, CAc06/20063 a

Many of today's advanced building control systems are designed to improve granularity of control for energy efficiency. Examples include direct digital controls for building heating, ventilation, and cooling systems (HVAC), and dimmable ballasts for continuous dimming for daylighting applications. This paper discusses recent research on the use of new and existing controls in commercial buildings for integrated energy efficiency and demand response (DR). The paper discusses the use of DR controls strategies in commercial buildings and provides specific details on DR control strategy design concepts for a new building in New York. We present preliminary results from EnergyPlus simulations of the DR strategies at the New York Times Headquarters building currently under construction. The DR strategies at the Times building involve unique state of the art systems with dimmable ballasts, movable shades on the glass facade, and underfloor air HVAC. The simulation efforts at this building are novel, with an innovative building owner considering DR and future DR program participation strategies during the design phase. This paper also discusses commissioning plans for the DR strategies. The trends in integration of various systems through the EMCS, master versus supervisory controls and dynamic operational modes concepts are presented and future research directions are outlined.

1 aKiliccote, Sila1 aPiette, Mary, Ann1 aWatson, David, S.1 aHughes, Glenn, D. uhttps://facades.lbl.gov/publications/dynamic-controls-energy-efficiency01885nas a2200169 4500008004100000050001500041245008600056210006900142260002700211520128600238100002501524700002401549700001901573700002201592700002201614856007901636 2006 eng d aLBNL-6124900aEvaluating Fenestration Products for Zero-Energy Buildings: Issues for Discussion0 aEvaluating Fenestration Products for ZeroEnergy Buildings Issues aCambridge, MAc08/20063 a

Computer modeling to determine fenestration product energy properties (U-factor, SHGC, VT) has emerged as the most cost-effective and accurate means to quantify them. Fenestration product simulation tools have been effective in increasing the use of low-e coatings and gas fills in insulating glass and in the widespread use of insulating frame designs and materials. However, for more efficient fenestration products (low heat loss products, dynamic products, products with non-specular optical characteristics, light redirecting products) to achieve widespread use, fenestration modeling software needs to be improved.

This paper addresses the following questions:

1) Are the current properties (U, SHGC, VT) calculated sufficient to compare and distinguish between windows suitable for Zero Energy Buildings and conventional window products? If not, what data on the thermal and optical performance, on comfort, and on peak demand of windows is needed.

2) Are the algorithms in the tools sufficient to model the thermal and optical processes? Are specific heat transfer and optical effects not accounted for? Is the existing level of accuracy enough to distinguish between products designed for Zero Energy Buildings? Is the current input data adequate?

1 aArasteh, Dariush, K.1 aCurcija, Dragan, C.1 aHuang, Yu, Joe1 aHuizenga, Charlie1 aKohler, Christian uhttps://facades.lbl.gov/publications/evaluating-fenestration-products-zero02228nas a2200205 4500008004100000245010200041210006900143260003300212490001600245520148700261653003701748653002201785653002501807100002101832700002901853700002201882700002101904700002701925856007001952 2006 eng d00aMonitored Energy Performance of Electrochromic Windows Controlled for Daylight and Visual Comfort0 aMonitored Energy Performance of Electrochromic Windows Controlle aQuebec City, Canadac10/20060 v112 Issue 23 a

A 20-month field study was conducted to measure the energy performance of south-facing large-area tungsten-oxide absorptive electrochromic (EC) windows with a broad switching range in a private office setting. The EC windows were controlled by a variety of means to bring in daylight while minimizing window glare. For some cases, a Venetian blind was coupled with the EC window to block direct sun. Some tests also involved dividing the EC window wall into zones where the upper EC zone was controlled to admit daylight while the lower zone was controlled to prevent glare yet permit view. If visual comfort requirements are addressed by EC control and Venetian blinds, a 2-zone EC window configuration provided average daily lighting energy savings of 10-15% compared to the reference case with fully lowered Venetian blinds. Cooling load reductions were 0-3%. If the reference case assumes no daylighting controls, lighting energy savings would be 44-11%. Peak demand reductions due to window cooling load, given a critical demand-response mode, were 19-26% maximum on clear sunny days. Peak demand reductions in lighting energy use were 0% or 72-100% compared to a reference case with and without daylighting controls, respectively. Lighting energy use was found to be very sensitive to how glare and sun is controlled. Additional research should be conducted to fine-tune EC control for visual comfort based on solar conditions so as to increase lighting energy savings.

10abuilding automation and controls10aBuilding envelope10acommercial buildings1 aLee, Eleanor, S.1 aDiBartolomeo, Dennis, L.1 aKlems, Joseph, H.1 aYazdanian, Mehry1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/monitored-energy-performance01286nas a2200169 4500008004100000050001500041245006100056210006100117260002400178520073100202100002500933700001800958700001900976700002200995700002001017856007901037 2006 eng d aLBNL-5919000aPerformance Criteria for Residential Zero Energy Windows0 aPerformance Criteria for Residential Zero Energy Windows aDallas, TXc01/20073 a

This paper shows that the energy requirements for today's typical efficient window products (i.e. ENERGY STAR products) are significant when compared to the needs of Zero Energy Homes (ZEHs). Through the use of whole house energy modeling, typical efficient products are evaluated in five US climates and compared against the requirements for ZEHs. Products which meet these needs are defined as a function of climate. In heating dominated climates, windows with U-factors of 0.10 Btu/hr-ft2-F (0.57 W/m2-K) will become energy neutral. In mixed heating/cooling climates a low U-factor is not as significant as the ability to modulate from high SHGCs (heating season) to low SHGCs (cooling season).

1 aArasteh, Dariush, K.1 aGoudey, Howdy1 aHuang, Yu, Joe1 aKohler, Christian1 aMitchell, Robin uhttps://facades.lbl.gov/publications/performance-criteria-residential-zero01925nas a2200241 4500008004100000245007500041210006900116260001200185300001400197490000800211520114900219653003001368653003801398653001601436653001901452653003701471100001901508700002001527700002201547700002201569700002101591856007101612 2006 eng d00aPlasma biasing to control the growth conditions of diamond-like carbon0 aPlasma biasing to control the growth conditions of diamondlike c c01/2007 a4628-46320 v2013 a

It is well known that the structure and properties of diamond-like carbon, and in particular the sp3/sp2 ratio, can be controlled by the energy of the condensing carbon ions or atoms. In many practical cases, the energy of ions arriving at the surface of the growing film is determined by the bias applied to the substrate. The bias causes a sheath to form between substrate and plasma in which the potential difference between plasma potential and surface potential drops. In this contribution, we demonstrate that the same results can be obtained with grounded substrates by shifting the plasma potential. This plasma biasing (as opposed to substrate biasing) is shown to work well with pulsed cathodic carbon arcs, resulting in tetrahedral amorphous carbon (ta-C) films that are comparable to the films obtained with the conventional substrate bias. To verify the plasma bias approach, ta-C films were deposited by both conventional and plasma bias and characterized by transmission electron microscopy (TEM) and electron energy loss spectrometry (EELS). Detailed data for comparison of these films are provided.

10aDiamond-like carbon films10aElectron energy loss spectroscopy10aPlasma bias10aSubstrate bias10atransmission electron microscopy1 aAnders, André1 aPasaja, Nitisak1 aLim, Sunnie, H.N.1 aPetersen, Tim, C.1 aKeast, Vicki, J. uhttps://facades.lbl.gov/publications/plasma-biasing-control-growth01066nas a2200157 4500008004100000050001500041245006800056210006800124520054600192100001900738700001800757700001700775700002000792700002200812856007400834 2006 eng d aLBNL-5962100aSmoothing of ultrathin silver films by transition metal seeding0 aSmoothing of ultrathin silver films by transition metal seeding3 a

The nucleation and coalescence of silver islands on coated glass was investigated by in-situ measurements of the sheet resistance. Sub-monolayer amounts of transition metals (Nb, Ti, Ni, Cr, Zr, Ta, and Mo) were deposited prior to the deposition of silver. It was found that some, but not all, of the transition metals lead to coalescence of silver at nominally thinner films with smoother topology. The smoothing effect of the transition metal at sub-monolayer thickness can be explained by a thermodynamic model of surface energies.

1 aAnders, André1 aByon, Eungsun1 aKim, Dong-Ho1 aFukuda, Kentaro1 aLim, Sunnie, H.N. uhttps://facades.lbl.gov/publications/smoothing-ultrathin-silver-films00380nas a2200085 4500008004100000245008600041210006900127100002000196856007800216 2006 eng d00aTechnical Note: The New York Times Demand Response Strategies for the HVAC System0 aTechnical Note The New York Times Demand Response Strategies for1 aKurtz, Flack, + uhttps://facades.lbl.gov/publications/technical-note-new-york-times-demand01965nas a2200169 4500008004100000050001500041245010300056210006900159260002500228490000800253520136800261100002101629700002501650700002201675700002401697856007401721 2005 eng d aLBNL-6125000aTwo-Dimension Conduction and CFD Simulations for Heat Transfer in Horizontal Window Frame Cavities0 aTwoDimension Conduction and CFD Simulations for Heat Transfer in aOrlando, FLc02/20050 v1113 a

Accurately analyzing heat transfer in window frames and glazings is important for developing and characterizing the performance of highly insulating window products. This paper uses computational fluid dynamics (CFD) modeling to assess the accuracy of the simplified frame cavity conduction/convection models presented in ISO 15099 and used in software for rating and labeling window products. Three representative complex cavity cross-section profiles with varying dimensions and aspect ratios are examined. The results presented support the ISO 15099 rule that complex cavities with small throats should be subdivided; however, our data suggest that cavities with throats smaller than 7 mm should be subdivided, in contrast to the ISO 15099 rule, which places the break point at 5 mm. The agreement between CFD modeling results and the results of the simplified models is moderate for the heat transfer rates through the cavities. The differences may be a result of the underlying ISO 15099 Nusselt number correlations being based on studies where cavity height/length aspect ratios were smaller than 0.5 and greater than 5 (with linear interpolation assumed in between). The results presented here are for horizontal frame members because convection in vertical jambs involves very different aspect ratios that require three-dimensional CFD simulations.

1 aGustavsen, Arlid1 aArasteh, Dariush, K.1 aKohler, Christian1 aCurcija, Dragan, C. uhttps://facades.lbl.gov/publications/two-dimension-conduction-and-cfd01808nas a2200241 4500008004100000022001500041245010500056210006900161260001200230300001200242490000700254520105000261653001501311653002401326653002201350653002501372653002101397100001801418700001801436700001901454700001901473856007401492 2004 eng d a0093-3813 00aEffect of Ion Mass and Charge State on Transport Vacuum Arc Plasmas Through a Biased Magnetic Filter0 aEffect of Ion Mass and Charge State on Transport Vacuum Arc Plas c04/2004 a433-4390 v323 a

The effect of ion mass and charge state on plasma transport through a 90 deg.-curved magnetic filter is experimentally investigated using a pulsed cathodic arc source. Graphite, copper, and tungsten were selected as test materials. The filter was a bent copper coil biased via the voltage drop across a low-ohm, selfbias resistor. Ion transport is accomplished via a guiding electric field, whose potential forms a trough shaped by the magnetic guiding field of the filter coil. Evaluation was done by measuring the filtered ion current and determination of the particle system coefficient, which can be defined as the ratio of filtered ion current, divided by the mean ion charge state, to the arc current. It was found that the ion current and particle system coefficient decreased as the mass-to-charge ratio of ions increased. This result can be qualitatively interpreted by a very simple model of ion transport that is based on compensation of the centrifugal force by the electric force associated with the guiding potential trough.

10aArc plasma10acathodic vacuum arc10aion charge states10amacroparticle filter10aplasma transport1 aByon, Eungsun1 aKim, Jong-Kuk1 aKwon, Sik-Chol1 aAnders, André uhttps://facades.lbl.gov/publications/effect-ion-mass-and-charge-state01739nas a2200157 4500008004100000050001500041245006000056210005700116260001200173300000700185520124800192100002201440700001801462700002501480856007601505 2004 eng d aLBNL-5607500aA First-Generation Prototype Dynamic Residential Window0 aFirstGeneration Prototype Dynamic Residential Window c10/2004 a113 a

We present the concept for a "smart" highly efficient dynamic window that maximizes solar heat gain during the heating season and minimizes solar heat gain during the cooling season in residential buildings. We describe a prototype dynamic window that relies on an internal shade, which deploys automatically in response to solar radiation and temperature. This prototype was built at Lawrence Berkeley National Laboratory from commercially available "off-the-shelf" components. It is a stand-alone, standard-size product, so it can be easily installed in place of standard window products. Our design shows promise for near-term commercialization. Improving thermal performance of this prototype by incorporating commercially available highly efficient glazing technologies could result in the first window that could be suitable for use in zero-energy homes. The units predictable deployment of shading could help capture energy savings that are not possible with manual shading. Installation of dynamically shaded windows in the field will allow researchers to better quantify the energy effects of shades, which could lead to increased efficiency in the sizing of heating, ventilation, and air conditioning equipment for residences.

1 aKohler, Christian1 aGoudey, Howdy1 aArasteh, Dariush, K. uhttps://facades.lbl.gov/publications/first-generation-prototype-dynamic01448nas a2200169 4500008004100000050001500041245004400056210004300100520093100143100002001074700002201094700002501116700001801141700002201159700002401181856007301205 2003 eng d aLBNL-4825500aTHERM 5/WINDOW 5 NFRC Simulation Manual0 aTHERM 5WINDOW 5 NFRC Simulation Manual3 a

This document, the THERM 5 / WINDOW 5 NFRC Simulation Manual, discusses how to use the THERM and WINDOW programs to model products for NFRC certified simulations and assumes that the user is already familiar with those programs. In order to learn how to use these programs, it is necessary to become familiar with the material in both the THERM Users Manual and the WINDOW Users Manual. In general, this manual references the Users Manuals rather than repeating the information.

If there is a conflict between either of the User Manual and this THERM 5 / WINDOW 5 NFRC Simulation Manual, the THERM 5 / WINDOW 5 NFRC Simulation Manual takes precedence. In addition, if this manual is in conflict with any NFRC standards, the standards take precedence. For example, if samples in this manual do not follow the current taping and testing NFRC standards, the standards not the samples in this manual, take precedence.

1 aMitchell, Robin1 aKohler, Christian1 aArasteh, Dariush, K.1 aCarmody, John1 aHuizenga, Charlie1 aCurcija, Dragan, C. uhttps://facades.lbl.gov/publications/therm-5window-5-nfrc-simulation02348nas a2200157 4500008004100000050001500041245015700056210006900213260002500282520171200307100002102019700002202040700002502062700002402087856007902111 2003 eng d aLBNL-5250900aTwo-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer in Window Frames with Internal Cavities - Part 1: Cavities Only0 aTwoDimensional Computational Fluid Dynamics and Conduction Simul aOrlando, FLc02/20053 a

Accurately analyzing heat transfer in window frame cavities is essential for developing and characterizing the performance of highly insulating window products. Window frame thermal performance strongly influences overall product thermal performance because framing materials generally perform much more poorly than glazing materials. This paper uses Computational Fluid Dynamics (CFD) modeling to assess the accuracy of the simplified frame cavity conduction/convection models presented in ISO 15099 and used in software for rating and labeling window products. (We do not address radiation heat-transfer effects.) We examine three representative complex cavity cross-section profiles with varying dimensions and aspect ratios. Our results support the ISO 15099 rule that complex cavities with small throats should be subdivided; however, our data suggest that cavities with throats smaller than seven millimeters (mm) should be subdivided, in contrast to the ISO 15099 rule, which places the break point at five mm. The agreement between CFD modeling results and the results of the simplified models is moderate. The differences in results may be a result of the underlying ISO correlations being based on studies where cavity height/length (H/L) aspect ratios were smaller than 0.5 and greater than five (with linear interpolation assumed in between). The results presented here are for horizontal frame members because convection in vertical jambs involves very different aspect ratios that require three-dimensional CFD simulations. Ongoing work focuses on quantifying the exact effect on window thermal performance indicators of using the ISO 15099 approximations in typical real window frames.

1 aGustavsen, Arlid1 aKohler, Christian1 aArasteh, Dariush, K.1 aCurcija, Dragan, C. uhttps://facades.lbl.gov/publications/two-dimensional-computational-fluid-002180nas a2200157 4500008004100000050001500041245005000056210004900106520167200155100002101827700002701848700002201875700002301897700002401920856007801944 2002 eng d aLBNL-5050200aHigh-Performance Commercial Building Façades0 aHighPerformance Commercial Building Façades3 a

There is a significant and growing interest in the use of highly-glazed façades in commercial buildings. Large portions of the façade or even the entire façade are glazed with relatively high transmittance glazing systems, and typically with some form of sun control as well. With origins in Europe the trend is expanding to other regions, including the United States. A subset of these designs employ a second layer creating a double envelope system, which can then accommodate additional venting and ventilation practices. The stated rationale for use of the these design approaches varies but often includes a connection to occupant benefits as well as sustainable design associated with daylighting and energy savings. As with many architectural trends, understanding the reality of building performance in the field as compared to design intent is often difficult to ascertain. We have been particularly interested in this emerging trend because prior simulation studies have shown that it should be technically possible to produce an all-glass façade with excellent performance although it is not a simple challenge. The published solutions are varied enough and sufficiently complex that we undertook a year-long international review of advanced façades to better understand the capabilities and limitations of existing systems and the tools and processes used to create them. This is also intended to create a framework for addressing the missing tools, technologies, processes and data bases that will be needed to turn the promise of advanced façades into realities. This summary, available as a PDF file and a web site, reports those findings.

1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E.1 aKohler, Christian1 aBazjanac, Vladimir1 aInkarojrit, Vorapat uhttps://facades.lbl.gov/publications/high-performance-commercial-building01168nas a2200133 4500008004100000050001500041245004900056210004900105260002900154490001600183520073800199100002200937856007500959 2002 eng d aLBNL-5145300aMeasured Winter Performance of Storm Windows0 aMeasured Winter Performance of Storm Windows aKansas City, MOc07/20030 v109, Part 23 a

Direct comparison measurements were made between various prime/storm window combinations and a well-weatherstripped, single-hung replacement window with a low-E selective glazing. Measurements were made using an accurate outdoor calorimetric facility with the windows facing north. The double-hung prime window was made intentionally leaky. Nevertheless, heat flows due to air infiltration were found to be small, and performance of the prime/storm combinations was approximately what would be expected from calculations that neglect air infiltration. Prime/low-E storm window combinations performed very similarly to the replacement window. Interestingly, solar heat gain was not negligible, even in north-facing orientation.

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/measured-winter-performance-storm00811nam a2200241 4500008004100000050001500041245007900056210006900135100001600204700002300220700001900243700002500262700002000287700001700307700002000324700003000344700002000374700002100394700002000415700002800435700002700463856007900490 2001 eng d aLBNL-4749300aDaylight in Buildings. A Source Book on Daylighting Systems and Components0 aDaylight in Buildings A Source Book on Daylighting Systems and C1 aRuck, Nancy1 aAschehoug, Øyvind1 aAydinli, Sirri1 aChristoffersen, Jens1 aCourret, Gilles1 aEdmonds, Ian1 aJakobiak, Roman1 aKischkoweit-Lopin, Martin1 aKlinger, Martin1 aLee, Eleanor, S.1 aMichel, Laurent1 aScartezzini, Jean-Louis1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/daylight-buildings-source-book-daylighting-systems02156nas a2200169 4500008004100000050001500041245008000056210006900136260003400205520156000239100002501799700002001824700002201844700002201866700002401888856007401912 2001 eng d aLBNL-4814700aImproving Information Technology to Maximize Fenestration Energy Efficiency0 aImproving Information Technology to Maximize Fenestration Energy aClearwater Beach, FLc12/20013 a

Annual heating and cooling energy loads through fenestration products in both residential and commercial buildings are a significant fraction of national energy requirements. In the residential sector, 1.34 and 0.37 quads are required for heating and cooling respectively (DOE Core Data Book, 2000). In commercial buildings, cooling energy use to compensate for fenestration product solar heat gain is estimated at 0.39 quads; heating energy use to compensate for heat loss through fenestration products is estimated at 0.19 quads. Advanced products offer the potential to reduce these energy uses by at least 50% (Frost et. al. 1993). Potential electric lighting savings from fenestration products are estimated at 0.4 quads if daylight can be used effectively so that electric lighting in commercial building perimeter zones can be reduced.

Software has begun to make an impact on the design and deployment of efficient fenestration products by making fenestration product performance ratings widely available. These ratings, which are determined in part using software programs such as WINDOW/THERM/Optics, VISION/FRAME, and WIS, can now easily be used by architects, engineers, professional fenestration product specifiers, and consumers. Information on the properties of fenestration products has also influenced state and national codes (IECC, ASHRAE 90.1) and aided voluntary market transformation programs, such as the Efficient Windows Collaborative and the Energy Star Windows program, which promote efficient fenestration products.

1 aArasteh, Dariush, K.1 aMitchell, Robin1 aKohler, Christian1 aHuizenga, Charlie1 aCurcija, Dragan, C. uhttps://facades.lbl.gov/publications/improving-information-technology01286nas a2200145 4500008004100000050001500041245005500056210005500111260002500166300001200191490001600203520082500219100002201044856007401066 2001 eng d aLBNL-4883500aSolar Heat Gain through a Skylight in a Light Well0 aSolar Heat Gain through a Skylight in a Light Well aChicago, ILc01/2003 a512-5240 v108, Part 13 a

Detailed heat flow measurements on a skylight mounted on a light well of significant depth are presented. It is shown that during the day much of the solar energy that strikes the walls of the well does not reach the space below. Instead, this energy is trapped in the stratified air of the light well and eventually either conducted through the walls of the well or back out through the skylight. The standard model for predicting fenestration heat transfer does not agree with the measurements when it is applied to the skylight/well combination as a whole (the usual practice), but does agree reasonably well when it is applied to the skylight alone, using the well air temperature near the skylight. A more detailed model gives good agreement. Design implications and future research directions are discussed.

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/solar-heat-gain-through-skylight01355nas a2200193 4500008004100000245005500041210005400096260001200150300001400162490000700176520076500183100002700948700002400975700002500999700002101024700002001045700002301065856007301088 2001 eng d00aSwitchable Mirrors Based on Nickel-Magnesium Films0 aSwitchable Mirrors Based on NickelMagnesium Films c05/2001 a3047-30490 v783 a

An electrochromic mirror electrode based on reversible uptake of hydrogen in nickel magnesium alloy films is reported. Thin, magnesium-rich Ni-Mg films prepared on glass substrates by cosputtering from Ni and Mg targets are mirror-like in appearance and have low visible transmittance. Upon exposure to hydrogen gas or on cathodic polarization in alkaline electrolyte, the films take up hydrogen and become transparent. When hydrogen is removed, the mirror properties are recovered. The transition is believed to result from reversible formation of Mg2NiH4 and MgH2. A thin overlayer of palladium was found to enhance the kinetics of hydrogen insertion and extraction, and to protect the metal surface against oxidation.

1 aRichardson, Thomas, J.1 aSlack, Jonathan, L.1 aArmitage, Robert, D.1 aKostecki, Robert1 aFarangis, Baker1 aRubin, Michael, D. uhttps://facades.lbl.gov/publications/switchable-mirrors-based-nickel01132nas a2200157 4500008004100000245008800041210006900129260003200198300001200230490001600242520057600258100002200834700002500856700002000881856007300901 2001 eng d00aTHERM Simulations of Window Indoor Surface Temperatures for Predicting Condensation0 aTHERM Simulations of Window Indoor Surface Temperatures for Pred aAtlantic City, NJc01/ 2002 a593-5990 v109, Part 13 a

As part of a round robin project, the performance of two wood windows and a Calibrated Transfer Standard was modeled using the THERM heat-transfer simulation program. The resulting interior surface temperatures can be used as input to condensation resistance rating procedures. The Radiation and Condensation Index features within THERM were used to refine the accuracy of simulation results. Differences in surface temperatures between the Basic calculations and those incorporating the Radiation and/or Condensation Index features are demonstrated and explained.

1 aKohler, Christian1 aArasteh, Dariush, K.1 aMitchell, Robin uhttps://facades.lbl.gov/publications/therm-simulations-window-indoor00496nas a2200133 4500008004100000245006800041210006700109100002000176700002200196700002500218700002200243700002400265856007300289 2001 eng d00aWINDOW 5.0 User Manual for Analyzing Window Thermal Performance0 aWINDOW 50 User Manual for Analyzing Window Thermal Performance1 aMitchell, Robin1 aKohler, Christian1 aArasteh, Dariush, K.1 aHuizenga, Charlie1 aCurcija, Dragan, C. uhttps://facades.lbl.gov/publications/window-50-user-manual-analyzing01152nas a2200109 4500008004100000050001500041245011700056210006900173520069900242100002200941856007900963 2000 eng d aLBNL-4668200aSolar Heat Gain Through Fenestrations Containing Shading: Procedures for Estimating Performace from Minimal Data0 aSolar Heat Gain Through Fenestrations Containing Shading Procedu3 a

The computational methods for calculating the properties of glazing systems containing shading from the properties of their components have been developed, but the measurement standards and property data bases necessary to apply them have not. It is shown that with a drastic simplifying assumption these methods can be used to calculate system solar-optical properties and solar heat gain coefficients for arbitrary glazing systems, while requiring limited data about the shading. Detailed formulas are presented, and performance multipliers are defined for the approximate treatment of simple glazings with shading. As higher accuracy is demanded, the formulas become very complicated.

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/solar-heat-gain-through-fenestrations01204nas a2200193 4500008004100000245003700041210003600078260001200114300000800126520064300134100002000777700002200797700002500819700002900844700002200873700002400895700001800919856007300937 2000 eng d00aTHERM 2.1 NFRC Simulation Manual0 aTHERM 21 NFRC Simulation Manual c07/2000 a2603 a

This document, the THERM 2.1 NFRC Simulation Manual, discusses how to use THERM to model products for NFRC certified simulations and assumes that the user is already familiar with the THERM program. In order to learn how to use THERM, it is necessary to become familiar with the material in the THERM User's Manual.

In general, this manual references the THERM User's Manual rather than repeating the information.

If there is a conflict between the THERM User's Manual and the THERM 2.1 NFRC Simulation Manual, the THERM 2.1 NFRC Simulation Manual takes precedence.

1 aMitchell, Robin1 aKohler, Christian1 aArasteh, Dariush, K.1 aFinlayson, Elizabeth, U.1 aHuizenga, Charlie1 aCurcija, Dragan, C.1 aCarmody, John uhttps://facades.lbl.gov/publications/therm-21-nfrc-simulation-manual01115nas a2200121 4500008004100000245004100041210004000082260003600122490001600158520072200174100002200896856007500918 2000 eng d00aU-Values of Flat and Domed Skylights0 aUValues of Flat and Domed Skylights aMinneapolis, Minnesotac06/20000 v106, Part 23 a

Data from nighttime measurements of the net heat flow through several types of skylights is presented. A well-known thermal test facility was reconfigured to measure the net heat flow through the bottom of a skylight/light well combination. Use of this data to determine the U-factor of the skylight is considerably more complicated than the analogous problem of a vertical fenestration contained in a test mask. Correction of the data for heat flow through the skylight well surfaces and evidence for the nature of the heat transfer between the skylight and the bottom of the well is discussed. The resulting measured U-values are presented and compared with calculations using the WINDOW4 and THERM programs.

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/u-values-flat-and-domed-skylights01238nas a2200169 4500008004100000050001500041245008000056210006900136260002700205520065300232100002500885700001900910700002000929700002200949700002200971856007500993 1999 eng d aLBNL-4402000aA Database of Window Annual Energy Use in Typical North American Residences0 aDatabase of Window Annual Energy Use in Typical North American R aDallas, Texasc02/20003 a

This paper documents efforts by the National Fenestration Rating Council to develop a database on annual energy impacts of windows in a typical new, single family, single story residence in various U.S. and Canadian climates. The result is a database of space heating and space cooling energies for 14 typical windows in 52 North American climates. (Future efforts will address the effects of skylights.) This paper describes how this database was created, documents the assumptions used in creating this database, elaborates on assumptions, which need further research, examines the results, and describes the possible uses of the database.

1 aArasteh, Dariush, K.1 aHuang, Yu, Joe1 aMitchell, Robin1 aClear, Robert, D.1 aKohler, Christian uhttps://facades.lbl.gov/publications/database-window-annual-energy-use00858nas a2200133 4500008004100000050001500041245006800056210006800124300001100192490000700203520041500210100002200625856007700647 1999 eng d aLBNL-4282500aNet Energy Performance Measurements on Electrochromic Skylights0 aNet Energy Performance Measurements on Electrochromic Skylights a93-1020 v333 a

Tests of skylights made from prototype electrochromic glazings were performed in a room-sized calorimetric test facility under ambient outdoor summer conditions in Reno, NV. The test methodology and the resultant measurements of skylight heat flows and temperatures with their diurnal variations are presented. Special test issues relating to the dynamic switchable nature of the glazings are discussed.

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/net-energy-performance-measurements02296nas a2200169 4500008004100000024001100041245004100052210004100093260001200134520179000146100002201936700002901958700002201987700002002009700002102029856007602050 1999 eng d aBS 42200aToward a Virtual Building Laboratory0 aToward a Virtual Building Laboratory c03/19993 a

Buildings account for about one-third of all energy used in the US and about two-thirds of all electricity, with associated environmental impacts.(EIA 1996) After more than 20 years of DOE-supported research universities and national laboratories, a great deal is known about the energy performance of buildings and especially their components and subsystems. The development and market introduction of improved energy efficient technology, such as low-E windows and electronic ballasts, have helped reduce energy use, and the resultant savings will increase, as use of the new technologies becomes more widespread. A variety of approaches to speed market penetration have been and are being pursued, including information dissemination, research to evaluate performance and development of computer tools for making energy performance simulations available to architects and engineers at the earliest design stages. Public-domain computer building energy simulation models, (BLAST_Support_Office 1992; Winkelmann, Birdsall et al. 1993) a controversial idea 20 years ago, have been extremely successful in facilitating the design of more energy-efficient buildings and providing the technical basis for improved state building codes, federal guidelines, and voluntary standards. But the full potential of savings, estimated at 50% of current consumption or $100 billion/year, (Bevington and Rosenfeld 1990; Todesco 1996; Holdren 1997; Kolderup and Syphers 1997; ORNL, LBNL et al. 1997) will require that architects and engineers take an integrated look at buildings beginning in the early design phase, with increasing use of sophisticated, complex and interrelated building systems. This puts a greater burden on the designer and engineer to make accurate engineering decisions.

1 aKlems, Joseph, H.1 aFinlayson, Elizabeth, U.1 aOlsen, Thomas, H.1 aBanks, David, W1 aPallis, Jani, M. uhttps://facades.lbl.gov/publications/toward-virtual-building-laboratory02282nas a2200229 4500008004100000245008200041210006900123260001200192300001000204490000700214520155300221653002501774653002801799653001501827100002301842700001701865700002701882700001901909700002301928700002401951856007701975 1998 eng d00aElectrochromic lithium nickel oxide by pulsed laser deposition and sputtering0 aElectrochromic lithium nickel oxide by pulsed laser deposition a c07/1998 a59-660 v543 a

Thin films of lithium nickel oxide were deposited by sputtering and pulsed laser deposition (PLD) from targets of pressed LiNiO2 powder. The composition and structure of these films were analyzed using a variety of techniques, such as nuclear-reaction analysis, Rutherford backscattering spectrometry (RBS), X-ray diffraction, infrared spectroscopy, and atomic-force microscopy. Crystalline structure, surface morphology and chemical composition of LixNi1−xO thin films depend strongly on deposition oxygen pressure, temperature as well as substrate–target distance. The films produced at temperatures lower than 600°C spontaneously absorb CO2 and H2O at their surface once they are exposed to the air. The films deposited at 600°C proved to be stable in air over a long period. Even at room temperature the PLD films are denser and more stable than sputtered films. RBS determined the composition of the best films to be Li0.5Ni0.5O deposited by PLD at 60 mTorr O2 pressure. Electrochemical tests show that the films exhibit excellent reversibility in the range 1.0–3.4 V versus lithium. Electrochemical formatting which is used to develop electrochromism in other films is not needed for the stoichiometric films. The optical transmission range is almost 70% at 550 nm for 150 nm-thick films. Devices made from these films were analyzed using novel reference electrodes and by disassembling after cycling.

10aLithium nickel oxide10apulsed laser deposition10asputtering1 aRubin, Michael, D.1 aWen, Shi-Jie1 aRichardson, Thomas, J.1 aKerr, John, B.1 avon Rottkay, Klaus1 aSlack, Jonathan, L. uhttps://facades.lbl.gov/publications/electrochromic-lithium-nickel-oxide01350nas a2200181 4500008004100000245007700041210006900118260001200187300001400199490000700213520076000220100002100980700001901001700002501020700002301045700002301068856007701091 1998 eng d00aOptical Constants of Sputter-Deposited Ti-Ce Oxide and Zr-Ce Oxide Films0 aOptical Constants of SputterDeposited TiCe Oxide and ZrCe Oxide  c09/1998 a5993-60010 v373 a

Films of Ti oxide, Zr oxide, Ce oxide, Ti-Ce oxide, and Zr-Ce oxide were made by means of reactive dc magnetron sputtering in a multitarget arrangement. The films were characterized by x-ray diffraction and electrochemical measurements, both techniques being firmly connected to stoichiometric information. The optical constants n and k were evalued from spectrophotometry and from variable-angle spectroscopic ellipsometry. The two analyses gave consistent results. It was found that n for the mixed-oxide films varied smoothly between the values for the pure oxides, whereas k in the band-gap range showed characteristic differences between Ti-Ce oxide and Zr-Ce oxide. It is speculated that this difference is associated with structural effects.

1 aVeszelei, Monica1 aKullman, Lisen1 aGranqvist, Claes, G.1 avon Rottkay, Klaus1 aRubin, Michael, D. uhttps://facades.lbl.gov/publications/optical-constants-sputter-deposited01829nas a2200169 4500008004100000050001500041245008200056210006900138260003900207520123000246100002401476700002201500700001801522700001901540700002501559856007501584 1998 eng d aLBNL-4135200aRapid field testing of low-emittance coated glazings for product verification0 aRapid field testing of lowemittance coated glazings for product  aClearwater Beach, Floridac12/19983 a

This paper analyzes prospects for developing a test device suitable for field verification of the types of low-emittance (low-e) coatings present on high-performance window products. Test devices are currently available that can simply detect the presence of low-e coatings and that can measure other important characteristics of high-performance windows, such as the thickness of glazing layers or the gap in dual glazings. However, no devices have yet been developed that can measure gas concentrations or distinguish among types of coatings. This paper presents two optical methods for verification of low-e coatings. The first method uses a portable, fiber-optic spectrometer to characterize spectral reflectances from 650 to 1,100 nm for selected surfaces within an insulated glazing unit (IGU). The second method uses an infrared-light-emitting diode and a phototransistor to evaluate the aggregate normal reflectance of an IGU at 940 nm. Both methods measure reflectance in the near (solar) infrared spectrum and are useful for distinguishing between regular and spectrally selective low-e coatings. The infrared-diode/phototransistor method appears promising for use in a low-cost, hand-held field test device.

1 aGriffith, Brent, T.1 aKohler, Christian1 aGoudey, Howdy1 aTurler, Daniel1 aArasteh, Dariush, K. uhttps://facades.lbl.gov/publications/rapid-field-testing-low-emittance01287nas a2200133 4500008004100000050001500041245005500056210005400111260003100165490001600196520084400212100002201056856007501078 1997 eng d aLBNL-4044800aGreenhouse Window U-Factors Under Field Conditions0 aGreenhouse Window UFactors Under Field Conditions aSan Francisco, CAc01/19980 v104, Part 13 a

Field measurements of U-factor are reported for two projecting greenhouse windows, each paired with a picture window of comparable insulation level during testing. A well-known calorimetric field test facility was used to make the measurements. The time-varying U-factors obtained are related to measurements of exterior conditions. For one of the greenhouse windows, which was the subject of a published laboratory hotbox test and simulation study, the results are compared with published test and simulation data and found to be in disagreement. Data on interior and exterior film coefficients are presented, and it is shown that the greenhouse window has a significantly lower interior film coefficient than a conventional window under the same interior conditions. This is advanced as a possible explanation of the disagreement.

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/greenhouse-window-u-factors-under01883nas a2200253 4500008004100000050001500041245008500056210006900141260003000210520107000240653001301310653002001323653004101343653001501384653002201399653001801421653000901439100002301448700002701471700002301498700002401521700001901545856006501564 1997 eng d aLBNL-4155000aInfluence of stoichiometry on the electrochromic cerium-titanium oxide compounds0 aInfluence of stoichiometry on the electrochromic ceriumtitanium  aHonolulu, Hawaiic11/19973 a

CeO2-TiO2 finds use as passive counter-electrode in electrochromic devices. Thin films were produced by dc-sputtering in a wide range of compositions. Influence of total pressure and oxygen partial pressure on the optical constants of TiO2 was investigated. Slightly substoichiometric TiO2 films exhibit a red-shift of the bandgap. The TiO2 content in the compound essentially determines the degree of cathodical coloring upon Li+ intercalation. However, pure TiO2 films with comparable visible transmittance in the clear state behave differently during electrochemical cycling depending on oxygen stoichiometry. Films that are deposited at higher total pressure are more oxygen rich and require initial formatting until current voltage cycles become stable. CeO2-TiO2 films of intermediate compositions have the relatively highest charge capacity. Comparison with atomic force microscopy indicates a correlation of small grain size with high charge capacity.

10aband gap10acharge capacity10aelectrochromic cerium titanium oxide10agrain size10aoptical constants10arms roughness10atio21 avon Rottkay, Klaus1 aRichardson, Thomas, J.1 aRubin, Michael, D.1 aSlack, Jonathan, L.1 aKullman, Lisen uhttps://facades.lbl.gov/publications/influence-stoichiometry01711nas a2200229 4500008004100000245008000041210006900121490000800190520094800198100002501146700002301171700003101194700001901225700002101244700002701265700001901292700002901311700002301340700002101363700002101384856007601405 1997 eng d00aPressure Controlled GaN MBE Growth Using a Hollow Anode Nitrogen Ion Source0 aPressure Controlled GaN MBE Growth Using a Hollow Anode Nitrogen0 v4493 a

GaN films were grown on sapphire substrates at temperatures below 1000 K utilizing a Hollow Anode nitrogen ion source. A Ga flux limited growth rate of ~0.5 μm/h is demonstrated. Active utilization of strain and the assistance of a nitrogen partial pressure during buffer layer growth are found to be crucial issues that can improve the film quality. The best films exhibit a full width at half maximum of the x-ray rocking curves of 80 arcsec and 1.85 meV for the excitonic photoluminescence measured at 4 K. A Volmer-Weber three dimensional growth mode and the spontaneous formation of cubic GaN inclusions in the hexagonal matrix are observed in the investigated growth temperature range. It is argued that this growth mode contributes to a limitation of the carrier mobility in these films that did not exceed 120 cm2/Vs through a minimum canier concentration of ~1015 cm-3 was achieved.

1 aLeung, Michael, S.H.1 aKlockenbrink, Ralf1 aKisielowski, Christian, F.1 aFujii, Hiroaki1 aKrüger, Joachim1 aSubramanya, Sudhir, G.1 aAnders, André1 aLiliental-Weber, Zuzanna1 aRubin, Michael, D.1 aWeber, Eicke, R.1 aKrüger, Joachim uhttps://facades.lbl.gov/publications/pressure-controlled-gan-mbe-growth01836nas a2200169 4500008004100000050001500041245008800056210006900144260002700213520124400240100001701484700001901501700002301520700002401543700002301567856007601590 1996 eng d aLBNL-3963300aAnalysis of Durability in Lithium Nickel Oxide Electrochromic Materials and Devices0 aAnalysis of Durability in Lithium Nickel Oxide Electrochromic Ma aSan Diego, CAc10/19963 a

Thin films of lithium nickel oxide were deposited by sputtering and laser ablation from targets of pressed nickel oxide and lithium oxide powders. These films were assembled into electrochromic test devices with tungsten oxide as the opposite electrode and a polymer electrolyte. Analysis of the failure modes was carried out at several levels: The composition and structure of the films were examined before and after cycling using a variety of techniques, such as infrared spectroscopy, nuclear-reaction analysis, Rutherford backscattering spectrometry, x-ray diffraction and atomic force microscopy. Absorption of water vapor was found to be a major factor determining the cyclic stability of the films. A new technique is described for incorporating reference electrodes made from an electronically isolated corner into devices. This structure enabled identification of potential problems associated with a particular interface. Finally, some of the devices were disassembled and the components examined. For example, a small quantity of the polymer was extracted and studied by gas chromatography and mass spectroscopy. Small organic fragments were discovered which correspond to expected weak points in the polymer structures.

1 aWen, Shi-Jie1 aKerr, John, B.1 aRubin, Michael, D.1 aSlack, Jonathan, L.1 avon Rottkay, Klaus uhttps://facades.lbl.gov/publications/analysis-durability-lithium-nickel01697nas a2200205 4500008004100000245008500041210006900126300000800195490000800203520102000211100001901231700003101250700002101281700002501302700002301327700002301350700002101373700002101394856007601415 1996 eng d00aImpact of Growth Temperature, Pressure and Strain on the Morphology of GaN Films0 aImpact of Growth Temperature Pressure and Strain on the Morpholo a2270 v4493 a

GaN films grown on sapphire at different temperatures are investigated. A Volmer-Weber growth mode is observed at temperatures below 1000K that leads to thin films composed of oriented grains with finite size. Their size is temperature dependent and can actively be influenced by strain. Largest grains are observed in compressed films. It is argued that diffusing Ga ad-atoms dominate the observed effects with an activation energy of 2.3 ± 0.5 eV. Comparably large grain sizes are observed in films grown on off-axes sapphire substrates and on bulk GaN. This assures that the observed size limitation is a consequence of the 3D growth mode and not dependent on the choice of the substrate. In addition, the grain size and the surface roughness of the films depend on the nitrogen partial pressure in the molecular beam epitaxy (MBE) chamber,most likely due to collisions between the reactive species and the background gas molecules. This effect is utilized to grow improved nucleation layers on sapphire.

1 aFujii, Hiroaki1 aKisielowski, Christian, F.1 aKrüger, Joachim1 aLeung, Michael, S.H.1 aKlockenbrink, Ralf1 aRubin, Michael, D.1 aWeber, Eicke, R.1 aKrüger, Joachim uhttps://facades.lbl.gov/publications/impact-growth-temperature-pressure01797nas a2200145 4500008004100000050001500041245005700056210005700113260002700170520132200197100002301519700002301542700001901565856006701584 1996 eng d aLBNL-3959400aOptical Modeling of a Complete Electrochromic Device0 aOptical Modeling of a Complete Electrochromic Device aSan Diego, CAc10/19963 a

Optical indices have been determined for thin films of all materials needed to model a typical electrochromic device. Two electrochromic materials, tungsten oxide and lithium nickel oxide, are widely used in electrochromic devices. The optical indices of the underlying transparent conductors as well as a polymer electrolyte were also analyzed. The optical data was obtained using a combination of variable-angle spectroscopic ellipsometry and spectroradiometry. The data was then fit to appropriate models of structure and dispersion in order to extract the optical indices of the materials. First, the optical indices of the transparent conductive substrates were obtained and fixed in the model. The best models correspond well to independent physical measurements of film structure, such as atomic-force microscopy and surface profiling. Surface roughness, gradient composition and other types of inhomogeneity are common in both the transparent conductors and electrochromic, resulting in particularly complex models. The polymer has a homogeneous structure, but obtaining optically smooth surfaces was a problem. Complete sets of data were produced over the entire solar spectrum for a range of colored states of the films. Using the data for each layer, a realistic electrochromic device was simulated.

1 avon Rottkay, Klaus1 aRubin, Michael, D.1 aKerr, John, B. uhttps://facades.lbl.gov/publications/optical-modeling-complete01453nas a2200265 4500008004100000050001500041245003900056210003900095260001400134300000800148490000600156520070600162100003100868700002100899700002500920700002300945700001900968700001900987700002701006700001901033700002301052700002101075700002101096856007001117 1996 eng d aLBNL-3985300aOrigin of Strain in GaN Thin Films0 aOrigin of Strain in GaN Thin Films aSingapore a5130 v43 a

Photoluminescence measurements are used to determine the strain in GaN thin films grown by Molecular Beam Epitaxy. The strain which originates from growth on lattice mismatched substrates and from differences in thermal expansion coefficients is found to be greatly relaxed. Residual strains are shown to depend on the thickness of GaN buffer layers and the III/V flux ration during main layer growth. The results strongly suggest that the residual biaxial strain caused by the post-growth cooling can be modified by the incorporation of point defects during the main layer growth which introduce an additional hydrostatic strain field. The effect allows for strain engineering of GaN crystals.

1 aKisielowski, Christian, F.1 aKrüger, Joachim1 aLeung, Michael, S.H.1 aKlockenbrink, Ralf1 aFujii, Hiroaki1 aSuski, Tadeusz1 aSubramanya, Sudhir, G.1 aAger, Joel, W.1 aRubin, Michael, D.1 aWeber, Eicke, R.1 aKrüger, Joachim uhttps://facades.lbl.gov/publications/origin-strain-gan-thin-films01177nas a2200145 4500008004100000050001500041245011000056210006900166260003000235490001600265520062700281100002200908700002400930856007700954 1996 eng d aLBNL-3924800aSolar Heat Gain Coefficient of Complex Fenestrations with a Venetian Blind for Differing Slat Tilt Angles0 aSolar Heat Gain Coefficient of Complex Fenestrations with a Vene aPhiladelphia, PAc01/19970 v103, Part 13 a

Measured bidirectional transmittances and reflectances of a buff-colored venetian blind together with a layer calculation scheme developed in previous publications are utilized to produce directional-hemispherical properties for the venetian blind layer and solar heat gain coefficients for the blind in combination with clear double glazing. Results are presented for three blind slat tilt angles and for the blind mounted either interior to the double glazing or between the glass panes. Implications of the results for solar heat gain calculations are discussed in the context of sun positions for St. Louis, MO.

1 aKlems, Joseph, H.1 aWarner, Jeffrey, L. uhttps://facades.lbl.gov/publications/solar-heat-gain-coefficient-complex02402nas a2200265 4500008004100000245004700041210004700088260001200135300001600147490000700163520162000170100003101790700002101821700002001842700001901862700001901881700002001900700002901920700002301949700002101972700002501993700002202018700002102040856007502061 1996 eng d00aStrain Related Phenomena in GaN Thin Films0 aStrain Related Phenomena in GaN Thin Films c12/1996 a17745-177530 v543 a

Photoluminescence (PL), Raman spectroscopy, and x-ray diffraction are employed to demonstrate the co-existence of a biaxial and a hydrostatic strain that can be present in GaN thin films. The biaxial strain originates from growth on lattice-mismatched substrates and from post-growth cooling. An additional hydrostatic strain is shown to be introduced by the presence of point defects. A consistent description of the experimental results is derived within the limits of the linear and isotropic elastic theory using a Poisson ratio nu =0.23+/-0.06 and a bulk modulus B=200+/-20 GPa. These isotropic elastic constants help to judge the validity of published anisotropic elastic constants that vary greatly. Calibration constants for strain-induced shifts of the near-band-edge PL lines with respect to the E2 Raman mode are given for strain-free, biaxially strained, and hydrostatically contracted or expanded thin films. They allow us to extract differences between hydrostatic and biaxial stress components if present. In particular, we determine that a biaxial stress of one GPa would shift the near-band-edge PL lines by 27+/-2 meV and the E2 Raman mode by 4.2+/-0.3 cm-1 by use of the listed isotropic elastic constants. It is expected from the analyses that stoichiometric variations in the GaN thin films together with the design of specific buffer layers can be utilized to strain engineer the material to an extent that greatly exceeds the possibilities known from other semiconductor systems because of the largely different covalent radii of the Ga and the N atom.

1 aKisielowski, Christian, F.1 aKrüger, Joachim1 aRuvimov, Sergei1 aSuski, Tadeusz1 aAger, Joel, W.1 aJones, Erin, C.1 aLiliental-Weber, Zuzanna1 aRubin, Michael, D.1 aWeber, Eicke, R.1 aBremser, Michael, D.1 aDavis, Robert, F.1 aKrüger, Joachim uhttps://facades.lbl.gov/publications/strain-related-phenomena-gan-thin01286nas a2200133 4500008004100000050001400041245009700055210006900152490001600221520079900237100002201036700002001058856007401078 1995 eng d aLBL-3703800aCalorimetric Measurements of Inward-Flowing Fraction for Complex Glazing and Shading Systems0 aCalorimetric Measurements of InwardFlowing Fraction for Complex 0 v102, Part 13 a

This paper presents a calorimetric measurement of layer-specific inward-flowing fractions of absorbed solar energy for a number of geometric configurations common in fenestrations with shading. The inward-flowing fractions are found to be relatively insensitive to exterior conditions. Results for an interior venetian blind over double glazing agree with thermal model calculations in the literature, and are the first layer-specific verification of these calculations. It is argued that a data base of these inward-flowing fractions for a suitably broad class of geometries will make possible the determination of solar heat gain coefficient from non-calorimetric measurements of solar-optical properties of complex fenestration components, a procedure termed solar-thermal separation.

1 aKlems, Joseph, H.1 aKelley, Guy, O. uhttps://facades.lbl.gov/publications/calorimetric-measurements-inward01580nas a2200157 4500008004100000050001400041245008700055210006900142260002500211490001600236520102900252100002201281700002401303700002001327856007501347 1995 eng d aLBL-3703700aA Comparison Between Calculated and Measured SHGC For Complex Fenestration Systems0 aComparison Between Calculated and Measured SHGC For Complex Fene aAtlanta, GAc02/19960 v102, Part 13 a

Calorimetric measurements of the dynamic net heat flow through a complex fenestration system consisting of a buff venetian blind inside clear double glazing are used to derive the direction-dependent beam SHGC of the fenestration. These measurements are compared with calculations according to a proposed general method for deriving complex fenestration system SHGCs from bidirectional layer optical properties and generic calorimetric properties. Previously published optical measurements of the same venetian blind and generic inward-flowing fraction measurements are used in the calculation. The authors find satisfactory agreement between the SHGC measurements and the calculation.

Significant dependence on incident angle was found in the measured SHGCs. Profile angle was not found to be a useful variable in characterizing the system performance. The predicted SHGC was found to be inherently dependent on two angles, although only the incident angle variations were observable under the test conditions.

1 aKlems, Joseph, H.1 aWarner, Jeffrey, L.1 aKelley, Guy, O. uhttps://facades.lbl.gov/publications/comparison-between-calculated-and02822nas a2200217 4500008004100000024001100041245005700052210005700109260002700166520217700193653002802370653002002398100001902418700001902437700002302456700001602479700002102495700001802516700001902534856005102553 1995 eng d aUC-42600aFormation of Metal Oxides by Cathodic Arc Deposition0 aFormation of Metal Oxides by Cathodic Arc Deposition aSan Diego, CAc04/19953 a

Metal oxide thin films are of interest for a number of applications. Cathodic arc deposition, which is an established and industrially applied technique for the formation of nitrides (e.g. TIN), can also be used for metal oxide thin film formation. A cathodic arc plasma source with the desired cathode material is operated in an oxygen atmosphere of appropriate pressure, and metal oxides of various stoichiometric composition can be formed on different substrates. We report here on a series of experiments on metal oxide formation by cathodic arc deposition for different applications. Black copper oxide has been deposited on accelerator components to increase the radiative heat transfer between the parts. Various metal oxides such as tungsten oxide, niobium oxide, nickel oxide and vanadium oxide have been deposited on ITO glass to form electrochromic films for window applications. Tantalum oxide films are of interest for replacing polymer electrolytes. Optical waveguide structures can be formed by refractive index variation using oxide multilayers. We have synthesized multilayers of Al2O3/Y2O3/Al2O3/Si as possible basic structures for passive optoelectronic integrated circuits, and Al2-xErxO3 thin films with a variable Er concentration which is a potential component layer for the production of active optoelectronic integrated devices such as amplifiers or lasers at a wavelength of 1.53 pm. Aluminum and chromium oxide films have been deposited on a number of substrates to impart improved corrosion resistance at high temperature. Titanium sub-oxides which are electrically conductive and corrosion resistant and stable in a number of aggressive environments have been deposited on various substrates. These sub-oxides are of great interest for use in electrochemical cells. Common features of all these depositions are the high deposition rate typical for cathodic arc deposition, the good adhesion of the films due to the high metal ion energy, and the advantage of an environmentally clean method in comparison to wet-chemical oxide formation techniques.

10aCathodic arc deposition10aOxide formation1 aAnders, Simone1 aAnders, André1 aRubin, Michael, D.1 aWang, Zhien1 aRaoux, Sebastien1 aKong, Fanping1 aBrown, Ian, G. uhttp://dx.doi.org/10.1016/0257-8972(95)02508-100835nas a2200145 4500008004100000050001400041245004700055210004700102260003400149520037100183100002200554700002100576700002000597856007200617 1995 eng d aLBL-3774700aMeasured Performance of Selective Glazings0 aMeasured Performance of Selective Glazings aClearwater Beach, FLc12/19953 a

Measurements of the net heat flow through four selective glazings in comparison with clear double glazing under late summer outdoor conditions are presented. The solar heat gain coefficient (SHGC) for each glazing is extracted from the data and shown to be angle-dependent. Good agreement is found between measured properties and calculations with WINDOW 4.1.

1 aKlems, Joseph, H.1 aYazdanian, Mehry1 aKelley, Guy, O. uhttps://facades.lbl.gov/publications/measured-performance-selective01775nas a2200133 4500008004100000050001400041245007900055210006900134490001600203520130100219100002201520700002401542856007501566 1995 eng d aLBL-3624300aMeasurement of Bidirectional Optical Properties of Complex Shading Devices0 aMeasurement of Bidirectional Optical Properties of Complex Shadi0 v101, Part 13 a

A new method of predicting the solar heat gain through complex fenestration systems involving nonspecular layers such as shades or blinds has been examined in a project jointly sponsored by ASHRAE and DOE. In this method, a scanning radiometer is used to measure the bidirectional radiative transmittance and reflectance of each layer of a fenestration system. The properties of systems containing these layers are then built up computationally from the measured layer properties using a transmission/multiple-reflection calculation. The calculation produces the total directional-hemispherical transmittance of the fenestration system and the layer-by-layer absorptances. These properties are in turn combined with layer-specific measurements of the inward-flowing fractions of absorbed solar energy to produce the overall solar heat gain coefficient.

This paper describes the method of measuring the spatially averaged bidirectional optical properties using an automated, large-sample gonio-radiometer/photometer, termed a Scanning Radiometer. Property measurements are presented for one of the most optically complex systems in common use, a venetian blind. These measurements will form the basis for optical system calculations used to test the method of determining performance.

1 aKlems, Joseph, H.1 aWarner, Jeffrey, L. uhttps://facades.lbl.gov/publications/measurement-bidirectional-optical02537nas a2200181 4500008004100000050001400041245010200055210006900157260003100226520187100257100002102128700002702149700002802176700002202204700002502226700002902251856007502280 1994 eng d aLBL-3573200aA Comprehensive Approach to Integrated Envelope and Lighting Systems for New Commercial Buildings0 aComprehensive Approach to Integrated Envelope and Lighting Syste aPacific Grove, CAc09/19943 a

We define a comprehensive approach to integrated envelope and lighting systems design as one that balances energy efficiency with anequal regard to the resultant environmental quality. By integrating envelope components (glazing, shading, and daylighting), lighting components (fixtures and controls) and building HVAC/ energy management control systems, we create building systems that have the potential to achieve significant decreases in electricity consumption and peak demand while satisfying occupant physiological and psychological concerns.

This paper presents results on the development, implementation, and demonstration of two specific integrated envelope and lighting systems:

  1. A system emphasizing dynamicsenvelope components and responsive electric lighting systems, that offer the potential to achieve energy efficiency goals and a near optimum comfort environment throughout the year by adapting to meteorological conditions and occupant preferences in real time, and
  2. perimeter daylighting systems that increase the depth of daylight penetration from sidelight windows and improves visual comfort with the use of a small inlet aperture.

The energy performance of the systems was estimated using the DOE-2 building energy simulation program. Field tests with reduced scale models were conducted to determine daylighting and thermal performance in real time under actual weather conditions. Demonstrations of these integrated systems are being planned or are in progress in collaboration with utility programs to resolve real-world implementation issues under complex site, building, and cost constraints. Results indicate that integrated systems offer solutions that not only achieve significant peak demand reductions but also realize consistent energy savings with added occupant comfort and satisfaction.

1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E.1 aRubinstein, Francis, M.1 aKlems, Joseph, H.1 aBeltran, Liliana, O.1 aDiBartolomeo, Dennis, L. uhttps://facades.lbl.gov/publications/comprehensive-approach-integrated01301nas a2200133 4500008004100000050001400041245009400055210006900149490001600218520081200234100002101046700002201067856007801089 1993 eng d aLBL-3471700aMeasurement of the Exterior Convective Film Coefficient for Windows in Low-Rise Buildings0 aMeasurement of the Exterior Convective Film Coefficient for Wind0 v100, Part 13 a

The MoWiTT field facility is used to measure the convective film coefficient over the exterior surface of a window. The MoWiTT-measured data is compared to some commonly-used experimental and theoretical models. The comparison shows that the MoWiTT data disagrees with the previously used models such as the ASHRAE/DOE-2 model. The reasons for these disagreements are discussed. An experimental model, based on the MoWiTT data, is presented to correlate the film coefficient with the difference in temperatures of the exterior glass surface and the ambient, in the natural convection region, and with the site wind speed, in the forced convection region. The wind speed is considered both in windward and leeward hemispheres. The validity of the MoWiTT model for low-rise buildings is then discussed.

1 aYazdanian, Mehry1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/measurement-exterior-convective-film01572nas a2200121 4500008004100000024001100041245014100052210006900193490000800262520108200270100002201352856007601374 1993 eng d aDA-32100aA New Method for Predicting the Solar Heat Gain of Complex Fenestration Systems II. Detailed Description of the Matrix Layer Calculation0 aNew Method for Predicting the Solar Heat Gain of Complex Fenestr0 v1003 a

A new method of predicting the solar heat gain through complex fenestration systems involving nonspecular layers such as shades or blinds has been examined in a project jointly sponsored by ASHRAE and DOE. In this method, a scanning radiometer is used to measure the bi-directional radiative transmittance and reflectance of each layer of a fenestration system. The properties of systems containing these layers are then built up computationally from the measured layer properties using a transmission/multiple-reflection calculation. The calculation produces the total directional-hemispherical transmittance of the fenestration system and the layer-by-layer absorptances. These properties are in turn combined with layer-specific measurements of the inward-flowing fractions of absorbed solar energy to produce the overall solar heat gain coefficient.

A preceding paper outlined the method and provided the physical derivation of the calculation. In this second of a series of related papers the detailed development of the matrix layer calculation is presented.

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/new-method-predicting-solar-heat-101903nas a2200133 4500008004100000050001400041245014300055210006900198260002800267490001600295520136000311100002201671856007601693 1993 eng d aLBL-3471500aA New Method for Predicting the Solar Heat Gain of Complex Fenestration Systems I. Overview and Derivation of the Matrix Layer Calculation0 aNew Method for Predicting the Solar Heat Gain of Complex Fenestr aNew Orleans LAc01/19940 v100, Part 13 a

A new method of predicting the solar heat gain through complex fenestration systems involving nonspecular layers such as shades or blinds has been examined in a project jointly sponsored by ASHRAE and DOE. In this method, a scanning radiometer is used to measure the bidirectional radiative transmittance and reflectance of each layer of a fenestration system. The properties of systems containing these layers are then built up computationally from the measured layer properties using a transmission/multiple-reflection calculation. The calculation produces the total directional-hemispherical transmittance of the fenestration system and the layer-by-layer absorptances. These properties are in turn combined with layer-specific measurements of the inward-flowing fractions of absorbed solar energy to produce the overall solar heat gain coefficient. In this first in a series of related papers describing the project, the assumptions and limitations of the calculation method are described and the derivation of the matrix calculation technique from the initial integral equations is presented.

In this first in a series of related papers describing the project, the assumptions and limitations of the calculation method are described and the derivation of the matrix calculation technique from the initial integral equations is presented.

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/new-method-predicting-solar-heat-001773nas a2200181 4500008004100000245006900041210006800110260001200178490001500190520118600205100002501391700002201416700002001438700002001458700002301478700002001501856007001521 1993 eng d00aPhase I Results of the NFRC U-Value Procedure Validation Project0 aPhase I Results of the NFRC UValue Procedure Validation Project c08/19930 v100, Pt. 13 a

The NFRC U-Value Procedure Validation Project was undertaken by a collaborative group of industry, public utility, trade associations, and government researchers in order to validate the testing and calculational methods of the NFRC 100-91: Procedure for Determining Fenestration Product Thermal Properties (Currently Limited to U-Values). This paper summarizes the validation projects goals and test methodology, the results of the data analysis, and the recommendations following completion of Phase I of the project. Simulations performed according to NFRC 100-91 are shown to agree with each other, to within the NFRC tolerance, in 100% of the cases. Window test results with perpendicular wind performed according to NFRC 100-91 are shown to agree with each other, to within the NFRC tolerance, in 84% of the cases. Simulations and perpendicular wind window test results are shown to agree with each other, to within the NFRC tolerance, in 80% of the cases. Testing of skylights was shown to be problematic under the procedure as written at the time. Agreement between tests and simulations will improve as a result of a strong NFRC education and accreditation program.

1 aArasteh, Dariush, K.1 aBeck, Fredric, A.1 aStone, Nehemiah1 aDuPont, William1 aMathis, Christophe1 aKoenig, Michael uhttps://facades.lbl.gov/publications/phase-i-results-nfrc-u-value01559nas a2200097 4500008004100000245006100041210006000102520119800162100002201360856007901382 1992 eng d00aNet Energy Performance Measurements on Two Low-E Windows0 aNet Energy Performance Measurements on Two LowE Windows3 a

Experimental studies using the Mobile Window Thermal Test (MoWiTT) Facility were undertaken to compare the performance of low-E windows manufactured with two different technologies, sputter-coated (soft-coat) and an improved pyrolytic chemical vapor deposition (hard-coat). The two technologies produce coatings with different emissivities and solar absorptions. The tests showed that from the standpoint of winter average daily performance, the higher solar transmission of the pyrolytic coatings tends to offset their higher emissivity, making the average performance of windows with the two coatings more similar than one would predict on the basis of either property alone. The tradeoff between the two window types is both orientation and climate dependent. Differences between the two windows were within the small experimental uncertainty of the measurement for all orientations except south, where the pyrolytic coating produced a larger net heat gain. Summer tests in a west-facing orientation showed that both windows produced large solar heat gains if unshaded, and that shading with an interior white venetian blind was not a very effective way of reducing these heat gains.

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/net-energy-performance-measurements-001745nas a2200133 4500008004100000050001400041245008400055210006900139260003400208520124400242100002201486700002401508856007901532 1992 eng d aLBL-3219800aA New Method for Predicting the Solar Heat Gain of Complex Fenestration Systems0 aNew Method for Predicting the Solar Heat Gain of Complex Fenestr aClearwater Beach, FLc12/19923 a

A new method of predicting the solar heat gain through complex fenestration systems involving nonspecular layers such as shades or blinds has been examined in a project jointly sponsored by ASHRAE and DOE. In this method, a scanning radiometer is used to measure the bi-directional radiative transmittance and reflectance of each layer of a fenestration system. The properties of systems containing these layers are then built up computationally from the measured layer properties using a transmission/multiple-reflection calculation. The calculation produces the total directional-hemispherical transmittance of the fenestration system and the layer-by-layer absorptances. These properties are in turn combined with layer-specific measurements of the inward-flowing fractions of absorbed solar energy to produce the overall solar heat gain coefficient.

The method has been applied to one of the most optically complex systems in common use, a venetian blind in combination with multiple glazings. A comparison between the scanner-based calculation method and direct system calorimetric measurements made on the LBL MoWiTT facility showed good agreement, and is a significant validation of the method accuracy and feasibility.

1 aKlems, Joseph, H.1 aWarner, Jeffrey, L. uhttps://facades.lbl.gov/publications/new-method-predicting-solar-heat-gain