02120nas a2200169 4500008004100000022001400041245009400055210006900149260001200218300001400230490000800244520157100252100001901823700002101842700002301863856006401886 2017 eng d a0360-132300aDaylight performance of a microstructured prismatic window film in deep open plan offices0 aDaylight performance of a microstructured prismatic window film c02/2017 a280–2970 v1133 a
Daylight redirecting systems with vertical windows have the potential to offset lighting energy use in deep perimeter zones. A microstructured prismatic film designed for such use was characterized using goniophotometric measurements and ray tracing simulations. The synthetically-generated bidirectional scattering distribution function (BSDF) data were shown to have good agreement with limited measured data for normal incident angles (0–60°). Measured data indicated that the prismatic film was most efficient when vertical angles of incidence were between 18 and 35° and within ±45° of normal incidence to the plane of the window so maximum energy savings across the full depth of the zone occurred over the equinox to winter solstice period. Annual lighting energy use and visual comfort in a deep open plan office zone were evaluated using the Radiance three-phase method in several climates and for south and east-facing window orientations. Lighting energy savings were 39–43% for a 12 m (40 ft) deep south-facing perimeter zone compared to the same zone with no lighting controls. The prismatic film with and without a diffuser controlled glare for views parallel to the window but produced glare for seated viewpoints looking toward the window. At mature market costs, the system was projected to have a simple payback of 2–6 years. Technical challenges encountered throughout the evaluation led to improvements in measurement and modeling tools and stressed the importance of having accurate input data for product development.
1 aMcNeil, Andrew1 aLee, Eleanor, S.1 aJonsson, Jacob, C. uhttps://facades.lbl.gov/publications/daylight-performance-002919nas a2200181 4500008004100000245011300041210006900154260001200223520228500235100002102520700002402541700001802565700002702583700001702610700001802627700002002645856007202665 2017 eng d00aDemonstration of Energy Efficient Retrofits for Lighting and Daylighting in New York City Office Buildings0 aDemonstration of Energy Efficient Retrofits for Lighting and Day c04/20173 aThe U.S. Department of Energy's (DOE) Commercial Buildings Integration (CBI) program's mission (and that of the New York State Energy Research & Development Authority (NYSERDA)) is to accelerate the adoption of cost-effective, underutilized building technologies with large energy savings potential. The key question which CBI asks for each high impact technology is: "What can the DOE do to improve the market adoption of this technology?" Answering this relies on an assessment of the most significant barriers, including:
Innovative, automated shading and LED lighting controls were identified as key technologies that have the potential to significantly reduce perimeter zone energy use and peak demand in existing commercial buildings. Technological advances in the field of low-cost embedded controls have enabled high-resolution sensing and more optimal control on a per fixture or shade basis. The Lawrence Berkeley National Laboratory (LBNL) partnered with the Building Energy Exchange (BEEx) and a commercial building owner to evaluate leading-edge technologies on a 40,000 ft2 floor in an occupied, high-rise commercial office building in New York, New York. This “Living Laboratory” was monitored for a year prior to and six months following the installation of four sets of lighting and shading technologies and their performance was compared to a parallel reference floor in the same building.
The Living Laboratory demonstrated that there were many competitive products on the market, that the products were able to meet current needs, and that the various advanced features provided significant added value over and above that of conventional products. Monitored data provided detailed insights into how and why each technology performed the way it did, and what the impacts were on energy-efficiency, peak demand, visual and thermal comfort, indoor environmental quality, and occupant acceptance and satisfaction within the resultant environment.
1 aLee, Eleanor, S.1 aFernandes, Luis, L.1 aWang, Taoning1 aSelkowitz, Stephen, E.1 aMesh, Steven1 aFrank, Yetsuh1 aYancey, Richard uhttps://facades.lbl.gov/publications/demonstration-energy-efficient00763nas a2200205 4500008003900000245011500039210006900154260003100223653002400254653003300278653002400311653002100335653002500356653001300381100002100394700001900415700002100434700002300455856007900478 2015 d00aDiscomfort glare with complex fenestration systems and the impact on energy use when using daylighting control0 aDiscomfort glare with complex fenestration systems and the impac aBern, Switzerlandc11/201510abuilding simulation10aComplex fenestration systems10adaylighting control10aDiscomfort Glare10aEnergy Use Intensity10aradiance1 aHoffmann, Sabine1 aMcNeil, Andrew1 aLee, Eleanor, S.1 aKalyanam, Raghuram uhttps://facades.lbl.gov/publications/discomfort-glare-complex-fenestration01036nas a2200169 4500008003900000022001400039245008800053210006900141260001200210300001600222490000700238520048400245100001900729700001700748700002200765856007900787 2014 d a0093-381300aDrifting Ionization Zone in DC Magnetron Sputtering Discharges at Very Low Currents0 aDrifting Ionization Zone in DC Magnetron Sputtering Discharges a c10/2014 a2578 - 25790 v423 aDischarges with crossed electric and magnetic fields are known to develop instabilities that are crucial in the transport of charged particles. Sputtering magnetrons are no exception. While most recent studies focused on traveling ionization zones in high power impulse magnetron sputtering, we show here fast camera images of magnetron discharges at very low current. A single drifting ionization zone is always present, even down to the threshold current of about 10 mA.
1 aAnders, André1 aNi, Pavel, A1 aAndersson, Joakim uhttps://facades.lbl.gov/publications/drifting-ionization-zone-dc-magnetron01223nas a2200133 4500008004100000245009400041210006900135260001200204520073200216100001900948700002100967700002300988856007801011 2013 eng d00aDaylight performance of a microstructured prismatic window film in deep open plan offices0 aDaylight performance of a microstructured prismatic window film c09/20133 aDaylight redirecting systems with vertical windows have the potential to offset lighting energy use in deep perimeter zones. A microstructured prismatic film was designed and fabricated by a manufacturer to redirect sunlight to the ceiling plane when the film was installed in the upper portion of a window. Energy simulations based on the raytracing program, Radiance, were performed to evaluate the annual lighting energy use and discomfort glare in a deep open plan office zone in several climates and for south and east-facing window orientations. These simulations showed that when the prismatic film was combined with a light diffusing film, the system was able to deliver significant energy savings without glare.
1 aMcNeil, Andrew1 aLee, Eleanor, S.1 aJonsson, Jacob, C. uhttps://facades.lbl.gov/publications/daylight-performance-microstructured00399nas a2200109 4500008004100000245005700041210005600098260001200154100002400166700002100190856007800211 2013 eng d00aDesigning improved angular-selective shading systems0 aDesigning improved angularselective shading systems c09/20131 aFernandes, Luis, L.1 aLee, Eleanor, S. uhttps://facades.lbl.gov/publications/designing-improved-angular-selective01455nas a2200253 4500008003900000022001300039245012000052210006900172260001200241300001100253490000800264520065900272653002000931653001500951653002200966653002300988653001501011100001901026700002101045700001801066700002201084700001801106856007701124 2013 d a0003695100aDrifting potential humps in ionization zones: The “propeller blades” of high power impulse magnetron sputtering0 aDrifting potential humps in ionization zones The propeller blade c10/2013 a1441030 v1033 aIon energy distribution functions measured for high power impulse magnetron sputtering show features, such as a broad peak at several 10 eV with an extended tail, as well as asymmetry with respect to E × B, where E and B are the local electric and magnetic field vectors, respectively. Here it is proposed that those features are due to the formation of a potential hump of several 10 V in each of the traveling ionization zones. Potential hump formation is associated with a negative-positive-negative space charge that naturally forms in ionization zones driven by energetic drifting electrons.
10aElectric fields10aionization10aplasma ionization10asputter deposition10asputtering1 aAnders, André1 aPanjan, Matjaž1 aFranz, Robert1 aAndersson, Joakim1 aNi, Pavel, A. uhttps://facades.lbl.gov/publications/drifting-potential-humps-ionization01397nas a2200145 4500008004100000245013200041210006900173260001200242300000700254520084000261100003101101700001901132700002101151856007901172 2012 eng d00aDevelopment of a simulation-based controls framework for implementation of controls algorithms for complex fenestration systems0 aDevelopment of a simulationbased controls framework for implemen c09/2012 a153 aEffectively controlled dynamic windows can substantially reduce the energy consumption of buildings. Unfortunately, modular and extensible frameworks for testing and evaluating window system control algorithms that include the effects of thermal mass are missing in the research community.
This paper describes a modular and extensible simulation-based framework that uses different simulation tools such as EnergyPlus, Modelica, Radiance, and the Building Controls Virtual Test Bed (BCVTB) to develop and evaluate the performance of integrated façade control strategies. We present a simulation framework and a proof-of concept application using the framework to control a venetian blind in a physical test cell in order to reduce its zone thermal load based on solar inputs and internal gains measured at the test cell.
1 aNouidui, Thierry, Stephane1 aMcNeil, Andrew1 aLee, Eleanor, S. uhttps://facades.lbl.gov/publications/development-simulation-based-controls01207nas a2200121 4500008003900000245004800039210004600087260001200133490001500145520082500160100002200985856007801007 2012 d00aDiscomfort Glare: What Do We Actually Know?0 aDiscomfort Glare What Do We Actually Know c05/20120 vApril 20123 aGlare models were reviewed with an eye for missing conditions or inconsistencies. We found ambiguities as to when to use small source versus large source models, and as to what constitutes a glare source in a complex scene. We also found surprisingly little information validating the assumed independence of the factors driving glare.
A barrier to progress in glare research is the lack of a standardized dependent measure of glare. We inverted the glare models to predict luminance, and compared model predictions against the 1949 Luckiesh & Guth data that form the basis of many of them. The models perform surprisingly poorly, particularly with regards to the luminance-size relationship and additivity. Evaluating glare in complex scenes may require fundamental changes to form of the glare models.
1 aClear, Robert, D. uhttps://facades.lbl.gov/publications/discomfort-glare-what-do-we-actually01722nas a2200229 4500008003900000022001300039245013700052210006900189260001200258300001100270490000800281520098700289653001201276653001501288653002001303653001901323653002201342100001901364700001701383700001801400856007401418 2012 d a0021897900aDrifting localization of ionization runaway: Unraveling the nature of anomalous transport in high power impulse magnetron sputtering0 aDrifting localization of ionization runaway Unraveling the natur c03/2012 a0533040 v1113 aThe plasma over a magnetron’s erosion “racetrack” is not azimuthally uniform but concentrated in distinct dense ionization zones which move in the E x B direction with about 10% of the electron E x B/B2 drift velocity. The ionization zones are investigated with a gated camera working in concert with a streak camera for Al, Nb, Cu, and W targets in Ar or Kr background gas. It is found that each ionization zone has a high plasma density edge, which is the origin of a plasma-generating electron jet leaving the target zone. Each region of strong azimuthal plasma density gradient generates an azimuthal electric field, which promotes the escape of magnetized electrons and the formation of electron jets and plasma flares. The phenomena are proposed to be caused by an ionization instability where each dense plasma zone exhibits a high stopping power for drifting high energy electrons, thereby enhancing itself.
10aCameras10aionization10aMagnetic fields10aPlasma density10aplasma ionization1 aAnders, André1 aNi, Pavel, A1 aRauch, Albert uhttps://facades.lbl.gov/publications/drifting-localization-ionization01433nas 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 aLocalized 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-surface01087nas a2200157 4500008004100000245004000041210004000081260001200121300001200133490000700145520063800152100002200790700001900812700002100831856007700852 2009 eng d00aDaylight metrics and energy savings0 aDaylight metrics and energy savings c09/2009 a261-2830 v413 aThe drive towards sustainable, low-energy buildings has increased the need for simple, yet accurate methods to evaluate whether a "daylit" building meets minimum standards for energy and human comfort performance. Current metrics do not account for the temporal and spatial aspects of daylight, nor of occupants comfort or interventions. This paper reviews the historical basis of current compliance methods for achieving daylit buildings, proposes a technical basis for development of better metrics, and provides two case study examples to stimulate dialogue on how metrics can be applied in a practical, real-world context.
1 aMardaljevic, John1 aHeschong, Lisa1 aLee, Eleanor, S. uhttps://facades.lbl.gov/publications/daylight-metrics-and-energy-savings01603nas a2200121 4500008004100000050001400041245006300055210006300118260001200181520119200193100001901385856007701404 2008 eng d aLBNL-170E00aDeposition Rates of High Power Impulse Magneton Sputtering0 aDeposition Rates of High Power Impulse Magneton Sputtering c04/20083 aHigh power impulse magnetron sputtering (HIPIMS) is seen by many as the new paradigm in sputtering. It provides significant self-ion assistance to film growth. However, many noticed that deposition rates are reduced, often to less than 50%, compared to direct current (DC) sputtering rates at the same power input. It is argued here that the reduction is based on the physics of sputtering and self-sputtering, and it should not come as a surprise. Four effects can be distinguished (i) the yield effect caused by the less-than-linear increase of sputtering yield with ion energy, (ii) the impedance effect, influencing what fraction of the target-anode voltage drops in the sheath, (iii) the species effect associated with a change of ions causing sputtering, and (iv) the return effect associated with flux splitting in selfsputtering. The paper is completed by considering some business implications, in particular; it is argued that HIPIMS is a different technology and that its value should be judged comprehensively, not just by rates. Finally, the special case of temperature dependent sputtering is considered, which in some cases may lead to rates exceeding the DC rates.
1 aAnders, André uhttps://facades.lbl.gov/publications/deposition-rates-high-power-impulse02372nas a2200181 4500008004100000050001500041245012000056210006900176300001200245490000700257520173300264100002101997700002502018700002602043700002402069700002202093856007502115 2008 eng d aLBNL-1022E00aDeveloping Low-Conductance Window Frames: Capabilities and Limitations of Current Window Heat Transfer Design Tools0 aDeveloping LowConductance Window Frames Capabilities and Limitat a131-1530 v323 aWhile window frames typically represent 20-30% of the overall window area, their impact on the total window heat transfer rates may be much larger. This effect is even greater in low-conductance (highly insulating) windows which incorporate very low conductance glazings. Developing low-conductance window frames requires accurate simulation tools for product research and development. Based on a literature review and an evaluation of current methods of modeling heat transfer through window frames, we conclude that current procedures specified in ISO standards are not sufficiently adequate for accurately evaluating heat transfer through the low-conductance frames.
We conclude that the near-term priorities for improving the modeling of heat transfer through low-conductance frames are:
The technical energy-savings potential for smart integrated window-daylighting systems is excellent and can yield significant reductions in US commercial building energy use if adopted by a significant percentage of the market. However, conventional automated shades and daylighting controls have been commercially available for over two decades with less than 1-2% market penetration in the US. As with many innovations, the problem with accelerating market adoption is one of demonstrating real performance and decreasing risk and cost. The New York Times considered use of such daylighting systems for their new 139,426 m2 (1.5 Mft2) headquarters building in downtown Manhattan.
In the initial phase of work, The New York Times employed a unique approach to create a competitive marketplace for daylighting systems and to address their concerns about risk by building a full-scale daylighting mockup and evaluating commercially-available products. This field test formed the strategic cornerstone for accelerating an industry response to the building owners' challenge to a sleepy market. A procurement specification was produced and bids were received that met The Times cost-effective criteria. The Times decided to proceed with using these innovative systems in their new building.
This next phase of work consisted of two distinct tasks: 1) to develop and use commissioning tools and procedures to insure that the automated shade and daylighting control systems operate as intended prior to occupancy; and 2) to estimate the peak demand savings resulting from different levels of demand response (DR) control strategies (from moderate to severe load curtailment) and then determine the financial implications given various DR programs offered by the local utility and New York Independent System Operator in the area.
Commissioning daylighting control systems is mandatory to insure that design intent is met, that the systems are tuned to optimal performance, and to eliminate problems and errors before occupants move in. Commissioning tools were developed and procedures were defined and then used to verify that the daylighting systems operated according to the technical specifications. For both lighting control and shading systems, the Times and the manufacturers were able to resolve most of the bugs and fine-tune the systems prior to occupancy.
The demand response (DR) strategies at the New York Times building involve unique state-of-the-art systems with dimmable ballasts, movable shades on the glass facade, and underfloor air HVAC. The process to develop the demand response strategies, the results of the EnergyPlus model, the activities to implement the DR strategies in the controls design at the New York Times Headquarters building and the evaluation of economics of participating in DR programs are presented and discussed. The DR simulation iv efforts for this building design are novel, with an innovative building owner evaluating DR and future DR program participation strategies during the design and construction phase using advanced simulation tools.
10aautomated daylighting controls10aautomated window shades10adaylighting10ademand response10aenergy-efficiency10avisual comfort1 aLee, Eleanor, S.1 aHughes, Glenn, D.1 aClear, Robert, D.1 aFernandes, Luis, L.1 aKiliccote, Sila1 aPiette, Mary, Ann1 aRubinstein, Francis, M.1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/daylighting-new-york-times-002135nas a2200205 4500008004100000050001500041245005900056210005600115520147900171100002101650700002701671700002201698700002901720700002201749700002401771700002201795700002401817700002101841856006701862 2006 eng d aLBNL-5995000aA Design Guide for Early-Market Electrochromic Windows0 aDesign Guide for EarlyMarket Electrochromic Windows3 aSwitchable variable-tint electrochromic windows preserve the view out while modulating transmitted light, glare, and solar heat gains and can reduce energy use and peak demand. To provide designers objective information on the risks and benefits of this technology, this study offers data from simulations, laboratory tests, and a 2.5-year field test of prototype large-area electrochromic windows evaluated under outdoor sun and sky conditions. The study characterized the prototypes in terms of transmittance range, coloring uniformity, switching speed, and control accuracy. It also integrated the windows with a daylighting control system and then used sensors and algorithms to balance energy efficiency and visual comfort, demonstrating the importance of intelligent design and control strategies to provide the best performance. Compared to an efficient low-e window with the same daylighting control system, the electrochromic window showed annual peak cooling load reductions from control of solar heat gains of 19-26% and lighting energy use savings of 48-67% when controlled for visual comfort. Subjects strongly preferred the electrochromic window over the reference window, with preferences related to perceived reductions in glare, reflections on the computer monitor, and window luminance. The EC windows provide provided the benefit of greater access to view year-round. Though not definitive, findings can be of great value to building professionals.
1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E.1 aClear, Robert, D.1 aDiBartolomeo, Dennis, L.1 aKlems, Joseph, H.1 aFernandes, Luis, L.1 aWard, Gregory, J.1 aInkarojrit, Vorapat1 aYazdanian, Mehry uhttps://facades.lbl.gov/publications/design-guide-early-market01983nas a2200145 4500008004100000245012900041210006900170260003100239520140500270100002001675700002201695700002201717700002201739856007601761 2006 eng d00aDynamic Controls for Energy Efficiency and Demand Response: Framework Concepts and a New Construction Case Study in New York0 aDynamic Controls for Energy Efficiency and Demand Response Frame aPacific Grove, CAc06/20063 aMany of today's advanced building control systems are designed to improve granularity of control for energy efficiency. Examples include direct digital controls for building heating, ventilation, and cooling systems (HVAC), and dimmable ballasts for continuous dimming for daylighting applications. This paper discusses recent research on the use of new and existing controls in commercial buildings for integrated energy efficiency and demand response (DR). The paper discusses the use of DR controls strategies in commercial buildings and provides specific details on DR control strategy design concepts for a new building in New York. We present preliminary results from EnergyPlus simulations of the DR strategies at the New York Times Headquarters building currently under construction. The DR strategies at the Times building involve unique state of the art systems with dimmable ballasts, movable shades on the glass facade, and underfloor air HVAC. The simulation efforts at this building are novel, with an innovative building owner considering DR and future DR program participation strategies during the design phase. This paper also discusses commissioning plans for the DR strategies. The trends in integration of various systems through the EMCS, master versus supervisory controls and dynamic operational modes concepts are presented and future research directions are outlined.
1 aKiliccote, Sila1 aPiette, Mary, Ann1 aWatson, David, S.1 aHughes, Glenn, D. uhttps://facades.lbl.gov/publications/dynamic-controls-energy-efficiency02046nas a2200157 4500008004100000050001500041245010200056210006900158300001000227490000700237520148900244100002101733700002901754700002701783856007801810 2005 eng d aLBNL-5492400aDaylighting control performance of a thin-film ceramic electrochromic window: Field study results0 aDaylighting control performance of a thinfilm ceramic electrochr a30-440 v383 aControl system development and lighting energy monitoring of ceramic thin-film electrochromic (EC) windows were initiated at the new full-scale Window Systems testbed facility at the Lawrence Berkeley National Laboratory (LBNL) in Berkeley, California. The new facility consists of three identically configured side-by-side private offices with large-area windows that face due south. In one room, an array of EC windows with a center-of-glass visible transmittance (Tv) range of 0.05-0.60 was installed. In the two other rooms, unshaded windows with a Tv=0.50 or 0.15 were used as reference. The same dimmable fluorescent lighting system was used in all three rooms. This study explains the design and commissioning of an integrated EC window-lighting control system and then illustrates its performance in the testbed under clear, partly cloudy, and overcast sky conditions during the equinox period. The performance of an early prototype EC window controller is also analyzed. Lighting energy savings data are presented. Daily lighting energy savings were 44-59% compared to the reference window of Tv=0.15 and 8-23% compared to the reference window of Tv=0.50. The integrated window-lighting control system maintained interior illuminance levels to within ?10% of the setpoint range of 510-700 lux for 89-99% of the day. Further work is planned to refine the control algorithms and monitor cooling load, visual comfort, and human factor impacts of this emerging technology.
1 aLee, Eleanor, S.1 aDiBartolomeo, Dennis, L.1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/daylighting-control-performance-thin02657nas a2200265 4500008003900000245007100039210006900110260001200179520181700191653003502008653002802043653001602071653002202087653001902109100002102128700002702149700002202176700002202198700002202220700002202242700001402264700002102278700002402299856006802323 2005 d00aDaylighting the New York Times Headquarters Building: Final Report0 aDaylighting the New York Times Headquarters Building Final Repor c06/20053 aThe technical energy-savings potential for smart integrated window-daylighting systems is excellent and can yield significant reductions in US commercial building energy use if adopted by a significant percentage of the market. However, conventional automated shades and daylighting controls have been commercially available for over two decades with less than 1-2% market penetration in the US. As with all innovations, the problem with accelerating market adoption is one of decreasing risk. As the building owner researches technology options, the usual questions surface that concern the purchase of any new product: how will it work for my application, are the vendor claims valid, what risks are incurred, and will the performance benefits be sustained over the life of the installation? In their effort to create an environment that "enhances the way we work" in their new 139 km2 (1.5 Mft2) headquarters building in downtown Manhattan, The New York Times employed a unique approach to create a competitive marketplace for daylighting systems. A monitored field test formed the strategic cornerstone for accelerating an industry response to the building owners' challenge to a sleepy market (i.e., US automated shading and daylighting control products have had few major technical advances over the past 10 years). Energy, control system, and environmental quality performance of commercially-available automated roller shade and daylighting control systems were evaluated. Procurement specifications were produced. Bids were received that met The Times cost-effective criteria. The Times will proceed with the use of these systems in their final building. Competitively-priced new products have been developed as a result of this research and are now available on the market.
10aautomated daylighting controls10aautomated window shades10adaylighting10aenergy-efficiency10avisual comfort1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E.1 aHughes, Glenn, D.1 aClear, Robert, D.1 aWard, Gregory, J.1 aMardaljevic, John1 aLai, Judy1 aInanici, Mehlika1 aInkarojrit, Vorapat uhttps://facades.lbl.gov/publications/daylighting-new-york-times01061nas a2200133 4500008004100000050001500041245009100056210006900147260003000216520055200246100002500798700002600823856007800849 2005 eng d aLBNL-5753100aDElight2 Daylighting Analysis in Energy Plus: Integration and Preliminary User Results0 aDElight2 Daylighting Analysis in Energy Plus Integration and Pre aMontreal, Canadac08/20053 aDElight is a simulation engine for daylight and electric lighting system analysis in buildings. DElight calculates interior illuminance levels from daylight, and the subsequent contribution required from electric lighting to meet a desired interior illuminance. DElight has been specifically designed to integrate with building thermal simulation tools. This paper updates the DElight capability set, the status of integration into the simulation tool EnergyPlus, and describes a sample analysis of a simple model from the user perspective.
1 aCarroll, William, L.1 aHitchcock, Robert, J. uhttps://facades.lbl.gov/publications/delight2-daylighting-analysis-energy01246nas a2200169 4500008004100000050001500041245006200056210006100118260002500179520069000204100001900894700002000913700002700933700002500960700002200985856006901007 2004 eng d aLBNL-5551700aDevelopment of Trade-Off Equations for EnergyStar Windows0 aDevelopment of TradeOff Equations for EnergyStar Windows aBoulder, COc08/20043 aThe authors explore the feasibility of adding a performance option to DOE's EnergyStar© Windows program whereby windows of differing U-factors and SHGCs can qualify so long as they have equivalent annual energy performance. An iterative simulation procedure is used to calculate trade-off equations giving the change in SHGC needed to compensate for a change in U-factor. Of the four EnergyStar© Window climate zones, trade-off equations are possible only in the Northern and Southern zones. In the North/Central and South/Central zones, equations are not possible either because of large intrazone climate variations or the current SHGC requirements are already near optimum.
1 aHuang, Yu, Joe1 aMitchell, Robin1 aSelkowitz, Stephen, E.1 aArasteh, Dariush, K.1 aClear, Robert, D. uhttps://facades.lbl.gov/publications/development-trade-equations00811nam a2200241 4500008004100000050001500041245007900056210006900135100001600204700002300220700001900243700002500262700002000287700001700307700002000324700003000344700002000374700002100394700002000415700002800435700002700463856007900490 2001 eng d aLBNL-4749300aDaylight in Buildings. A Source Book on Daylighting Systems and Components0 aDaylight in Buildings A Source Book on Daylighting Systems and C1 aRuck, Nancy1 aAschehoug, Øyvind1 aAydinli, Sirri1 aChristoffersen, Jens1 aCourret, Gilles1 aEdmonds, Ian1 aJakobiak, Roman1 aKischkoweit-Lopin, Martin1 aKlinger, Martin1 aLee, Eleanor, S.1 aMichel, Laurent1 aScartezzini, Jean-Louis1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/daylight-buildings-source-book-daylighting-systems01238nas a2200169 4500008004100000050001500041245008000056210006900136260002700205520065300232100002500885700001900910700002000929700002200949700002200971856007500993 1999 eng d aLBNL-4402000aA Database of Window Annual Energy Use in Typical North American Residences0 aDatabase of Window Annual Energy Use in Typical North American R aDallas, Texasc02/20003 aThis paper documents efforts by the National Fenestration Rating Council to develop a database on annual energy impacts of windows in a typical new, single family, single story residence in various U.S. and Canadian climates. The result is a database of space heating and space cooling energies for 14 typical windows in 52 North American climates. (Future efforts will address the effects of skylights.) This paper describes how this database was created, documents the assumptions used in creating this database, elaborates on assumptions, which need further research, examines the results, and describes the possible uses of the database.
1 aArasteh, Dariush, K.1 aHuang, Yu, Joe1 aMitchell, Robin1 aClear, Robert, D.1 aKohler, Christian uhttps://facades.lbl.gov/publications/database-window-annual-energy-use01482nas a2200109 4500008004100000050001500041245006300056210006000119520109600179100002501275856007201300 1999 eng d aLBNL-4429600aDaylighting Simulation: Methods, Algorithms, and Resources0 aDaylighting Simulation Methods Algorithms and Resources3 aThe search for and collection of daylighting analysis methods and algorithms led to two important observations. First, there is a wide range of needs for different types of methods to produce a complete analysis tool. These include:
Second, very advantageously, there have been rapid advances in many basic methods in these areas, due to other forces. They are in part driven by:
This has led to a very rich set of information resources that have direct applicability to the small daylighting analysis community. Furthermore, much of this information is in fact available online.
1 aCarroll, William, L. uhttps://facades.lbl.gov/publications/daylighting-simulation-methods01728nas a2200145 4500008004100000050001500041245006900056210006800125260002200193300001200215520123200227100002101459700002701480856007501507 1997 eng d aLBNL-3972900aDesign and Performance of an Integrated Envelope/Lighting System0 aDesign and Performance of an Integrated EnvelopeLighting System aBath, UKc04/1997 a375-3803 aDynamic envelope/lighting systems offer the potential to achieve a near optimum energy-efficient environment meeting occupant needs throughout the year by adapting to dynamic meteorological conditions and changing occupant preferences in real time. With the dramatic increased functionality of the microprocessor, there is an untapped potential to make dynamic envelope/lighting systems easier to use, diagnose, and monitor, and to integrate them as part of a sophisticated building-wide control system. This study addresses the complex relationship between this energy-efficiency technology and many of the non-energy issues related to its potential acceptance by the building industry, architects, owners, and users. We demonstrate the concept of integrated dynamic systems with a prototype motorized venetian blind operated in synchronization with electric lighting and daylighting controls via an intelligent control system. Research work conducted with simulation software and reduced-scale and full-scale field tests is summarized. Much of this work is directly relevant to other active shading and daylighting systems on the market today and to state-of-the-art window systems yet to come (i.e., electrochromics).
1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/design-and-performance-integrated01361nas 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 aAs 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-redirecting02117nas a2200133 4500008004100000050001500041245007800056210006900134520162400203100003401827700002501861700002201886856007501908 1996 eng d aLBNL-4416700aDesign and Evaluation of Daylighting Applications of Holographic Glazings0 aDesign and Evaluation of Daylighting Applications of Holographic3 aWhen combined with appropriate electric lighting dimming controls, the use of daylight for ambient and task illumination can significantly reduce energy requirements in commercial buildings. While skylights can effectively illuminate any part of one-story buildings, conventional side windows can illuminate only a 15 ft - 20 ft (4.6 m - 6.1 m) depth of the building perimeter. Even so, the overall efficacy of daylight is limited, because side windows produce uneven distributions of daylight. Achieving adequate illumination at distances further away from the window results in excessive illumination near the window, which increases cooling loads from the associated solar heat gain. As a result, the use of larger apertures and/or higher transmittance glazings, to introduce daylight deeper than 15 ft - 20 ft (4.6 m - 6.1 m), may prove ineffective with respect to saving energy, because cooling load penalties may exceed the electric lighting savings.
The need for more uniform distribution of daylight admitted through side windows has stimulated significant research and development efforts in new fenestration designs and glazing technologies. Many of these approaches, including holographic glazings, rely on the common strategy of redirecting sunlight and reflecting it off the ceiling towards the back of the room. Prior studies on the daylight and energy performance of holographic glazings have been disappointing, however inconclusive because of poor hologram quality, low diffraction efficiency and inadequate hologram design and building application considerations [Papamichael et al 1994].
1 aPapamichael, Konstantinos, M.1 aEhrlich, Charles, K.1 aWard, Gregory, J. uhttps://facades.lbl.gov/publications/design-and-evaluation-daylighting01776nas a2200181 4500008004100000050001400041245008200055210006900137260001200206300001200218490000700230520117500237100002901412700002101441700002801462700002701490856007701517 1996 eng d aLBL-3813000aDeveloping a Dynamic Envelope/Lighting Control System with Field Measurements0 aDeveloping a Dynamic EnvelopeLighting Control System with Field c05/1996 a146-1640 v263 aThe feasibility of an intelligent venetian blind/lighting control system was tested in a 1:3 scale model outdoors under variable sun and sky conditions. The control algorithm, block direct sun and meet the design workplane illuminance level, was implemented using commercially available and custom designed blind and lighting systems hardware. While blocking direct sunlight, the blinds were properly controlled to maintain the design workplane illuminance within a tolerance of -10%, +25% when there was sufficient daylight. When daylight levels alone were inadequate, the electric lighting control system maintained the design workplane illuminance. The electric lighting could be turned off if a user-specified time period at minimum power was exceeded. Lighting energy savings of 51-71% (southwest) and 37-75% (south) was attained for the period from 8:00 to 17:00 on clear sunny days, compared to a fixed, partially closed blind with the same lighting system. Practical details for implementation and commissioning are discussed. The impact of control variations, such as profile angle, time step interval, and control area, on energy demand is investigated.
1 aDiBartolomeo, Dennis, L.1 aLee, Eleanor, S.1 aRubinstein, Francis, M.1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/developing-dynamic-envelopelighting02264nas a2200133 4500008004100000245011000041210006900151300001200220490000800232520176800240100002102008700002702029856007402056 1995 eng d00aThe Design and Evaluation of Integrated Envelope and Lighting Control Strategies for Commercial Buildings0 aDesign and Evaluation of Integrated Envelope and Lighting Contro a326-3420 v1013 aThis study investigates control strategies for coordinating the variable solar-optical properties of a dynamic building envelope system with a daylight controlled electric lighting system to reduce electricity consumption and increase comfort in the perimeter zone of commercial buildings. Control strategy design can be based on either simple, instantaneous measured data, or on complex, predictive algorithms that estimate the energy consumption for a selected operating state of the dynamic envelope and lighting system. The potential benefits of optimizing the operation of a dynamic envelope and lighting system are (1) significant reductions in electrical energy end-uses – lighting, and cooling due to solar and lighting heat gains – over that achieved by conventional static envelope and lighting systems, (2) significant reductions in peak demand, and (3) increased occupant visual and thermal comfort. The DOE-2 building energy simulation program was used to model two dynamic envelope and lighting systems, an automated venetian blind and an electrochromic glazing system, and their control strategies under a range of building conditions. The energy performance of simple control strategies are compared to the optimum performance of a theoretical envelope and lighting system to determine the maximum potential benefit of using more complex, predictive control algorithms. Results indicate that (1) predictive control algorithms may significantly increase the energy-efficiency of systems with non-optimal solar-optical properties such as the automated venetian blind, and (2) simpler, non-predictive control strategies may suffice for more advanced envelope systems incorporating spectrally selective, narrow-band electrochromic coatings.
1 aLee, Eleanor, S.1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/design-and-evaluation-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 aWe 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-advanced