Glazings for the 21st Century - Windows and Daylighting Group

4Contributing EditorsRoss McCluneyFlorida Solar Energy CenterVoice:(407) 638-1414Fax: (407) 638-1010e-mail: rmccluney@fsec.ucf.eduWeb:http://www.fsec.ucf.edu/~fen/Jeff ChristianOak Ridge National LaboratoryVoice: (423) 574-5207Fax: (423) 574-9338e-mail: jef@ornl.govWeb:http://www.ornl.gov/ORNL/Energy_Eff/btc.htmlAl CzandernaNational Renewable EnergyLaboratoryVoice: (303) 384-6460Fax: (303) 384-6604e-mail: al_czanderna@nrel.govWeb: http://www.nrel.gov/Dragan CurcijaUniversity of MassachusettsVoice: (413) 545-2251Fax: (413) 545-1027e-mail: curcija@ecs.umass.eduWeb:http://www.ecs.umass.edu/mie/labs/berlJohn CarmodyMinnesota Building ResearchCenter1425 University Avenue SEMinneapolis MN 55455Voice: (612) 624-1351Fax: (612) 626-7424e-mail: carmo001@tc.unm.eduWeb:http://www.umn.edu/mnbrc/F A L LW I N T E R1 9 9 7LAWRENCE BERKELEYNATIONALLABORATORYENVIRONMENTALENERGYTECHNOLOGIES DIVISIONBUILDING TECHNOLOGIESPROGRAMWINDOWS & DAYLIGHTINGGROUPIntegrating Energy-Efficient FeaturesInto a Window/Wall Panel SystemTo integrate or to segregate?Residential windows combine acomplex set of material properties,mechanical mechanisms,and functional requirements.Windows must last many yearswhile keeping the elements out,the occupants comfortable, allowingdaylight in, and providingview out. All this in a packagethat can be easily and reliablyinstalled in a building envelope.Integrated Window SystemOngoing research in manysectors of the building industryhave created improvements inall areas of window design andfunction. To achieve the nextstep, researchers at BerkeleyLab are integrating several keyenergy-efficient features into awindow/wall panel, an IntegratedWindow System (IWS).The key elements of an IntegratedWindow include an exteriorsun shade to block the sun'sheat, and an interior insulationthat covers the window at nightto keep the warmth inside. Amanufactured construction approachincludes these energy-efficientfeatures in a full heightwall panel providing the wallstructure, the structural headerto transfer roof loads around thewindow, and a raceway for utilitiesrun under the window.Each of these elements addsmeasurable gains in comfort andthermal control to the building’soccupants that are more reliableand more useful than devices installedin the field. By placingthese elements in a manufacturedunit they can be employedto their optimum.ContactPaul LaBerge(510) 486-6830 Fax (510) 486-6099e-mail: P_LaBerge@lbl.govStriking Changesin Russian WindowProductionUntil recently, windows in Russianresidential buildings werelimited to three types: singleglazed, double-glazed, andtriple-glazed. Insulated glassunits were used on rare occasion,but only in municipalbuildings and in public transportation.This was of little concernwhen heat prices were low.In fact, the cost of energy wassuch that an investment to replacedouble-glazed with tripleglazedwindows would havehad a payback period of at least20 years.Striking changes have occurredin the field of windowproduction in Russia within thepast two years. Russia's transitionto a market economy, andthe sharp rises in prices of fueland energy have stimulated interestin energy-efficient windows.Based on a review ofRussian legislation on foreigninvestment, the most favorablecourse of action for foreign investorsin the construction sectoris probably the establishmentof joint ventures withRussian partners. The followingdevelopments are indicative ofthe changing market environment:• Adoped new Federal constructionstandards.• Established new voluntary certificationprogram by Ministryof Construction.• Increased Russian companies’manufacturing of new windowsby licensing foreign technology.• Russian companies producingglass and film with lowemissivitycoating with purchasesof foreign equipment.• In-country production capacityfor ordinary 3-6-millimeterglass is approximately 135-140million square meters per year,enough to meet current demand.• More than two billion squaremeters of buildings constructedsince 1961 need windowsreplaced to meet currentbuildings standards.• Market potential for IGUs estimatedat 24 million square feetper year. Currently, only 10 percentof this need is being met.• New construction in Moscowarea includes office buildings,business centers, and hotels, inpreparation for Moscow's 850thanniversary.ContactAlex SpiridonovSOLResearch Company,Moscow, Russia7 095 401-1960 Fax 7 095 482-4460e-mail: spiridon@santeh.msk.suFor more information, seehttp://www.pnl.gov/aisu/spiridon.htm .Moscow WorkshopPlanned for May 1998Avery successful joint meetingwas held in Moscow in May1997 between a U.S. team,comprised of DOE researchersand manufacturers, and a Russianteam, comprising code officialsand manufacturers. Afollow-upworkshop is planned forMay 1998 in Moscow.ContactJohn Hogan(206) 386-9145 Fax (206) 233-7883e-mail: john.hogan@ci.seattle.wa.usWilliam Dupont(202) 484-0887 Fax (202) 484-0888e-mail: Waupi@msn.com

U.S. Department of EnergyThe Electrochromics InitiativeIn 1995, the U.S. Department of Energy (DOE)launched an Electrochromics Initiative to accelerateresearch and development on electrochromicmaterials that would lead ultimately to commercialproducts. After issuing a competitive solicitationfor Phase One of the Initiative, the Departmentchose two manufacturers to develop electrochromicwindow prototypes, Optical CoatingLaboratory, Inc. (OCLI) of Santa Rosa, California,and the Donnelly Corporation of Tucson, Arizona.Berkeley Lab's role in this work is to providetechnical oversight of the Initiative for DOE, tosupply technical assistance to these companies, towork on improved materials for the coatings, andto assess the performance of electrochromic coatingsin buildings using simulation tools, fieldtests, and demonstration projects. Both vendorshave now delivered prototype windows of aboutone square foot in size. Berkeley Lab has conductedoptical characterization tests and Berkeley Labresearchers have also performed computer simulationsof the prototypes' energy and visual performanceusing, respectively, the DOE-2 and RADI-ANCE models. Al Czanderna's group at the NationalRenewable Energy Laboratory (NREL) hasbeen conducting durability tests on the samples(see article below). The results of the durabilitytests have proven useful in helping the Initiative'sindustrial partners improve their processes and definewhere the work will proceed in the Initiative'ssecond phase.ContactMike Rubin(510) 486-7124 Fax (510) 486-6099e-mail: MDRubin@lbl.govNational Renewable Energy LaboratoryDeveloping Testing Protocolfor Electrochromic WindowsThe National Renewable Energy Laboratory isleading the effort to develop a testing protocol forelectrochromic windows (ECWs). This protocolwill be ideal for testing electrochromic samples,such as the one-foot-square specimens now underdevelopment at Optical Coating Laboratory, Inc.(OCLI) and Donnelly Corporation. Visual inspectionand initial characterization for optical responseproperties are the first two steps of the protocol,followed by two tests, performed in parallel.For a thermal qualification test, the sampleswill be cycled between 76°C and -26°C at a cyclerate of five cycles per day (4.8 hours/cycle). Thesamples will not be exposed to solar radiation orhumidity, and they will not be switched during thetest, whose purpose is to establish that ECWs willsurvive the thermal cycling anticipated when theyare in service.In the temperature-radiation-cyclic I-V (currentvoltage) test, alkali halide lamps in an AtlasXR260 four-by-six-foot accelerated testing chamberwill irradiate the sample. These lamps are filteredto provide an AM 1.5 solar spectrum, includingUV radiation from 290 to 400 nm. The ECWslie in a horizontal plane, and a detector measuresirradiation intensity in this plane. The chamber'sair temperature is constant and is chosen to providea mean ECW coating temperature of 60°Cduring the test. Each device will receive the I-V itrequires for coloring and bleaching, generally inthe range of one to ten minutes per cycle. Irradiationby the alkali halide lamps increases the temperatureof the ECWs, especially in the coloredstate. Relative humidity in the chamber will bemeasured, but not controlled.ContactAl Czanderna(303) 384-6460 Fax (303) 384-6604e-mail: al_czanderna@nrel.govFlorida Solar Energy CenterComputationalAnalysis of ComplexFenestration SystemsRoss McCluney of the Florida Solar Energy Center,Coco, Florida, is leading the computationalpart of the effort to analyze complex fenestrationsystems.ASAPis a design and analysis computer programfor large optical systems that evaluates notonly specularly reflecting and transmitting elements,but diffuse surfaces as well. An ASAPusercan enter complex shading and other fenestrationsystem geometries, and specify a distribution,both geometric and spectral, of electromagneticradiation incident on the system. The programgenerates output data that characterizes the wholefenestration system as an object, and predicts thecomplete angular and spectral distributions of itsoptical properties.Since ASAPis an optical programming language,as well as a powerful computational tool, itshould be possible to prepare a custom versionadapted to the specific problem of calculating theoptical properties of complex fenestration systems.ContactRoss McCluneyFlorida Solar Energy Center(407) 783-0300 Fax (407) 783-2571e-mail: rmccluney@fsec.ucf.edu5MoWiTTTests ofElectrochromic PrototypesSmall-scale electrochromicprototypes from Donnellyand OCLI, participants inthe DOE/ElectrochromicInitiative, have recentlybeen tested in the MoWiTTfield test facility. The glazingswere incorporated intoskylight frames supplied byVelux. The summer testprogram included commerciallyavailable clear, tinted,and spectrally selectiveglazings as well. This projectrepresents the first useof MoWiTTfor skylighttesting and will providevaluable field experienceand performance data on energyflows and temperaturesexperienced by the skylightsand their glazing assemblies.ContactJoseph Klems(510) 486-5564Fax (510) 486-4089e-mail: JHKlems@lbl.govF A L LW I N T E R1 9 9 7LAWRENCE BERKELEYNATIONALLABORATORYENVIRONMENTALENERGYTECHNOLOGIES DIVISIONBUILDING TECHNOLOGIESPROGRAMWINDOWS & DAYLIGHTINGGROUP

6Fenestration Facts“The most promising smartwindow technology may bedevices based onelectrochromic coatings.Although not yet commerciallyavailable, they appearto have a good chance tomeet performance, cost, andmanufacturing requirementsthat would result in a marketablewindow system.”F A L LW I N T E R1 9 9 7Residential WindowsJohn Carmody et al1996LAWRENCE BERKELEYNATIONALLABORATORYENVIRONMENTALENERGYTECHNOLOGIES DIVISIONBUILDING TECHNOLOGIESPROGRAMWINDOWS & DAYLIGHTINGGROUPGlazing exists because of its optical clarityand light transmission properties. Increasinglyimportant is the ability of coatedglazing to control infrared and ultraviolet radiation.Dynamic coatings such as electrochromics,anisotropic and light-redirecting materials, geometricallycomplex insulation and shading systemswill control optical radiation in new ways.Optical and radiative properties of glazing materialstherefore are primaryinputs for determiningthe energy performanceof buildings. Accordingly,LBNLmaintains oneof the most extensive facilitiesin the world forcharacterizing the opticalproperties of glazingmaterials, includingseven specialized instrumentsand the analyticaltools needed to interpretthe results and extractuseful information.The Glazing OpticsCharacterization LaboratorySpecialized Equipment Helps Accurately Determine the Energy and VisualPerformance of Existing Products and Experimental Glazing MaterialsThe optical properties of simple glazing typessuch as coated and uncoated glass and plastic areconventionally tested at normal incidence (lightstrikes the glass at 90° to the surface). The NationalFenestration Rating Council (NFRC), with thetechnical assistance of LBNL, established proceduresthat provide for accurate measurement andcalculation of several different optical properties.These properties are then used in a nationwideprogram to rate and label the energy performanceof windows. As a result, all major U.S. glazingmanufacturers now follow a uniform characterizationprocedure. LBNL has collected and validatedspectral data for over 750 glazing products, anddistributes the data on a diskette or by downloadfrom our web site. The 5th release occurred inSeptember and is the first to include internationaldata, although it is not yet NFRC certified.The integrity of the glazing database is guaranteedboth by peer comparison and by checks ofeach file at LBNL. Atypical operation involvesthe measurement of product parameters neededfor calculations of SHGF, U-factor, and even annualenergy performance. Standard measurementsFigure 1. Ellipsometer determination of opticalindices.of spectral transmittance and reflectance at normalincidence are made with highly automatedspectrometers. APerkin-Elmer Lambda 19 withLabsphere RSA-19 integrating sphere is used forsolar range measurements on glazing products.Emittance is measured with a Nicolet FTIR with aCsI beamsplitter for extended range in the thermalinfrared. Under the auspices of the NFRC, glazingmanufacturers can measure their own materialsusing similar spectrometers.Significant error inthis type of measurement,however, is common,as shown by roundrobin studies among theNFRC manufacturers togetherwith the IEATask 18. If any featureof a spectrum appears tobe incorrect, more versatileand accurateequipment is employedas described below.With the basic ratingsystem working smoothly, the issue of propertiesneeded to calculate annual energy performancebecomes primary. Sunlight often strikes glass atoblique angles for which the transmittance and reflectanceare significantly different from their valuesat normal incidence. Areliable procedure forextrapolating from normal properties to obliqueproperties is thus needed for accurate annual energyperformance calculations. Several instrumentsare available to measure angle-dependent propertieswith high accuracy. Asingle-beam goniophotometeremploying a feedback-stabilized laserdiode with a short coherence length in conjunctionwith a large-area silicon detector provides absoluteverification at 670 nm and any angle of incidence.We also have a goniospectroradiometer describedin more detail below in connection withcomplex glazing. In principle, this instrument canmeasure all required angle-dependent properties,but accuracy is still an open issue. No standardprocedures or reference materials yet exist. Finally,we have a variable-angle spectroscopic ellipsometer(Fig. 1) which is used to determine fundamentaloptical constants of the glazings. These capabilities,however, do not exist in most industrial

821st Century Glazings ...(continued from page 1)Fenestration Facts“Avariant of the liquidcrystal display technologyused in wristwatches is nowserving as a privacy glazingfor new windows. Averythin layer of liquid crystalsis sandwiched between twotransparent electricalconductors on thin plasticfilms and the entire packageis laminated between twolayers of glass. When thepower is off, the liquidcrystals are in a random andunaligned state. Whenpower is applied, the electricfield in the devicealigns the liquid crystalsand the glazing becomesclear in a fraction of a second,permitting view inboth directions.”F A L LW I N T E R1 9 9 7Residential WindowsJohn Carmody et al1996LAWRENCE BERKELEYNATIONALLABORATORYENVIRONMENTALENERGYTECHNOLOGIES DIVISIONBUILDING TECHNOLOGIESPROGRAMWINDOWS & DAYLIGHTINGGROUPtime failure as well as to diagnoseand correct device problems(see page 5).Thin Film DepositionProcessesProcess modification for developmentof improved low-emittanceand solar control coatingscan be achieved through the useof advanced plasma technologydeveloped at LBNL. Anewtype of constricted glow-dischargeplasma source was recentlyselected for the prestigiousR&D 100 Award. Inventedby LBNL researchers AndreAnders, Mike Rubin, and MikeDickenson, the source was designedto be compatible with industrialvacuum depositionequipment and practice. Constructionis simple, rugged, andinexpensive. The source can operateindefinitely over a widerange of chamber pressure withoutany consumable parts suchas filaments or grids. Among theuses of the source are densificationof coatings for greater durability,crystallization at low temperaturesfor increased reflectivityor electrical conductivity, enhancementof reactivity to producean otherwise unstablephase or increase depositionrate, and control over composition.Several of these sourceshave been fabricated for specificuses by glazing manufacturers.LBNL will assist these manufacturersto optimize the sourcecharacteristics and to developnew coating types. Recently, alinear configuration was successfullytested. Consisting ofan array of miniaturized versionsof the original source, thislinear source is extendible to adeposition system of any width.International Collaborationon Optical MaterialsLBNLstaff continue to participateactively in several internationalforums under the auspicesof the International EnergySimulation tools, such as these RADIANCE ray tracing images, comparevisibility of a computer screen with conventional clear glass (lower left),tinted glass (lower right), and electrochromic glass (top left), using two differentcontrol strategies.Agency (IEA). LBNL led thesubtask on Chromogenics underIEATask 18 which concluded inMarch. Switchable glazing technologiessuch as liquid crystalsand thermochromics, as well aselectrochromics, were investigatedand compared. Asurveywas made of the companies involvedworldwide and the statusof their technology. Test methodsand results were comparedfor a variety of small sampletypes and some large electrochromics.Energy performanceof these technologieswas evaluated in another subtaskled by Bob Sullivan ofLBNL. Reports were producedon various specific technologiesand a final report will be availablelater this year. One newstudy used DOE-2 to evaluatethe performance of angle-selectiveprototypes developed byProf. Geoff Smith of the Universityof Technology at Sydney.(See the regular update onIEATask 18 on page 2).Materials CharacterizationStudiesCharacterization of these newglazing materials is an importantpart of our research. Structuraland compositional analysisis performed using a variety offacilites available at LBNL.These techniques range fromstandard techniques such as x-ray diffraction, or less commontechniques such as Nuclear ReactionAnalysis for detection oflithium in electrochromics, toexotic and unique applicationsof atomic resolution electronmicroscopy or the syncrotron atLBNL's Advanced LightSource. Amore complete listingand description of these generalmaterials science capabilitiesmay be found on LBNL's website, http://www.lbl.gov. Opticaland thermal characterization ofwindows are of particular importanceto our energy efficiencyprogram, so we maintainspecialized facilites in theseareas. Thermal facilites werehighlighted in previous issues.The Optical CharacterizationFacility for glazing is describedin detail in a separate article onpage 6.ContactMike Rubin(510) 486-7124 Fax (510) 486-6099e-mail: MDRubin@lbl.gov

Exciting New Publicationsfor the Building Industry9Fenestration FactsResidential Windows,A Guide to NewTechnologies and EnergyPerformanceJohn Carmody, StephenSelkowitz, Lisa HeschongAvailable from W. W. Norton &Company, paperback, 214 pp,1996, $22.00. Website orders:http://www.wwnorton.com/catalog/spring96/073004.htmAcomprehensive overviewof design principles, applicationsguide for windows andskylights, description of latesttechnology innovations andtheir energy impacts, and resourcematerials.ContactPat RossBuilding Technologies Program,Lawrence BerkeleyNational Laboratory,MS: 90-3111, Berkeley CA94720Fax (510) 486-4089e-mail: PLRoss@lbl.govTips for Daylightingwith Windows:The Integrated ApproachJennifer O'Connor, Eleanor Lee,Francis Rubinstein, StephenSelkowitz, BuildingTechnologies Program,Lawrence Berkeley NationalLaboratory, 1997.Apractical "how-to" guidefor applying daylighting strategiesin commercial buildings,with a systems integration perspective.Chapters include DaylightFeasibility, Envelope andRoom Decisions, Glazing Selections,Shading Strategy, MechanicalCoordination, LightingCoordination, Sensors and Controls,Calibration and Commissioning,Maintenance, and Cost-Benefit Analysis.Review the table of contentsand sample chapter under Publicationsat Building TechnologiesProgram’s web site:http://eande.lbl.gov/btp. Singlecopies of the document can bedownloaded in PDF formatfrom the web site. If you are interestedin reprinting the document,please contact us.ContactSteve SelkowitzFax (510) 486-4089e-mail: SESelkowitz@lbl.govSelecting Windows forEnergy EfficiencyThis 16-page brochure discussesthe new residential windowtechnologies that have increasedenergy benefits and comfort,providing more practical optionsfor consumers. Written as aguide for homeowners, architects,and builders, the brochureprovides guidance on the NationalFenestration RatingCouncil’s window energy ratingand labeling, design recommendations,and a valuable windowchecklist for design, specification,and installation.Review the table of contentsand download the document inPDF format from the BuildingTechnologies Program web site:http://eande.lbl.gov/btp.Copies are available fromEREC/Energy Efficiency andRenewable Energy Clearinghouse,P.O. Box 3048, Merrifield,VA22116 or call (800)363-3732, fax (703) 893-0440.If you are interested in reprintingthe brochure to include yourorganization’s identification,please contact us directly.ContactPat RossFax (510) 486-4089e-mail: PLRoss@lbl.gov“Adopt a holistic design approach,where the buildingis viewed as a whole andnot just a collection of parts.Common practice oftenfails to address the criticalinteractions between thebuilding facade (which admitsheat and light) and theelectric lighting system, resultingin an uncomfortableand ineffecient building thatis expensive and difficult toretrofit.”Tips for Daylightingwith Windows,The Integrated ApproachJennifer O’Connor et al1997F A L LW I N T E R1 9 9 7LAWRENCE BERKELEYNATIONALLABORATORYENVIRONMENTALENERGYTECHNOLOGIES DIVISIONBUILDING TECHNOLOGIESPROGRAMWINDOWS & DAYLIGHTINGGROUP

F A L LW I N T E R1 9 9 710Fenestration Facts“When shopping forwindows and skylights, payclose attention to whetherthe U-factor listed by themanufacturer applies to theglazing only or to the entireunit. If it is for the glazingonly, the overall U-factormay be considerably higherbecause of the frame andspacer effects. These effectsincrease with decreasingtotal window area.”Selecting Windows forEnergy EfficientyU.S. Department of Energy1997LAWRENCE BERKELEYNATIONALLABORATORYENVIRONMENTALENERGYTECHNOLOGIES DIVISIONBUILDING TECHNOLOGIESPROGRAMWINDOWS & DAYLIGHTINGGROUPRecent ResearchPublicationsElectrochromic Lithium NickelOxide by Pulsed LaserDepositionand Sputtering. 1996. Rubin M.,Wen S-H., Richardson T., Kerr J.,von Rottkay K., Slack J. SPIE InternationalSymposium on OpticalMaterials Technology for EnergyEfficiency and Solar Energy ConversionXV, Freiburg, Germany. Tobe published in Solar Energy Materialsand Solar Cells.Abstract: Thin films of lithiumnickel oxide were deposited bysputtering and pulsed laser deposition(PLD) from targets of pressedLiNiO 2 powder. The compositionand structure of these films wereanalyzed using a variety of techniques,such as nuclear-reactionanalysis, Rutherford backscatteringspectrometry (RBS), x-ray diffraction,infrared spectroscopy, andatomic force microscopy. Crystallinestructure, surface morphologyand chemical composition ofLi x Ni 1-x O thin films depend stronglyon deposition oxygen pressure,temperature, as well as substratetargetdistance. The films producedat temperatures lower than 600°Cspontaneously absorb CO 2 and H 2 Oat their surface once they are exposedto the air. The films depositedat 600°C proved to be stable inair over a long period. Even at roomtemperature the PLD films aredenser and more stable than sputteredfilms. RBS determined thecomposition of the best films to beLi 0.5 Ni 0.5 O deposited by PLD at 60mTorr O 2 pressure. Electrochemicaltests show that the films exhibit excellentreversibility in the range 1.0Vto 3.4 Vversus lithium. Electrochemicalformatting which is usedto develop electrochromism in otherfilms is not needed for the stoichiometricfilms. The optical transmissionrange is almost 70% at 550 nmfor 150-nm thick films. Devicesmade from these films were analyzedusing novel reference electrodesand by disassembly after cycling.Energy Performance of EvacuatedGlazings in Residential Buildings.1995. Sullivan R., Beck F.,Arasteh D., Selkowitz S. ASHRAETransactions 102(2) (1996). (LBL-37130 Rev.)Abstract: This paper presents theresults of a study investigating theenergy performance of evacuatedglazings or glazings which maintaina vacuum between two panes ofglass. Their performance is measuredby comparing results to prototypehighly insulated superwindowsas well as a more conventional insulatingglass unit with a low-Ecoating and argon gas fill. We usedthe DOE-2.1E energy analysis simulationprogram to analyze the annualand hourly heating energy usedue to the windows of a prototypicalsingle-story house located inMadison, Wisconsin. Cooling energyperformance was also investigated.Our results show that for highlyinsulating windows, the solar heatgain coefficient is as important asthe window's U-factor in determiningheating performance for windoworientations facing west-southeast.For other orientations inwhich there is not much direct solarradiation, the window's U-factorprimarily governs performance.The vacuum glazings had lowerheating requirements than the superwindowsfor most window orientations.The conventional low-Ewindow outperformed the superwindowsfor southwest-southsoutheastorientations. These performancedifferences are directlyrelated to the solar heat gain coefficientsof the various windows analyzed.The cooling performance ofthe windows was inversely relatedto the heating performance. Thelow solar heat gain coefficients ofthe superwindows resulted in thebest cooling performance. However,we were able to mitigate thecooling differences of the windowsby using an interior shading devicethat reduced the amount of solargain.Advanced Optical DaylightingSystems: Light Shelves and LightPipes. 1995. Beltrán L.O., LeeE.S., and Selkowitz S.E. 1996.IESNAAnnual Conference, August4-7, 1996, Cleveland, OH, and to beconsidered for publication in theJournal of the IES and Lighting Designand Application. (LBL-38133)Abstract: We present two perimeterdaylighting systems that passivelyredirect beam sunlight furtherfrom the window wall usingspecial optical films, an optimizedgeometry, and a small glazing aperture.The objectives of these systemsare (1) to increase daylight illuminancelevels at 4.6-9.1 m (15-30 ft) from the window aperturewith minimum solar heat gains and(2) to improve the uniformity of thedaylighting luminance gradientacross the room under variablesolar conditions throughout theyear. The designs were developedthrough a series of computer-assistedray-tracing studies, laser visualizationtechniques, and photometricmeasurements and observationsusing physical scale models. Bidirectionalilluminance measurementsin combination with analytical routineswere then used to simulatedaylight performance for any solarposition, and were incorporated intothe DOE-2.1E building energy analysiscomputer program to evaluateenergy savings. Results show increaseddaylight levels and an improvedluminance gradient throughoutthe year compared to conventionaldaylighting systems.Surface Temperatures of InsulatedGlazing Units: Infrared ThermographyLaboratory Measurements.1995. Griffith B.T., TürlerD., and Arasteh D. 1996 ASHRAETransactions 102(2), San Antonio,TX. (LBL-38117)Abstract: Data are presented forthe distribution of surface temperatureson the warm-side surface ofseven different insulated glazingunits. Surface temperatures aremeasured using infrared thermographyand an external referencingtechnique. This technique allowsdetailed mapping of surface temperaturesthat is non-intrusive. Theglazings were placed between warmand cold environmental chambersthat were operated at conditionscorresponding to standard designconditions for winter heating. Thetemperature conditions are 21.1°C(70°F) and -17.8°C (0°F) on thewarm and cold sides, respectively.Film coefficients varied somewhatwith average conditions of about7.6 W/m 2. K (1.34 Btu/h . ft 2.° F) forthe warm-side and 28.9 W/m 2. K(5.1 Btu/h . ft 2.° F) for the cold-side.Surface temperature data are plottedfor the vertical distribution alongthe centerline of the IG and for thehorizontal distribution along thecenterline. This paper is part of alarger collaborative effort that studiedthe same set of glazings.For copies contactPat Ross(510) 486-6845 Fax (510) 486-4089e-mail: PLRoss@lbl.govhttp://eande.lbl.gov/btp

UserFacilitiesIndustry is invited to collaboratein the use of these facilities. Ineach issue of FenestrationR&D we will take a closer lookat one of our user facilities.Please contact the individual researcherlisted under each facilityto discuss potential use.❐ Mobile Window Thermal TestFacility (MoWiTT) The MoWiTTfacility contains two highly instrumented,side-by-side calorimetrictest chambers that are used to testwindow and wall elements underactual outdoor conditions. The facilitymay be rotated to face in anydirection and is currently located inReno, Nevada, which experiencesboth summer and winter extremeclimate conditions. It can directlymeasure solar heat gain and can beused to determine window andshading system properties for awide variety of solar control options.With 200 data channels collectingdata every few seconds, thefacility can directly measure coolingload shapes on peak summerdays with excellent time resolution.The facility can also be used to validatecomputer models and to comparevarious technologies in realtime. Industry has used MoWiTTresults to justify new product development.ContactJoseph Klems(510) 486-5564 Fax (510) 486-4089e-mail: JHKlems@LBL.gov❐ IR Camera Test Facility Thisfacility includes a high-resolution,infrared imaging camera, a computerprocessor/printer, and a cold/hotchamber to hold samples for testing.The camera system is portableand can measure surface temperaturesthat can then be correlated tovarious heat loss or gain parameters.The IR camera is useful for assessingheat loss from existingbuildings in the field as well asfrom building components and appliancesin the laboratory setting.ContactBrent Griffith(510) 486-6061 Fax (510) 486-4089e-mail: BTGriffith@LBL.gov❐ Thin-Film Materials LaboratoryThis laboratory includes a widerange of apparatus to deposit andanalyze thin-film coatings for energycontrol purposes. The laboratory’sthin-film deposition systemsare used to make new types of selectiveand electrochromic coatings.The laboratory also includes spectrophotometersto measure solar,near IR, and far IR properties.ContactMike Rubin(510) 486-7124 Fax (510) 486-6099e-mail: MDRubin@LBL.gov❐ Sky Simulator The 24-foot-diametersky simulator is a hemisphericalfacility used to test daylightingperformance in scalemodelbuildings under controlledand reproducible conditions. Computerizedcontrol of light sourceswithin the hemisphere can createluminous distributions typical ofclear, uniform, or overcast skiesrepresentative of any desired location,orientation, climate, and seasonon Earth. It can also be used asa sun simulator to test shadingstrategies in scale models up to 1.5square meters in size. Light levelswithin the models are measured by60 photosensors and the measurementsare used to predict daylightilluminance conditions within fullsizedbuildings.ContactStephen Selkowitz(510) 486-5064 Fax (510) 486-4089e-mail: SESelkowitz@LBL.gov❐ Solar Heat Gain Scanner Thisdevice is used to characterize thecomplex optical properties of glazingsand shading systems that aregeometrically complex, such asvenetian blinds. The system measurestransmitted and reflected energyand light at all incidence andoutgoing angles. The scanner hasbeen used to develop a new procedureto predict solar heat gainthrough complex shading systems.ContactJoseph Klems(510) 486-5564 Fax (510) 486-4089e-mail: JHKlems@LBL.govSoftwareAvailable❐ ADELINE 2.0 analyzes lightingenergy savings in buildings that utilizedaylighting. Its unique collectionof software tools for the MS-DOS platform includes Radiancev2.4, Superlite 2.0 IEA, Scribe (a3D editor for simple scenes), and aWindows-like graphical user interfacethat ties these tools together.The package comes with an extensive475 page manual in a looseleaf3-ring binder, context-sensitivehelp menus, online hyper-text help,and installs from CD-ROM.ContactCharles EhrlichFAX (510) 486-4089e-mail: CKEhrlich@lbl.govWeb: http://radsite.lbl.gov/adeline/HOME.html❐ RESFEN 3.0 is a WINDOWS95 (or NT)-based PC program forcalculating residential fenestrationheating and cooling energy use andcosts. This new program (whichuses the DOE-2 calculation engine)is currently being evaluated for possibleuse as part of a window ratingsystem being developed by the NationalFenestration Rating Council(NFRC).❐ SUPERLITE 2.0 is a PC programthat calculates daylight illuminancedistributions for complexroom and light source geometrieswith tested accuracy. SUPERLITEwill model daylight coming throughas many as five openings and beingreflected from as many as 20opaque surfaces oriented in any direction.❐ WINDOW 4.1 is a thermalanalysis PC program that is the defacto standard used by U.S. manufacturersto characterize productperformance. The program is usedby the National Fenestration RatingCouncil as the basis for developmentof energy rating labels forwindows.❐ THERM 1.0 is a MicrosoftWindows-based 2D heat transferanalysis tool, based on finite elementanalysis and can model twodimensionalheat transfer with aminimum of simplifications toexact cross-section geometries.ContactPat Ross(510) 486-6845 Fax (510) 486-4089e-mail: PLRoss@LBL.gov11The Fenestration R&Dnewsletter provides a periodicupdate on U.S. Departmentof Energy-sponsoredwindows and glazings researchat Lawrence BerkeleyNational Laboratory, aswell as other DOE-supportedactivities at Florida SolarEnergy Center, NationalRenewable Energy Laboratory,Oak Ridge NationalLaboratory, University ofMassachusetts, and TuftsUniversity.Fenestration R&D ismade possible with supportfrom the U.S. Departmentof Energy, Assistant Secretaryfor Energy Efficiencyand Renewable Energy, Officeof Building Technology,State and CommunityPrograms, Office of BuildingSystems.Samuel J. TaylorProgramManager, Building Systemsand Materials DivisionLBNL’s Windows andDaylighting Group developsadvanced optical materials,studies fenestrationperformance, and createscomputer-based tools andapplications guides for improvingthe energy-relatedperformance of windows.Stephen E. SelkowitzProgram Head, BuildingTechnologiesF A L LW I N T E R1 9 9 7LAWRENCE BERKELEYNATIONALLABORATORYENVIRONMENTALENERGYTECHNOLOGIES DIVISIONBUILDING TECHNOLOGIESPROGRAMWINDOWS & DAYLIGHTINGGROUP

12PUB-762 Fall/Winter 1997-5000This work was supported by the U.S. Departmentof Energy under Contract No.DE-AC03-76SF00098Environmental EnergyTechnologies DivisionLawrence Berkeley National LaboratoryUniversity of CaliforniaBerkeley, CA94720 USAAn Equal Opportunity EmployerThis document was prepared as an accountof work sponsored by the UnitedStates Government. While this documentis believed to contain correct information,neither the United States Government norany agency thereof, nor The Regents ofthe University of California, nor any oftheir employees, makes any warranty, expressor implied, or assumes any legal responsibilityfor the accuracy, completeness,or usefulness of any information, apparatus,product, or process disclosed, orrepresents that its use would not infringeprivately owned rights. Reference hereinto any specific commercial product, process,or service by its trade name, trademark,manufacturer, or otherwise, doesnot necessarily constitute or imply its endorsement,recommendation, or favoringby the United States Government or anyagency thereof, or The Regents of theUniversity of California. The views andopinions of authors expressed herein donot necessarily state or reflect those of theUnited States Government or any agencythereof, or The Regents of the UniversitySponsors of research describedin this issue include:California Institute for Energy EfficiencyU.S. Department of EnergyFederal Energy Management ProgramOffice of Building TechnologiesFenestration R&D is made possiblewith support from the U.S. Departmentof Energy, Assistant Secretaryfor Energy Efficiency andRenewable Energy, Office of BuildingTechnology, State and CommunityPrograms, Office of BuildingSystems, Building Systems and MaterialsDivision, Samuel J. Taylor,program manager.NFRCUpdateNational Fenestration Rating CouncilNew Image for NFRCIt’s official! The NFRC membership overwhelminglyadopted a new logo at the Spring 1997Membership Meeting in Nashville, Tennessee.The new multi-faceted logo reflects the manydifferent aspects of NFRC’s mission. The newlogo emphasizes the importance of both heatingand cooling performance of fenestration. Thequadrant design gives the appearance of a window,while symbolizing different climate regions.The new logo will begin to appear immediatelyon all NFRC promotional and marketing materials.NFRC-100 RevisedIn an effort to streamline certification procedures,NFRC has revised NFRC-100: Procedurefor Determining Fenestration Product ThermalProperties. Instead of requiring two separate teststo determine U-Factor values, manufacturers cannow validate their values through one initial test.U-Factor measures a product’s entire ability totransfer heat from inside the home to the outside.New Heating and Cooling RatingsUnder DevelopmentAt its spring, summer, and fall 1997 meetings,NFRC continued its efforts to develop consumerfriendlyheating and cooling ratings. The ratingswill make window shopping easier for consumersand builders, without sacrificing technological excellence.These ratings will provide energy performanceinformation in just two numbers—one describingperformance during the winter heating season, andthe other during the summer cooling season. Thenumbers, given on a scale from 0 to 10, will allowquick, accurate comparisons of the energy performanceof different products.NFRC Meeting ScheduleJanuary 21-22, 1998NFRC Task Group MeetingsHoliday Inn San Francisco AirportSan Francisco, CaliforniaMarch 29-April 2, 1998NFRC Spring MeetingLoews Annapolis HotelAnnapolis, MarylandFor more information on:• Administrative & Membership• Certification Agency Program• Communication and Education• Compliance Assurance Program• Laboratory Accreditation Program• Meetings/Newsletters• Product Certification Program• Publication OrdersContactNational Fenestration Rating Council1300 Spring Street, Suite 500Silver Spring, MD 20910 USATel: (301) 589-NFRCFax: (301) 588-0854e-mail: NFRCUSA@aol.comWeb: http://www.nfrc.orgBuilding Technologies ProgramEnvironmental Energy Technologies DivisionLawrence Berkeley National LaboratoryOne Cyclotron Road, Mailstop 90-3111Berkeley, CA94720 USAFirst ClassU.S. PostagePAIDBerkeley, CAPermit No. 1123Printed on recycled paper.Please recycle again