00869nas a2200109 4500008003900000245004400039210004400083260001200127520052400139100002200663856007400685 2013 d00aComplex Fenestration Calculation Module0 aComplex Fenestration Calculation Module c10/20133 a

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

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

The remainder of the document focuses on individual models.

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/complex-fenestration-calculation02555nas a2200205 4500008003900000245009100039210006900130260001200199300001200211490000800223520188300231100002102114700002902135700002202164700002202186700002002208700002102228700002202249856007802271 2009 d00aField Measurements of Innovative Indoor Shading Systems in a Full-Scale Office Testbed0 aField Measurements of Innovative Indoor Shading Systems in a Ful c10/2009 a706-7280 v1153 a

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E.1 aDiBartolomeo, Dennis, L.1 aKlems, Joseph, H.1 aClear, Robert, D.1 aKonis, Kyle, S.1 aKonstantoglou, Maria1 aPerepelitza, Mark uhttps://facades.lbl.gov/publications/innovative-fa-ade-systems-low-energy02585nas a2200205 4500008004100000245005400041210005100095260006100146300001000207520191200217100002002129700002202149700002202171700002302193700002502216700002202241700001602263700002402279856007602303 2008 eng d00aWINDOW 6.2/THERM 6.2 Research Version User Manual0 aWINDOW 62THERM 62 Research Version User Manual aBerkeleybLawrence Berkeley National Laboratoryc01/2008 a1-1263 a

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

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

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

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

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

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

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

1 aMitchell, Robin1 aKohler, Christian1 aKlems, Joseph, H.1 aRubin, Michael, D.1 aArasteh, Dariush, K.1 aHuizenga, Charlie1 aYu, Tiefeng1 aCurcija, Dragan, C. uhttps://facades.lbl.gov/publications/window-62therm-62-research-version01663nas a2200325 4500008004100000024002100041245004200062210004200104260001200146520070300158653002500861653001300886653002500899653002700924653002200951653001800973653001600991653002301007653001901030100002101049700002701070700002201097700002901119700002201148700002401170700002201194700002401216700002101240856007601261 2006 eng d aCEC-500-2006-05200aAdvancement of Electrochromic Windows0 aAdvancement of Electrochromic Windows c04/20063 a

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

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

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

1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E.1 aClear, Robert, D.1 aDiBartolomeo, Dennis, L.1 aKlems, Joseph, H.1 aFernandes, Luis, L.1 aWard, Gregory, J.1 aInkarojrit, Vorapat1 aYazdanian, Mehry uhttps://facades.lbl.gov/publications/design-guide-early-market02228nas a2200205 4500008004100000245010200041210006900143260003300212490001600245520148700261653003701748653002201785653002501807100002101832700002901853700002201882700002101904700002701925856007001952 2006 eng d00aMonitored Energy Performance of Electrochromic Windows Controlled for Daylight and Visual Comfort0 aMonitored Energy Performance of Electrochromic Windows Controlle aQuebec City, Canadac10/20060 v112 Issue 23 a

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

10abuilding automation and controls10aBuilding envelope10acommercial buildings1 aLee, Eleanor, S.1 aDiBartolomeo, Dennis, L.1 aKlems, Joseph, H.1 aYazdanian, Mehry1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/monitored-energy-performance01168nas a2200133 4500008004100000050001500041245004900056210004900105260002900154490001600183520073800199100002200937856007500959 2002 eng d aLBNL-5145300aMeasured Winter Performance of Storm Windows0 aMeasured Winter Performance of Storm Windows aKansas City, MOc07/20030 v109, Part 23 a

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

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/measured-winter-performance-storm01286nas a2200145 4500008004100000050001500041245005500056210005500111260002500166300001200191490001600203520082500219100002201044856007401066 2001 eng d aLBNL-4883500aSolar Heat Gain through a Skylight in a Light Well0 aSolar Heat Gain through a Skylight in a Light Well aChicago, ILc01/2003 a512-5240 v108, Part 13 a

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

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/solar-heat-gain-through-skylight01152nas a2200109 4500008004100000050001500041245011700056210006900173520069900242100002200941856007900963 2000 eng d aLBNL-4668200aSolar Heat Gain Through Fenestrations Containing Shading: Procedures for Estimating Performace from Minimal Data0 aSolar Heat Gain Through Fenestrations Containing Shading Procedu3 a

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

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/solar-heat-gain-through-fenestrations01115nas a2200121 4500008004100000245004100041210004000082260003600122490001600158520072200174100002200896856007500918 2000 eng d00aU-Values of Flat and Domed Skylights0 aUValues of Flat and Domed Skylights aMinneapolis, Minnesotac06/20000 v106, Part 23 a

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

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/u-values-flat-and-domed-skylights00858nas a2200133 4500008004100000050001500041245006800056210006800124300001100192490000700203520041500210100002200625856007700647 1999 eng d aLBNL-4282500aNet Energy Performance Measurements on Electrochromic Skylights0 aNet Energy Performance Measurements on Electrochromic Skylights a93-1020 v333 a

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

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

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

1 aKlems, Joseph, H.1 aFinlayson, Elizabeth, U.1 aOlsen, Thomas, H.1 aBanks, David, W1 aPallis, Jani, M. uhttps://facades.lbl.gov/publications/toward-virtual-building-laboratory01287nas a2200133 4500008004100000050001500041245005500056210005400111260003100165490001600196520084400212100002201056856007501078 1997 eng d aLBNL-4044800aGreenhouse Window U-Factors Under Field Conditions0 aGreenhouse Window UFactors Under Field Conditions aSan Francisco, CAc01/19980 v104, Part 13 a

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

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/greenhouse-window-u-factors-under01177nas a2200145 4500008004100000050001500041245011000056210006900166260003000235490001600265520062700281100002200908700002400930856007700954 1996 eng d aLBNL-3924800aSolar Heat Gain Coefficient of Complex Fenestrations with a Venetian Blind for Differing Slat Tilt Angles0 aSolar Heat Gain Coefficient of Complex Fenestrations with a Vene aPhiladelphia, PAc01/19970 v103, Part 13 a

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

1 aKlems, Joseph, H.1 aWarner, Jeffrey, L. uhttps://facades.lbl.gov/publications/solar-heat-gain-coefficient-complex01286nas a2200133 4500008004100000050001400041245009700055210006900152490001600221520079900237100002201036700002001058856007401078 1995 eng d aLBL-3703800aCalorimetric Measurements of Inward-Flowing Fraction for Complex Glazing and Shading Systems0 aCalorimetric Measurements of InwardFlowing Fraction for Complex 0 v102, Part 13 a

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

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

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

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

1 aKlems, Joseph, H.1 aWarner, Jeffrey, L.1 aKelley, Guy, O. uhttps://facades.lbl.gov/publications/comparison-between-calculated-and00835nas a2200145 4500008004100000050001400041245004700055210004700102260003400149520037100183100002200554700002100576700002000597856007200617 1995 eng d aLBL-3774700aMeasured Performance of Selective Glazings0 aMeasured Performance of Selective Glazings aClearwater Beach, FLc12/19953 a

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

1 aKlems, Joseph, H. uhttps://facades.lbl.gov/publications/new-method-predicting-solar-heat-001559nas a2200097 4500008004100000245006100041210006000102520119800162100002201360856007901382 1992 eng d00aNet Energy Performance Measurements on Two Low-E Windows0 aNet Energy Performance Measurements on Two LowE Windows3 a

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

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

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

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

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