01199nas a2200253 4500008003900000245007500039210006900114260001200183300001400195490000600209520041200215653002400627653002100651653001600672653002800688653002000716100002200736700002500758700001800783700002600801700001800827700002400845856007600869 2013 d00aNear-Infrared Spectrally Selective Plasmonic Electrochromic Thin Films0 aNearInfrared Spectrally Selective Plasmonic Electrochromic Thin  c03/2013 a215 - 2200 v13 a

A plasmonic electrochromic effect in which electrochemical doping reversibly modulates near-infrared surface plasmon absorption of aluminium-doped zinc oxide and tin-doped indium oxide nanocrystals is reported. Optical performance, switching kinetics, and cycling durability point to high-performance NIR selective plasmonic electrochromic coatings based on earth-abundant materials.

10aaluminum zinc oxide10aindium tin oxide10ananocrystal10aspectroelectrochemistry10asurface plasmon1 aGarcia, Guillermo1 aBuonsanti, Raffaella1 aLlordes, Anna1 aRunnerstrom, Evan, L.1 aBergerud, Amy1 aMilliron, Delia, J. uhttps://facades.lbl.gov/publications/near-infrared-spectrally-selective01789nas a2200217 4500008003900000245015800039210006900197260006500266520094400331100002101275700002401296700002201320700001901342700002201361700002401383700002101407700002701428700002301455700001601478856007701494 2013 d00aA Post-Occupancy Monitored Evaluation of the Dimmable Lighting, Automated Shading, and Underfloor Air Distribution System in The New York Times Building0 aPostOccupancy Monitored Evaluation of the Dimmable Lighting Auto aBerkeley, CAbLawrence Berkeley National Laboratoryc01/20133 a

With aggressive goals to reduce national energy use and carbon emissions, the US Department of Energy will be looking to exemplary buildings that have already invested in new approaches to achieving the energy performance goals now needed at a national level. The New York Times Building, in New York, New York, incorporates a number of innovative technologies, systems and processes and could become a model for widespread replication in new and existing buildings. Post-occupancy data are invaluable in establishing confidence in innovation. A year-long monitored study was conducted to verify energy performance, assess occupant comfort and satisfaction with the indoor environment, and evaluate impacts on maintenance and operations. Lessons learned were derived from the analysis; these lessons could help identify and shape policy, financial, or supporting strategies to accelerate diffusion in the commercial building market.

1 aLee, Eleanor, S.1 aFernandes, Luis, L.1 aCoffey, Brian, E.1 aMcNeil, Andrew1 aClear, Robert, D.1 aWebster, Thomas, L.1 aBauman, Fred, S.1 aDickerhoff, Darryl, J.1 aHeinzerling, David1 aHoyt, Tyler uhttps://facades.lbl.gov/publications/post-occupancy-monitored-evaluation01318nas 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/2gm7r78301680nas 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-and01433nas a2200289 4500008003900000022001400039245009300053210006900146260001200215300001600227490000700243520053600250653001100786653002100797653001600818653002800834653002000862100002200882700002500904700002600929700002800955700001800983700001901001700002701020700002401047856007201071 2011 d a1530-698400aDynamically Modulating the Surface Plasmon Resonance of Doped Semiconductor Nanocrystals0 aDynamically Modulating the Surface Plasmon Resonance of Doped Se c10/2011 a4415 - 44200 v113 a

Localized surface plasmon absorption features arise at high doping levels in semiconductor nanocrystals, appearing in the near-infrared range. Here we show that the surface plasmons of tin-doped indium oxide nanocrystal films can be dynamically and reversibly tuned by postsynthetic electrochemical modulation of the electron concentration. Without ion intercalation and the associated material degradation, we induce a > 1200 nm shift in the plasmon wavelength and a factor of nearly three change in the carrier density.

10adoping10aindium tin oxide10ananocrystal10aspectroelectrochemistry10asurface plasmon1 aGarcia, Guillermo1 aBuonsanti, Raffaella1 aRunnerstrom, Evan, L.1 aMendelsberg, Rueben, J.1 aLlordes, Anna1 aAnders, André1 aRichardson, Thomas, J.1 aMilliron, Delia, J. uhttps://facades.lbl.gov/publications/dynamically-modulating-surface00712nas a2200157 4500008003900000022001400039245004300053210004100096260001200137300001600149490000700165520027300172100001900445700001600464856007400480 2011 d a0093-381300aA Plasma Lens for Magnetron Sputtering0 aPlasma Lens for Magnetron Sputtering c11/2011 a2528 - 25290 v393 a

A plasma lens, consisting of a solenoid and potential-defining ring electrodes, has been placed between a magnetron and substrates to be coated. Photography reveals qualitative information on excitation, ionization, and the transport of plasma to the substrate.

1 aAnders, André1 aBrown, Jeff uhttps://facades.lbl.gov/publications/plasma-lens-magnetron-sputtering01581nas a2200181 4500008004100000050001500041245011400056210006900170520095200239100001901191700002201210700001701232700002201249700002001271700002001291700001601311856007201327 2009 eng d aLBNL-1881E00aHigh quality ZnO:Al transparent conducting oxide films synthesized by pulsed filtered cathodic arc deposition0 aHigh quality ZnOAl transparent conducting oxide films synthesize3 a

Aluminum-doped zinc oxide, ZnO:Al or AZO, is a well-known n-type transparent conducting oxide with great potential in a number of applications currently dominated by indium tin oxide (ITO). In this study, the optical and electrical properties of AZO thin films deposited on glass and silicon by pulsed filtered cathodic arc deposition are systematically studied. In contrast to magnetron sputtering, this technique does not produce energetic negative ions, and therefore ion damage can be minimized. The quality of the AZO films strongly depends on the growth temperature while only marginal improvements are obtained with post-deposition annealing. The best films, grown at a temperature of about 200°C, have resistivities in the low to mid 10-4Ω cm range with a transmittance better than 85% in the visible part of the spectrum. It is remarkable that relatively good films of small thickness (60 nm) can be fabricated using this method.

1 aAnders, André1 aLim, Sunnie, H.N.1 aYu, Kin, Man1 aAndersson, Joakim1 aRosén, Johanna1 aMcFarland, Mike1 aBrown, Jeff uhttps://facades.lbl.gov/publications/high-quality-znoal-transparent01696nas 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-loss01753nas a2200145 4500008004100000050001500041245012900056210006900185300001200254490000800266520121600274100002301490700002001513856007401533 2007 eng d aLBNL-6182600aObtaining the Bidirectional Transfer Distribution Function of Isotropically Scattering Materials Using an Integrating Sphere0 aObtaining the Bidirectional Transfer Distribution Function of Is a228-2360 v2773 a

This paper demonstrates a method to determine the bidirectional transfer distribution function (BTDF) using an integrating sphere. Information about the sample's angle dependent scattering is obtained by making transmittance measurements with the sample at different distances from the integrating sphere. Knowledge about the illuminated area of the sample and the geometry of the sphere port in combination with the measured data combines to an system of equations that includes the angle dependent transmittance. The resulting system of equations is an ill-posed problem which rarely gives a physical solution. A solvable system is obtained by using Tikhonov regularization on the ill-posed problem. The solution to this system can then be used to obtain the BTDF. Four bulk-scattering samples were characterised using both two goniophotometers and the described method to verify the validity of the new method. The agreement shown is great for the more diffuse samples. The solution to the low-scattering samples contains unphysical oscillations, but still gives the correct shape of the solution. The origin of the oscillations and why they are more prominent in low-scattering samples are discussed.

1 aJonsson, Jacob, C.1 aBranden, Henrik uhttps://facades.lbl.gov/publications/obtaining-bidirectional-transfer01066nas 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-films01808nas 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-state01261nas a2200145 4500008004100000245009600041210006900137300001400206490000700220520078700227100001801014700002401032700001901056856004001075 2003 eng d00aCoalescence of Nanometer Silver Islands on Oxides Grown by Filtered Cathodic Arc Deposition0 aCoalescence of Nanometer Silver Islands on Oxides Grown by Filte a1634-16360 v823 a

Ultrathin silver films have been deposited on glass and oxide-coated glass using filtered cathodic arc deposition and, for comparison, magnetron sputtering. The energetic differences between these deposition methods lead to initially different film properties. Silver films made by cathodic arc deposition show an earlier onset of island coalescence, indicating a lower aspect ratio than islands produced by evaporation and sputtering. However, the as-deposited films are thermodynamically unstable, exhibiting changes on a timescale of minutes. While films of islands tend to increase their sheet resistance with time, the sheet resistance of contiguous films shows a decrease. Both effects can be explained by silver mobility driven to minimize film and interfacial energy.

1 aByon, Eungsun1 aOates, Thomas, W.H.1 aAnders, André uhttp://dx.doi.org/10.1063/1.155895502094nas a2200133 4500008004100000050001500041245010000056210006900156260002300225520159700248100001801845700001901863856007801882 2003 eng d aLBNL-5156800aEffect of Underlayer on Coalescence of Silver Islands Grown by Filtered Cathodic Arc Deposition0 aEffect of Underlayer on Coalescence of Silver Islands Grown by F aSan Diegoc05/20033 a

Ultrathin silver films that are not continuous show relatively high absorption in the visible and low reflection in the infrared. For low-emissivity application on window glass, coalescence of silver islands is crucial for obtaining the desired optical properties of the coating, namely high transparence in the visible and high reflectivity in the infrared. It is well known that the energy of ions arriving at the substrate and the type of underlayer affect nucleation and growth of silver islands. There are a number of studies on nucleation and growth, but little is known about coalescence of silver islands synthesized by more energetic condensation, e.g. filtered cathodic vacuum arc (FCVA). In this work, the effect of underlayer on nucleation and growth of silver films deposited by FCVA was investigated by transmission electron microscopy (TEM) and atomic force microscopy (AFM). The results arescompared with data obtained by magnetron sputtering.

From the results, plane and titanium-oxide-coated glass requires more material to achieve the same value of resistance than for the zinc oxide coated glass. It is related with the energy of interaction between the surface and the silver atom. Silver films made by cathodic arc deposition show an earlier onset of island coalescence and formation of short links. It was found that silver islands in energetic deposition exhibit a reduced aspect ratio when compared to evaporation and sputtering. Nb underlayer affects nucleation and growth of coalescence of silver only in the case of few monolayer of Nb was introduced.

1 aByon, Eungsun1 aAnders, André uhttps://facades.lbl.gov/publications/effect-underlayer-coalescence-silver02700nas a2200217 4500008004100000050001500041245009700056210006900153260003100222520195900253100002102212700002702233700001902260700002202279700002002301700002302321700002302344700001902367700002302386856007302409 2002 eng d aLBNL-5085500aActive Load Management with Advanced Window Wall Systems: Research and Industry Perspectives0 aActive Load Management with Advanced Window Wall Systems Researc aPacific Grove, CAc08/20023 a

Advanced window wall systems have the potential to provide demand response by reducing peak electric loads by 20-30% in many commercial buildings through the active control of motorized shading systems, switchable window coatings, operable windows, and ventilated double-skin facade systems. These window strategies involve balancing daylighting and solar heat gains, heat rejection through ventilation, and night-time natural ventilation to achieve space-conditioning and lighting energy use reductions without the negative impacts on occupants associated with other demand responsive (DR) strategies.

This paper explores conceptually how advanced window systems fit into the context of active load management programs, which cause customers to directly experience the time-varying costs of their consumption decisions. Technological options are suggested. We present pragmatic criteria that building owners use to determine whether to deploy such strategies. A utility's perspective is given. Industry also provides their perspectives on where the technology is today and what needs to happen to implement such strategies more broadly in the US.

While there is significant potential for these advanced window concepts, widespread deployment is unlikely to occur with business-as-usual practice. Technologically, integrated window-lighting-HVAC products are underdeveloped. Implementation is hindered by fragmented labor practices, non-standard communication protocols, and lack of technical expertise. Design tools and information products that quantify energy performance, occupant impacts, reliability, and other pragmatic concerns are not available. Interest within the building industry in sustainability, energy-efficiency, and increased occupant amenity, comfort, and productivity will be the driving factors for these advanced facades in the near term — at least until the dust settles on the deregulated electricity market.

1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E.1 aLevi, Mark, S.1 aBlanc, Steven, L.1 aMcConahey, Erin1 aMcClintock, Maurya1 aHakkarainen, Pekka1 aSbar, Neil, L.1 aMyser, Michael, P. uhttps://facades.lbl.gov/publications/active-load-management-advanced01602nas a2200145 4500008004100000050001500041245008200056210006900138300001400207490000700221520112200228100001801350700001901368856006901387 2002 eng d aLBNL-5179000aBias and Self-Bias of Magnetic Macroparticle Filters for Cathodic Arc Plasmas0 aBias and SelfBias of Magnetic Macroparticle Filters for Cathodic a8890-88970 v933 a

Curved magnetic filters are often used for the removal of macroparticles from cathodic arc plasmas. This study addresses the need to further reduce losses and improving plasma throughput. The central figure of merit is the system coefficient κ defined as a filtered ion current normalized by the plasma-producing arc current. The coefficient κ is investigated as a function of continuous and pulsed magnetic field operation, magnetic field strength, external electric bias, and arc amplitude. It increases with positive filter bias but saturates at about 15 V for relatively low magnetic field (~10 mT), whereas stronger magnetic fields lead to higher κ with saturation at about 25 V. Further increase of positive bias reduces κ. These findings are true for both pulsed and continuous filters. Bias of pulsed filters has been realized using the voltage drop across a self-bias resistor, eliminating the need for a separate bias circuit. Almost 100 A of filtered copper ions have been obtained in pulsed mode, corresponding to κ ≈ 0.04. The results are interpreted by a simplified potential trough model.

1 aByon, Eungsun1 aAnders, André uhttps://facades.lbl.gov/publications/bias-and-self-bias-magnetic02215nas a2200121 4500008004100000245007700041210006900118260001200187520177800199100001601977700002501993856007502018 2002 eng d00aAn Evaluation of Alternative Qualifying Criteria for Energy Star Windows0 aEvaluation of Alternative Qualifying Criteria for Energy Star Wi c05/20023 a

Energy Star is a voluntaly partnership between the U.S. Department of Energy (DOE), the U.S. Environmental Protection Agency (EPA), and industry. Energy Star, at both DOE andsEPA, is based on legislative mandates to implement voluntary, non-regulatory programs to promote products that are substantially more efficient than required by Federal standards (the DOE Energy Star program originated with Section 127 of the Energy Policy Act of 1992 (EPACT), and the EPA Energy Star program originated with Section 103 of the CleansAir Act amendments of 1990). The base criteria under EPACT requires DOE to establish voluntary energy efficiency product programs that serve to increase the technical energy performance potential of products, are cost-effective for the consumer, save energy and thus reduce green house gas emissions. Criteria used by EPA under the Clean Air Act are similar but reflect a greater emphasis on reducing green house gas emissions.

The primary objective of the partnership is to expand the market for energy-efficient products. EPA and DOE use the Energy Star label to recognize and promlote the most energy-efficient subset of the market. The label is a simple mechanism that allows consumers to easily identify the most energy-efficient products in the marketplace. In developing specifications for the Energy Star label, EPA and DOE consider several key factors, including:

1 aBarbour, Ed1 aArasteh, Dariush, K. uhttps://facades.lbl.gov/publications/evaluation-alternative-qualifying02180nas 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-building02296nas 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-laboratory02126nas a2200169 4500008004100000050001500041245006600056210006600122260003400188520154400222100002101766700002501787700002101812700002301833700002701856856007301883 1998 eng d aLBNL-4169400aEnergy and Daylight Performance of Angular Selective Glazings0 aEnergy and Daylight Performance of Angular Selective Glazings aClearwater Beach, FLc12/19983 a

This paper presents the results of a study investigating the energy and daylight performance of anisotropic angular selective glazings. The DOE-2.1E energy simulation program was used to determine the annual cooling, lighting and total electricity use, and peak electric demand. RADIANCE, a lighting simulation program, was used to determine daylight illuminance levels and distribution. We simulated a prototypical commercial office building module located in Blythe, California. We chose three hypothetical conventional windows for comparison: a single-pane tinted window, a double-pane low-E window, and a double-pane spectrally selective window. Daylighting controls were used. No interior shades were modeled in order to isolate the energy effects of the angular selective glazing. Our results show that the energy performance of the prototype angular selective windows is about the same as conventional windows for a 9.14 m (30 ft) deep south-facing perimeter zone with a large-area window in the hot, sunny climate of Blythe. It is theoretically possible to tune the angular selectivity of the glazing to achieve annual cooling energy reductions of 18%, total electricity use reductions of 15%, and peak electric demand reductions of 11% when compared to a conventional glazing with the same solar-optical properties at normal incidence. Angular selective glazings can provide more uniformly distributed daylight, particularly in the area next to the window, which will result in a more visually comfortable work environment.

1 aSullivan, Robert1 aBeltran, Liliana, O.1 aLee, Eleanor, S.1 aRubin, Michael, D.1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/energy-and-daylight-performance01627nas a2200157 4500008004100000245007200041210006900113260001800182300001100200490000700211520110000218100002501318700002101343700002701364856007801391 1997 eng d00aAdvanced Optical Daylighting Systems: Light Shelves and Light Pipes0 aAdvanced Optical Daylighting Systems Light Shelves and Light Pip aCleveland, OH a91-1060 v263 a

We present two perimeter daylighting systems that passively redirect beam sunlight further from the window wall using special optical films, an optimized geometry, and a small glazing aperture. The objectives of these systems are (1) to increase daylight illuminance levels at 4.6-9.1 m (15-30 ft) from the window aperture with minimum solar heat gains and (2) to improve the uniformity of the daylighting luminance gradient across the room under variable solar conditions throughout the year. The designs were developed through a series of computer-assisted ray-tracing studies, laser visualization techniques, and photometric measurements and observations using physical scale models. Bi-directional illuminance measurements in combination with analytical routines were then used to simulate daylight performance for any solar position, and were incorporated into the DOE-2.1E building energy analysis computer program to evaluate energy savings. Results show increased daylight levels and an improved luminance gradient throughout the year compared to conventional daylighting systems.

1 aBeltran, Liliana, O.1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/advanced-optical-daylighting-systems01722nas a2200169 4500008004100000245006100041210006100102260003100163490001600194520115400210100002501364700002901389700002401418700001601442700002201458856007201480 1997 eng d00aGuidelines for Modeling Projecting Fenestration Products0 aGuidelines for Modeling Projecting Fenestration Products aSan Francisco, CAc01/19980 v104, Part 13 a

Heat transfer patterns in projecting fenestration products (greenhouse windows, skylights, etc.) are different than those with typical planar window products. The projecting surfaces often radiate to each other, thereby invalidating the commonly used assumption that fenestration product interior surfaces radiate to a uniform room air temperature. The convective portion of the surface heat transfer coefficient is also significantly different from the one used with planar geometries, and is even more dependent on geometry and location. Projecting fenestration product profiles must therefore be modeled in their entirety. This paper presents the results of complete cross section, variable film-coefficient, 2-D heat transfer modeling of two greenhouse windows using the next generation of window specific heat transfer modeling tools. The use of variable film-coefficient models is shown to increase the accuracy with which simulation tools can compute U-factors. Simulated U-factors are also determined using conventional constant film coefficient algorithms. The results from both sets of simulations are compared with measured values.

1 aArasteh, Dariush, K.1 aFinlayson, Elizabeth, U.1 aCurcija, Dragan, C.1 aBaker, Jeff1 aHuizenga, Charlie uhttps://facades.lbl.gov/publications/guidelines-modeling-projecting01361nas a2200145 4500008004100000050001400041245009700055210006900152260003100221520081700252100002101069700002501090700002701115856007301142 1996 eng d aLBL-3813100aDemonstration of a Light-Redirecting Skylight System at the Palm Springs Chamber of Commerce0 aDemonstration of a LightRedirecting Skylight System at the Palm  aPacific Grove, CAc08/19963 a

As part of a demonstration project to provide a comprehensive energy upgrade to a 294 m2 (3168 ft2) commercial building, an advanced skylight design was developed using optical light control materials and geometry to provide daylight to two adjoining offices. The skylight system was developed using outdoor physical model tests and simulation tools Limited on-site measurements and occupant polls were conducted. Market issues were addressed. The skylight systems were found to improve lighting quality and to control excessive daylight illuminance levels compared to a conventional diffusing bubble skylight. Daylighting principles developed in earlier work for vertical glazing systems (light shelves and light pipes) were shown to be applicable in skylight designs at full-scale.

1 aLee, Eleanor, S.1 aBeltran, Liliana, O.1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/demonstration-light-redirecting02188nas a2200169 4500008004100000024001200041245007000053210006900123260002900192490001600221520160700237100002101844700002201865700002501887700002701912856007901939 1996 eng d aUC-160000aEnergy Performance of Evacuated Glazings in Residential Buildings0 aEnergy Performance of Evacuated Glazings in Residential Building aSan Antonio, TXc06/19960 v102, Part 23 a

This paper presents the results of a study investigating the energy performance of evacuated glazings or glazings which maintain a vacuum between two panes of glass. Their performance is measured by comparing results to prototype highly insulated superwindows as well as a more conventional insulating glass unit with a low-E coating and argon gas fill. We used the DOE-2.1E energy analysis simulation program to analyze the annual and hourly heating energy use due to the windows of a prototypical single-story house located in Madison, Wisconsin. Cooling energy performance was also investigated. Our results show that for highly insulating windows, the solar heat gain coefficient is as important as the windows U-factor in determining heating performance for window orientations facing west-south-east. For other orientations in which there is not much direct solar radiation, the windows U-factor primarily governs performance. The vacuum glazings had lower heating requirements than the superwindows for most window orientations. The conventional low-E window outperformed the superwindows for southwest-south-southeast orientations. These performance differences are directly related to the solar heat gain coefficients of the various windows analyzed. The cooling performance of the windows was inversely related to the heating performance. The low solar heat gain coefficients of the superwindows resulted in the best cooling performance. However, we were able to mitigate the cooling differences of the windows by using an interior shading device that reduced the amount of solar gain.

1 aSullivan, Robert1 aBeck, Fredric, A.1 aArasteh, Dariush, K.1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/energy-performance-evacuated-glazings02402nas 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-thin03749nas a2200193 4500008004100000245010100041210006900142260003400211520306200245100002903307700002503336700002303361700001803384700002103402700002203423700002403445700001603469856007003485 1995 eng d00aAdvances in Thermal and Optical Simulations of Fenestration Systems: The Development of WINDOW 50 aAdvances in Thermal and Optical Simulations of Fenestration Syst aClearwater Beach, FLc12/19953 a

WINDOW is a personal-computer-based computer program used by manufacturers, researchers, and consumers to evaluate the thermal performance properties (U-factors, solar heat gain and shading coefficients, and visible transmittances) of complete windows and other fenestration systems. While WINDOW is used by thousands of users in the United States and internationally and is at the foundation of the National Fenestration Rating Council's U-factor and solar heat gain property procedures, improvements to the program are still necessary for it to meet user needs. Version 5, intended for release in late 1995, is being developed to meet these needs for increased accuracy, a flexible and state-of-the-art user interface, and the capabilities to handle more product types.

WINDOW 5 includes the capabilities to define and model the thermal performance of frames/dividers and their associated edge effects. Currently, such an analysis must be performed outside of WINDOW and requires simplifications to be made to frame profiles or is based on the use of generic frame and edge correlations. WINDOW's two-dimensional thermal model is composed of four sections: a graphical input, automatic grid generation, an finite-element analysis (FEA) solution, and the display of results. In the graphical input section, users are able to directly import a computer-aided design (CAD) drawing or a scanned image of a window profile, replicate its exact geometry, and assign material types and boundary conditions. The automatic grid generation is transparent to the user, with the exception of the requirement that complex shapes (i.e., an aluminum extrusion) be broken down into simpler polyshapes. Inclusion of an automatic grid generation makes detailed "true geometry" frame-and-edge heat-transfer analysis accessible to users without extensive knowledge of numerical methods of heat-transfer analysis. After the cross section is meshed it is sent to the FEA engine for solution and the results are returned. A postprocessor allows for the visual display of temperature and heat flux plots. Note that while this two-dimensional heat-transfer tool is being developed specifically for fenestration products, it also can be used to analyze other building envelope components.

WINDOW 5 also will include a built-in version of a national laboratory's program that allows the user to estimate the orientation-dependent annual energy impacts of a given window in a typical residence in various U.S. climates. This program is based on regressions to a database of DOE2.1 runs. Future versions will include a similar feature for commercial buildings.

Other technical additions include an improved angular/ spectral model for coated and uncoated glazings, the ability to analyze the optical properties of nonhomogeneous layers, and the ability to model the effects of laminated glazing layers. A door module permits the user to compute the total U-factors of exterior doors based on component U-factors calculated using the two-dimensional FEA module.

1 aFinlayson, Elizabeth, U.1 aArasteh, Dariush, K.1 aRubin, Michael, D.1 aSadlier, John1 aSullivan, Robert1 aHuizenga, Charlie1 aCurcija, Dragan, C.1 aBeall, Mark uhttps://facades.lbl.gov/publications/advances-thermal-and-optical01938nas a2200157 4500008004100000024001100041245003800052210003800090260003400128520145500162100001901617700002501636700002201661700002501683856007201708 1995 eng d aTA-34200aEdge Conduction in Vacuum Glazing0 aEdge Conduction in Vacuum Glazing aClearwater Beach, FLc03/19953 a

Vacuum glazing is a form of low-conductance double glazing using an internal vacuum between the two glass sheets to eliminate heat transport by gas conduction and convection. An array of small support pillars separates the sheets; fused solder glass forms the edge seal. Heat transfer through the glazing occurs by radiation across the vacuum gap, conduction through the support pillars, and conduction through the bonded edge seal. Edge conduction is problematic because it affects stresses in the edge region, leading to possible failure of the glazing; in addition, excessive heat transfer because of thermal bridging in the edge region can lower overall window thermal performance and decrease resistance to condensation.

Infrared thermography was used to analyze the thermal performance of prototype vacuum glazings, and, for comparison, atmospheric pressure superwindows. Research focused on mitigating the edge effects of vacuum glazings through the use of insulating trim, recessed edges, and framing materials. Experimentally validated finite-element and finite-difference modeling tools were used for thermal analysis of prototype vacuum glazing units and complete windows. Experimental measurements of edge conduction using infrared imaging were found to be in good agreement with finite-element modeling results for a given set of conditions. Finite-element modeling validates an analytic model developed for edge conduction.

1 aSimko, Tom, M.1 aCollins, Richard, E.1 aBeck, Fredric, A.1 aArasteh, Dariush, K. uhttps://facades.lbl.gov/publications/edge-conduction-vacuum-glazing02822nas 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)02508-102751nas a2200145 4500008003900000245012300039210006900162260001200231520219600243100002202439700002402461700001902485700002502504856007602529 1995 d00aAn Infrared Thermography-Based Window Surface Temperature Database for the Validation of Computer Heat Transfer Models0 aInfrared ThermographyBased Window Surface Temperature Database f c03/19953 a

Fenestration heat transfer simulation codes are used in energy performance rating and labeling procedures to model heat transfer through window systems and to calculate window U-values and condensation resistance factors. Experimental measurements of window thermal performance can direct the development of these codes, identify their strengths and weaknesses, set research priorities, and validate finished modeling tools. Infrared (IR) thermography is a measurement technique that is well suited to this task. IR thermography is a relatively fast, non-invasive, non-destructive technique that can resolve thermal performance differences between window components and window systems to a higher degree than a conventional hot box test. Infrared thermography provides spatial resolution of system performance by generating surface temperature maps of windows under controlled and characterized environmental conditions.

This paper summarizes basic theory and techniques for maximizing the accuracy and utility of infrared thermographic temperature measurements of window systems and components in a controlled laboratory setting. The physical setup of a complete infrared thermographic test facility at a major U.S. national research laboratory is described. Temperature measurement issues, and accuracy limits, for quantitative laboratory infrared thermography are discussed. An external reference emitter allows test-specific correction of absolute temperatures measured with an infrared scanner, resulting in 'an absolute measurement accuracy of ±O.5°C. Quantitative IR thermography is used to form a database of window surface temperature profiles for the validation of finite-element and finite-difference fenestration heat transfer modeling tools. An IR window surface temperature database with complete technical drawings of the windows tested; specification of all test window dimensions, materials, and thermal conductivities; environmental conditions of the tests with associated measurement errors; and two-dimensional surface temperature maps and selected cross sectional temperature profiles in a spreadsheet database format on an electronic media are presented.

1 aBeck, Fredric, A.1 aGriffith, Brent, T.1 aTurler, Daniel1 aArasteh, Dariush, K. uhttps://facades.lbl.gov/publications/infrared-thermography-based-window02245nas a2200157 4500008004100000024001200041245010600053210006900159260003400228520166300262100002401925700002201949700002501971700001901996856007202015 1995 eng d aUC-160000aIssues Associated with the Use of Infrared Thermography for Experimental Testing of Insulated Systems0 aIssues Associated with the Use of Infrared Thermography for Expe aClearwater Beach, FLc12/19953 a

Infrared scanning radiometers are used to generate temperature maps of building envelope components, including windows and insulation. These temperature maps may assist in evaluating components thermal performance. Although infrared imaging has long been used for field evaluations, controlled laboratory conditions allow improvements in quantitative measurements of surface temperature using reference emitter techniques.

This paper discusses issues associated with the accuracy of using infrared scanning radiometers to generate temperature maps of building envelope components under steady-state, controlled laboratory conditions. Preliminary experimental data are presented for the accuracy and uniformity of response of one commercial infrared scanner. The specified accuracy of this scanner for temperature measurements is 2 °C or 2% of the total range of values (span) being measured. A technique is described for improving this accuracy using a temperature-controlled external reference emitter. Minimum temperature measurement accuracy with a reference emitter is estimated at ±0.5 °C for ambient air and background radiation at 21.1 °C and surface temperatures from 0 °C to 21 °C.

Infrared imaging, with a reference emitter technique, is being used to create a database of temperature maps for a range of window systems, varying in physical complexity, material properties, and thermal performance. The database is to be distributed to developers of fenestration heat transfer simulation programs to help validate their models. Representative data are included for two insulated glazing units with different spacer systems.

1 aGriffith, Brent, T.1 aBeck, Fredric, A.1 aArasteh, Dariush, K.1 aTurler, Daniel uhttps://facades.lbl.gov/publications/issues-associated-use-infrared02870nas a2200157 4500008004100000050001400041245013200055210006900187260002900256520225900285100002202544700002402566700001902590700002502609856007802634 1995 eng d aLBL-3697500aUsing Infrared Thermography for the Creation of a Window Surface Temperature Database to Validate Computer Heat Transfer Models0 aUsing Infrared Thermography for the Creation of a Window Surface aToronto, Canadac06/19953 a

Infrared thermography is a non-invasive, non-destructive technique for measuring surface temperatures of an object. These surface temperatures can be used to understand the thermal performance of window components and complete window systems. Infrared (IR) thermography has long been used for qualitative field assessment of window thermal performance, and is now being used in the laboratory for quantitative assessments of window thermal performance. As windows become better and better, more refined test methods and/or simulation tools are required to accurately detect performance changes and make comparisons between products. While hot box calorimetery has worked well to characterize the thermal performance of conventional insulating products, differences in the thermal performance of new highly insulating systems are often less than the resolution of conventional hot box calorimeters. Infrared imaging techniques offer the opportunity to resolve small differences in the thermal performance of components of highly insulating window systems that hot box measurements are not able to identify.

Lawrence Berkeley Laboratory (LBL), a U.S. national research laboratory, is currently using infrared thermography to develop a database of measured surface temperature profiles for a number of different fenestration products for use in validating both basic and advanced two- and three-dimensional finite element method (FEM) and finite difference method (FDM) fenestration heat transfer simulation programs. IR surface temperature data, when taken under controlled laboratory conditions, can be used to direct the development of these simulation codes, identify their strengths and weaknesses, set research priorities, and validate finished modeling tools. Simulation of fenestration heat transfer is faster and less expensive than hot box testing of fenestration products, and forms the basis of window energy codes being implemented, developed, or considered in the US, Canada, the Former Soviet Union, Europe, and Australia. The National Fenestration Rating Council (U. S.) has developed a simulation-based standard which is used to rate and label window U-values for a published directory of over 10,000 different window products.

1 aBeck, Fredric, A.1 aGriffith, Brent, T.1 aTurler, Daniel1 aArasteh, Dariush, K. uhttps://facades.lbl.gov/publications/using-infrared-thermography-creation01932nas a2200169 4500008004100000050001400041245009300055210006900148300001200217490000700229520136600236100001901602700002101621700002301642700002101665856007601686 1994 eng d aLBL-3852500aCharacterization of Sol-Gel Deposited Niobium Pentoxide Films for Electrochromic Devices0 aCharacterization of SolGel Deposited Niobium Pentoxide Films for a433-4430 v363 a

Niobium pentoxide films, fabricated by the sol-gel process, were spin coated onto conductive indium tin oxide (ITO)/glass, and microscope slides. These films were cycled in a 1M LiClO4 propylene carbonate (PC) solution, and exhibited electrochromic behavior upon the electrochemical insertion (reduction) and extraction (oxidation) of lithium. In-situ optical transmittance measurements were investigated in the ultraviolet/visible/near-infrared wavelength regions (250-2100 nm). Niobium pentoxide films showed reversible optical switching from 320 to 870 nm, but were found electrochromically inactive in the infrared region. Surface analysis using X-ray photoelectron spectroscopy (XPS) indicated little difference in the chemistry of Nb2O5 films as deposited and lithiated LixNb2O5 films, as XPS binding energies of Nb and O showed no appreciable shifts. These films were found to be amorphous by X-ray diffraction. Optical transmittance measurements combined with cyclic voltamograms and XPS spectra, revealed that the electrochromic behavior of these films occurs due to the insertion of Li+ cations into niobium pentoxide films. The bronze coloration of the niobium pentoxide films could make them useful as an electrochromic counter electrodesfor electrochromic devices.

1 aÖzer, Nilgün1 aBarreto, Timothy1 aBuyuklimanl, Temel1 aLampert, Carl, M uhttps://facades.lbl.gov/publications/characterization-sol-gel-deposited02537nas 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-integrated01829nas a2200157 4500008004100000050001400041245011000055210006900165260002600234520122600260100002501486700002101511700003401532700002701566856007801593 1994 eng d aLBL-3445800aThe Design and Evaluation of Three Advanced Daylighting Systems: Light Shelves, Light Pipes and Skylights0 aDesign and Evaluation of Three Advanced Daylighting Systems Ligh aSan Jose, CAc06/19943 a

We present results from the design and evaluation of three advanced daylighting systems: a light shelf, a light pipe, and a skylight. These systems use optical films and an optimizedsgeometry to passively intercept and redirect sunlight further into the building. The objectives of these designs are to increase daylighting illuminance levels at distances of 4.6-9.1 m (15-30 ft) from the window, and to improve the uniformity of the daylight distribution and the luminance gradient across the room under variable sun and sky conditions throughout the year. The designs were developed through a series of computer-assisted ray-tracing studies, photometric measurements, and observations using physical scale models. Comprehensive sets of laboratory measurements in combination with analytical routines were then used to simulate daylight performance for any solar position. Results show increased daylight levels and an improved luminance gradient throughout the year - indicating that lighting energy consumption and cooling energy due to lighting can be substantially reduced with improvements to visual comfort. Future development of the designs may further improve the daylighting performance of these systems.

1 aBeltran, Liliana, O.1 aLee, Eleanor, S.1 aPapamichael, Konstantinos, M.1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/design-and-evaluation-three-advanced02740nas a2200181 4500008004100000050001900041245006200060210006200122260003100184520212100215100003402336700002502370700002102395700002102416700002702437700002302464856007102487 1994 eng d aLBL-35382 Rev.00aSimulating the Energy Performance of Holographic Glazings0 aSimulating the Energy Performance of Holographic Glazings aFreiburg, Germanyc04/19943 a

The light diffraction properties of holographic diffractive structures present an opportunity to improve the daylight performance in side-lit office spaces by redirecting and reflecting sunlight off the ceiling, providing adequate daylight illumination up to 30 ft (9.14 m) from the window wall. Prior studies of prototypical holographic glazings, installed above conventional view windows, have shown increased daylight levels over a deeper perimeter area than clear glass, for selected sun positions. In this study, we report on the simulation of the energy performance of prototypical holographic glazings assuming a commercial office building in the inland Los Angeles climate.

The simulation of the energy performance involved determination of both luminous and thermal performance. Since the optical complexity of holographic glazings prevented the use of conventional algorithms for the simulation of their luminous performance, we used a newly developed method that combines experimentally determined directional workplane illuminance coefficients with computer-based analytical routines to determine a comprehensive set of daylight factors for many sun positions. These daylight factors were then used within the DOE-2.1D energy simulation program to determine hourly daylight and energy performance over the course of an entire year for four window orientations.

Since the prototypical holographic diffractive structures considered in this study were applied on single pane clear glass, we also simulated the performance of hypothetical glazings, assuming the daylight performance of the prototype holographic glazings and the thermal performance of double-pane and low-e glazings. The results of our analyses show that these prototypical holographic glazings did not save significant electric energy or reduce peak electricity demand compared to conventional energy-efficient window systems in inland Los Angeles office buildings, mainly because of their low diffraction efficiency. Finally, we address various design and implementation issues towards potential performance improvement.

1 aPapamichael, Konstantinos, M.1 aBeltran, Liliana, O.1 aFurler, Reto, A.1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E.1 aRubin, Michael, D. uhttps://facades.lbl.gov/publications/simulating-energy-performance02087nas a2200181 4500008004100000024001100041245006100052210005700113260001200170520150200182100003401684700002501718700002101743700002101764700002701785700002301812856007001835 1993 eng d aDA-30200aThe Energy Performance of Prototype Holographic Glazings0 aEnergy Performance of Prototype Holographic Glazings c02/19933 a

We report on the simulation of the energy performance of prototype holographic glazings in commercial office buildings in a California climate. These prototype glazings, installed above conventional side windows, are designed to diffract the transmitted solar radiation and reflect it off the ceiling, providing adequate daylight illumination for typical office tasks up to 10m from the window. In this study, we experimentally determined a comprehensive set of solar-optical properties and characterized the contribution of the prototype holographic glazings to workplane illuminance in a scale model of a typical office space. We then used the scale model measurements to simulate the energy performance of the holographic glazings over the course of an entire year for four window orientations (North, East, South and West) for the inland Los Angeles climate, using the DOE-2.lD building energy analysis computer program. The results of our experimental analyses indicate that these prototype holographic glazings diffract only a small fraction of the incident light. The results of this study indicate that these prototype holographic glazings will not save energy in commercial office buildings. Their performance is very similar to that of clear glass, which, through side windows, cannot efficiently illuminate more than a 4m - 6m depth of a building`s perimeter, because the cooling penalties due to solar heat gain are greater than the electric lighting savings due to daylighting.

1 aPapamichael, Konstantinos, M.1 aBeltran, Liliana, O.1 aFurler, Reto, A.1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E.1 aRubin, Michael, D. uhttps://facades.lbl.gov/publications/energy-performance-prototype01773nas 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-value02011nas a2200133 4500008004100000050001400041245011500055210006900170260002400239520148000263100003401743700002501777856007501802 1993 eng d aLBL-3394500aSimulating the Daylight Performance of Fenestration Systems and Spaces of Arbitrary Complexity: The IDC Method0 aSimulating the Daylight Performance of Fenestration Systems and  aAdelaide, Australia3 a

A new method to simulate the daylight performance of fenestration systems and spaces is presented. This new method, named IDC (Integration of Directional Coefficients), allows the simulation of the daylight performance of fenestration systems and spaces of arbitrary complexity, under any sun, sky and ground conditions. The IDC method is based on the combination of scale model photometry and computer-based simulation. Physical scale models are used to experimentally determine a comprehensive set of directional illuminance coefficients at reference points of interest, which are then used in analytical, computer-based routines, to determine daylight factors or actual daylight illuminance values under any sun, sky and ground conditions.

The main advantage of the IDC method is its applicability to any optically complex environment. Moreover, the computer-based analytical routines are fast enough to allow for hourly simulation of the daylight performance over the course of an entire year. However, the method requires appropriate experimental facilities for the determination of the Directional Coefficients. The IDC method has been implemented and used successfully in inter-validation procedures with various daylight simulation computer programs. Currently, it is used to simulate the daylight performance of fenestration systems that incorporate optically complex components, such as Venetian blinds, optically treated light shelves and light pipes.

1 aPapamichael, Konstantinos, M.1 aBeltran, Liliana, O. uhttps://facades.lbl.gov/publications/simulating-daylight-performance-001768nas a2200133 4500008004100000050001400041245007200055210006900127490001600196520130200212100002201514700002501536856007301561 1993 eng d aLBL-3427100aA Validation of the WINDOW4/FRAME3 Linear Interpolation Methodology0 aValidation of the WINDOW4FRAME3 Linear Interpolation Methodology0 v100, Part 13 a

The validity of a method to reduce the total number of computer simulations which must be run to determine the U-values of a window product line with multiple glazing options is examined. The accuracy and limits of this method, which uses the WINDOW4 and FRAME simulation programs, is evaluated by comparing the edge, frame, and total window U-values calculated on the basis of single point FRAME simulations to those U-values as calculated on the basis of four point FRAME simulations combined with linear interpolation of frame and edge U-values by WINDOW4. The accuracy of this procedure is examined for two frame types, a low thermal conductivity wood-framed casement and a high thermal conductivity aluminum-framed casement, using both aluminum spacers and insulating spacers over a wide range of glazing types. The effect of center-of-glass U-value, overall glazing thickness and spacer type on frame and edge-of-glass U-values is discussed. It is shown that the agreement between total window U-values as calculated by the single point and four point simulation methods is better than 1% for double and triple-glazed windows with aluminum spacers, better than 1% for double-glazed windows with insulating spacers, and better than 2% for triple-glazed windows with insulating spacers.

1 aBeck, Fredric, A.1 aArasteh, Dariush, K. uhttps://facades.lbl.gov/publications/validation-window4frame3-linear02036nas a2200133 4500008004100000050001400041245010800055210006900163260002500232520152100257100002801778700002001806856007601826 1992 eng d aLBL-3503700aLarge Area Glare Sources and Their Effect on Discomfort and Visual Performance at Computer Workstations0 aLarge Area Glare Sources and Their Effect on Discomfort and Visu aHouston, TXc10/19923 a

This paper studies the effects of a large area light source of variable but uniform luminance surrounding a video display terminal (VDT) on the perceived glare discomfort and visual performance of computer operators. A set of criteria was established for rating the discomfort from glare as either intolerable, disturbing, noticeable, or imperceptible. Source luminance adjustments by means of a variable transformer to match the subjective glare criteria, as well as ratings of preselected lighting conditions on a visual analog scale with the same criteria, were used to determine comfortable lighting conditions. Results from the experiment indicate that subjects reliably selected a preferred lighting condition at any time when asked to adjust the luminance to produce optimum visual comfort. There was considerable between-subject variation in the range of luminances over which the surround field was neither noticeably too dim nor noticeably too bright. Comfortable luminance ranges also varied with initial presentation luminances immediately preceding the adjustment. Subjects preferred higher luminances following high initial presentation luminances. Performance speed at a difficult letter-counting task suggests that visual performance was slightly impaired by the presence of glare discomfort. Counting errors also occurred slightly more frequently under higher surround source luminances. There was a tendency for subjects to become more susceptible to glare over the course of the experiment.

1 aOsterhaus, Werner, K.E.1 aBailey, Ian, L. uhttps://facades.lbl.gov/publications/large-area-glare-sources-and-their