@techreport {29804, title = {Technology Assessments of High Performance Envelope with Optimized Lighting, Solar Control, and Daylighting}, year = {2016}, month = {09/2016}, institution = {Lawrence Berkeley National Laboratory}, address = {Berkeley, CA}, abstract = {

Innovative, cost-effective, energy efficiency technologies and strategies for new and retrofit construction markets are essential for achieving near-term, broad market impacts. This study focuses on innovative shading and daylighting technologies that have the potential to significantly curtail annual cooling and lighting electricity use and reduce summer peak electric demand, particularly in the hot, sunny, inland areas where there has been significant population growth.

The building industry is well aware that energy-efficiency potential does not always match actual, real world performance in the field due to a variety of mitigating factors. Third party verification of the energy savings potential of innovative technologies is important for market adoption. In the case of shading and daylighting technologies, new simulation tools have only recently been developed to improve modeling accuracy. Market acceptance is also heavily dependent on how well the technology balances comfort and indoor environmental quality (IEQ) requirements (e.g., view, brightness, etc.). PG\&E commissioned this full-scale monitored study to better understand the impact of mitigating factors on performance so as to make more informed decisions when constructing program interventions that support technology adoption in the market.

}, author = {Eleanor S. Lee and Anothai Thanachareonkit and Samir Touzani and Spencer M. Dutton and Jordan Shackelford and Darryl J. Dickerhoff and Stephen E. Selkowitz} } @article {55580, title = {Monitored lighting energy savings from dimmable lighting controls in The New York Times Headquarters Building}, journal = {Energy and Buildings}, volume = {68}, year = {2014}, month = {01/2014}, pages = {498-514}, chapter = {498}, abstract = {

Digital addressable, dimmable lighting controls were introduced to the US market in the early 2000s with the promise of facilitating capture of potential energy savings with greater flexibility over their historic, typically unreliable, analog counterpart. The New York Times Company installed this emerging technology, after having tested the system thoroughly prior to procurement, in their new building in New York, New York. Four years after full occupancy in 2007, the owner agreed to participate in a post-occupancy monitored evaluation of the dimmable lighting system to verify actual performance in the field. Annual lighting energy savings from daylighting, setpoint tuning and occupancy controls were determined for the daylit, open-plan office areas on three typical floors (6, 11, and 20th floors) of the 51-story high-rise tower. Energy savings were calculated from ballast control signal and occupancy data recorded by the manufacturer{\textquoteright}s lighting control system. The ballast data were calibrated with independent measurements of lighting energy consumption. Savings from dimming controls (daylighting and setpoint tuning) were 12.6 kWh/m2-yr (1.17 kWh/ft2-yr) for the daylit spaces on the three floors overall, or 20\%, relative to ASHRAE 90.1-2007. Compared to the prescriptive code in effect at the time of the building{\textquoteright}s construction (ASHRAE 90.1-2001), savings were 21.0 kWh/m2-yr (1.95 kWh/ft2-yr) or 28\%. Annual lighting energy use with all lighting control strategies was 33.9 kWh/m2-yr (3.15 kWh/ft2-yr) in the daylit, open plan zones on average for the three floors. A simple payback analysis was conducted.

}, keywords = {Building energy-efficiency, daylighting, lighting control systems}, doi = {10.1016/j.enbuild.2013.10.009}, author = {Luis L. Fernandes and Eleanor S. Lee and Dennis L. DiBartolomeo and Andrew McNeil} } @techreport {60935, title = {A Pilot Demonstration of Electrochromic and Thermochromic Windows in the Denver Federal Center, Building 41, Denver, Colorado}, year = {2013}, note = {

Completed September 30, 2012, released March 30, 2014.

}, month = {07/2013}, abstract = {

Chromogenic glazing materials are emerging technologies that tint reversibly from a clear to dark tinted state either passively in response to environmental conditions or actively in response to a command from a switch or building automation system. Switchable coatings on glass manage solar radiation and visible light while enabling unobstructed views to the outdoors. Building energy simulations estimate that actively controlled, near-term chromogenic glazings can reduce perimeter zone heating, ventilation, and air- conditioning (HVAC) and lighting energy use by 10-20\% and reduce peak electricity demand by 20-30\%, achieving energy use levels that are lower than an opaque, insulated wall.

This project demonstrates the use of two types of chromogenic windows: thermochromic and electrochromic windows. By 2013, these windows will begin production in the U.S. by multiple vendors at high-volume manufacturing plants, enabling lower cost and larger area window products to be specified. Both technologies are in the late R\&D stage of development, where cost reductions and performance improvements are underway. Electrochromic windows have been installed in numerous buildings over the past four years, but monitored energy-efficiency performance has been independently evaluated in very limited applications. Thermochromic windows have been installed in one other building with an independent evaluation, but results have not yet been made public.

}, keywords = {building controls, daylighting, Demand Side Management, electrochromic, energy-efficiency, Smart windows, switchable windows, Thermochromic, Window}, url = {http://gsa.gov/portal/content/187967}, author = {Eleanor S. Lee and Luis L. Fernandes and Howdy Goudey and Jacob C. Jonsson and Dragan C. Curcija and Xiufeng Pang and Dennis L. DiBartolomeo and Sabine Hoffmann} } @techreport {3441, title = {A Post-Occupancy Monitored Evaluation of the Dimmable Lighting, Automated Shading, and Underfloor Air Distribution System in The New York Times Building}, year = {2013}, month = {01/2013}, institution = {Lawrence Berkeley National Laboratory}, address = {Berkeley, CA}, abstract = {

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

}, author = {Eleanor S. Lee and Luis L. Fernandes and Brian E. Coffey and Andrew McNeil and Robert D. Clear and Thomas L. Webster and Fred S. Bauman and Darryl J. Dickerhoff and David Heinzerling and Tyler Hoyt} } @article {58229, title = {Regional performance targets for transparent near-infrared switching electrochromic window glazings}, journal = {Building and Environment}, volume = {61}, year = {2013}, month = {03/2013}, pages = {160 - 168}, abstract = {

With building heating and cooling accounting for nearly 14\% of the national energy consumption, emerging technologies that improve building envelope performance have significant potential to reduce building energy consumption. Actual savings from these technologies will depend heavily upon their performance in diverse climate and operational conditions. In many cases, early-stage research can benefit from detailed investigation in order to develop performance thresholds and identify target markets. One example, a dynamic, highly transparent, near-infrared switching electrochromic (NEC) window glazing, is the focus of this investigation. Like conventional electrochromics, the NEC glazing can dynamically tune its optical properties with a small applied voltage. Consequently, the glazing can block or transmit solar heat to reduce cooling or heating loads, respectively. Unlike conventional electrochromics, NEC glazings remain transparent to visible light, causing no adverse effect to daylighting or building aesthetics. This study utilizes the software COMFEN to simulate a broad range of NEC performance levels, for commercial and residential buildings in 16 climate-representative reference cities. These simulations are the basis for identifying performance levels necessary to compete with existing static technologies. These results indicate that energy savings are strongly influenced by blocking-state performance. Additionally, residential applications have lower performance requirements due to their characteristic internal heat gains. Finally, the most dynamic NEC performance level is simulated in competition with high performing static alternatives. Here heating and cooling energy savings range from 5 to 11\ kWh/m2 yr for commercial and 8{\textendash}15\ kWh/m2 yr for residential, in many regions on the order of 10\%.

}, keywords = {Dynamic windows, Electrochromic glazings, NIR-switching, Performance targets, Solar heat gain}, issn = {03601323}, doi = {10.1016/j.buildenv.2012.12.004}, author = {Nicholas DeForest and Arman Shehabi and Guillermo Garcia and Jeffery B. Greenblatt and Eric R. Masanet and Eleanor S. Lee and Stephen E. Selkowitz and Delia J. Milliron} } @article {57807, title = {U.S. energy savings potential from dynamic daylighting control glazings}, journal = {Energy and Buildings}, volume = {66}, year = {2013}, month = {11/2013}, pages = {415-423}, chapter = {415}, abstract = {

Daylighting controls have the potential to reduce the substantial amount of electricity consumed for lighting in commercial buildings. Material science research is now pursuing the development of a dynamic prismatic optical element (dPOE) window coating that can continuously readjust incoming light to maximize the performance and energy savings available from daylighting controls. This study estimates the technical potential for energy savings available from vertical daylighting strategies and explores additional savings that may be available if current dPOE research culminates in a successful market-ready product. Radiance daylight simulations are conducted with a multi-shape prismatic window coating. Simulated lighting energy savings are then applied to perimeter floorspace estimates generated from U.S. commercial building stock data. Results indicate that fully functional dPOE coatings, when paired with conventional vertical daylight strategies, have the potential to reduce energy use associated with U.S. commercial electric lighting demand by as much as 930 TBtu. This reduction in electric lighting demand represents an approximately 85\% increase in the energy savings estimated from implementing conventional vertical daylight strategies alone. Results presented in this study provide insight into energy and cost performance targets for dPOE coatings, which can help accelerate the development process and establish a successful new daylighting technology.

}, keywords = {Clerestories, daylighting, Dynamic prismatic optical elements (dPOE), energy efficiency, Glare, indoor environmental quality, radiance, windows}, doi = {10.1016/j.enbuild.2013.07.013}, author = {Arman Shehabi and Nicholas DeForest and Andrew McNeil and Eric R. Masanet and Jeffery B. Greenblatt and Eleanor S. Lee and Georgeta Masson and Brett A. Helms and Delia J. Milliron} } @conference {57409, title = {Application of a stochastic window use model in EnergyPlus}, booktitle = {SimBuild 2012, 5th National Conference of IBPSA-USA, August 1-3, 2012}, year = {2012}, month = {08/2012}, address = {Madison, WI}, abstract = {

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

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

}, url = {https://escholarship.org/uc/item/2gm7r783}, author = {Spencer M. Dutton and Hui Zhang and Yongchao Zhai and Edward A. Arens and Youness Bennani Smires and Samuel L. Brunswick and Kyle S. Konis and Philip Haves} } @conference {58301, title = {Co-simulation based building controls implementation with networked sensors and actuators}, booktitle = {Third ACM Workshop on Embedded Sensing Systems for Energy-Efficiency in Buildings}, volume = {Proceedings of BuildSys 2011}, year = {2011}, month = {11/2011}, pages = {55}, publisher = {ACM Press}, organization = {ACM Press}, address = {Seattle, Washington}, abstract = {

The commercial building sector is one of the largest energy consumers in the U.S., and lighting, heating, ventilating and air conditioning contribute to more than half of the energy consumption and carbon emissions in buildings. Controls are the most effective way of increasing energy efficiency in building systems; however, the interdependencies among building subsystems must be taken into account to achieve deep energy savings. A networked sensing and actuation infrastructure shared among building systems is the key to optimal integrated control of the interdependent building elements in low energy and zero net energy buildings.

This paper presents a rapid-prototyping controls implementation platform based on the Building Controls Virtual Test Bed (BCVTB) framework that is capable of linking to building sensor and actuator networks for efficient controller design and testing. The platform creates a separation between the controls and the physical systems so that the controller can easily be implemented, tested and tuned with real performance feedback from a physical implementation. We realized an integrated lighting control algorithm using such a rapid-prototyping platform in a testing facility with networked sensors and actuators. This implementation has demonstrated an up to 57\% savings in lighting electricity and 28\% reduction in cooling demand.

}, isbn = {9781450307499}, doi = {10.1145/2434020.2434040}, author = {Yao-Jung Wen and Dennis L. DiBartolomeo and Francis M. Rubinstein} } @article {58228, title = {Field Measurements of Innovative Indoor Shading Systems in a Full-Scale Office Testbed}, journal = {ASHRAE Transactions}, volume = {115}, year = {2009}, month = {10/2009}, pages = {706-728}, chapter = {706}, abstract = {

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 fa{\c c}ade 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.

}, author = {Eleanor S. Lee and Dennis L. DiBartolomeo and Joseph H. Klems and Robert D. Clear and Kyle S. Konis and Mehry Yazdanian and Byoung-Chul Park} } @techreport {1458, title = {High Performance Building Facade Solutions: PIER Final Project Report}, year = {2009}, month = {12/2009}, abstract = {

Building fa{\c c}ades 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. fa{\c c}ades 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, fa{\c c}ade 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 fa{\c c}ades industry to develop, evaluate, and accelerate market deployment of emerging, high-performance, integrated fa{\c c}ade 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 fa{\c c}ade-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 fa{\c c}ade 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 fa{\c c}ade 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.

}, author = {Eleanor S. Lee and Stephen E. Selkowitz and Dennis L. DiBartolomeo and Joseph H. Klems and Robert D. Clear and Kyle S. Konis and Robert J. Hitchcock and Mehry Yazdanian and Robin Mitchell and Maria Konstantoglou} } @article {58915, title = {Innovative Fa{\c c}ade Systems for Low-energy Commercial Buildings}, year = {2009}, month = {11/2009}, publisher = {Lawrence Berkeley National Laboratory}, address = {Berkeley}, abstract = {

Glazing and fa{\c c}ade 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.

Fa{\c c}ade designs that deliberately recognize the fundamental synergistic relationships between the fa{\c c}ade, lighting, and mechanical systems have the potential to deliver high performance over the life of the building. These "integrated" fa{\c c}ade 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 {\textemdash} technology concepts, measured data, case study information, simulation tools, etc. {\textemdash} can enable architects and engineers to define integrated fa{\c c}ade 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.

}, author = {Eleanor S. Lee and Stephen E. Selkowitz and Dennis L. DiBartolomeo and Joseph H. Klems and Robert D. Clear and Kyle S. Konis and Maria Konstantoglou and Mark Perepelitza} } @conference {1420, title = {Field Evaluation of Low-E Storm Windows}, booktitle = {Thermal Performance of the Exterior Envelopes of Whole Buildings X International Conference}, volume = {277}, year = {2007}, month = {12/2007}, pages = {228-236}, address = {Clearwater Beach, FL}, abstract = {

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

}, author = {S. Craig Drumheller and Christian Kohler and Stefanie Minen} } @conference {1935, title = {Two-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer in Horizontal Window Frames with Internal Cavities}, booktitle = {2007 ASHRAE Winter Meeting}, year = {2007}, month = {01/2007}, address = {Dallas, TX}, abstract = {

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

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

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

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

}, author = {Arlid Gustavsen and Christian Kohler and Arvid Dalehaug and Dariush K. Arasteh} } @techreport {1077, title = {Advancement of Electrochromic Windows}, year = {2006}, month = {04/2006}, abstract = {

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{\textquoteright}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.

}, keywords = {commercial buildings, daylight, daylighting controls, Electrochromic windows, energy efficiency, human factors, peak demand, switchable windows, visual comfort}, author = {Eleanor S. Lee and Stephen E. Selkowitz and Robert D. Clear and Dennis L. DiBartolomeo and Joseph H. Klems and Luis L. Fernandes and Gregory J. Ward and Vorapat Inkarojrit and Mehry Yazdanian} } @techreport {1264, title = {A Design Guide for Early-Market Electrochromic Windows}, year = {2006}, abstract = {

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.

}, author = {Eleanor S. Lee and Stephen E. Selkowitz and Robert D. Clear and Dennis L. DiBartolomeo and Joseph H. Klems and Luis L. Fernandes and Gregory J. Ward and Vorapat Inkarojrit and Mehry Yazdanian} } @techreport {58258, title = {Experimental Validation of Daylighting Simulation Methods for Complex Fenestration Systems}, year = {2006}, month = {05/2006}, abstract = {

The objective of this paper is to assess the capability of existing lighting simulation methods to predict the performance of complex fenestration systems, which are becoming a commonly used component in buildings construction domain. A specific experimental protocol was conducted to collect reliable reference data based on illuminance measurements inside a black box with (and without) one complex glazing sample facing a measured external luminance distribution. Two types of simulation methods were tested and compared: The first is based on modeling the glazing sample in a ray-tracing simulation program and the second is based on use of the samples{\textquoteright} BTDF data. The BTDF data sets were combined with the external luminance distribution to predict the flux distribution inside the room and the resulting illuminance values at the reference points. The comparison between the experimental reference data and the simulation results showed that the influence of the CFS could be predicted with good accuracy.

}, author = {Fawaz Maamari and Marilyn Andersen and Jan de Boer and William L. Carroll and Dominique Dumortier and Phillip Greenup} } @conference {12088, title = {Monitored Energy Performance of Electrochromic Windows Controlled for Daylight and Visual Comfort}, booktitle = {2006 ASHRAE Annual Meeting}, volume = {112 Issue 2}, year = {2006}, month = {10/2006}, address = {Quebec City, Canada}, abstract = {

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.

}, keywords = {building automation and controls, Building envelope, commercial buildings}, author = {Eleanor S. Lee and Dennis L. DiBartolomeo and Joseph H. Klems and Mehry Yazdanian and Stephen E. Selkowitz} } @article {11682, title = {Daylighting control performance of a thin-film ceramic electrochromic window: Field study results}, journal = {Energy and Buildings}, volume = {38}, number = {4}, year = {2005}, pages = {30-44}, abstract = {

Control 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.

}, author = {Eleanor S. Lee and Dennis L. DiBartolomeo and Stephen E. Selkowitz} } @article {12036, title = {Low-Cost Networking for Dynamic Window Systems}, journal = {Energy and Buildings}, volume = {36}, number = {6}, year = {2004}, pages = {503-513}, abstract = {

A low-cost building communications network is needed that would allow individual window and lighting loads to be controlled fromsan existing enterprise LAN network. This building communications network concept, which we term Integrated Building EnvironmentalsCommunications System (IBECSTM), would enable both occupant-based and building-wide control of individual window, lighting, andssensor devices. IBECS can reduce the cost of systemic control because it allows a drastic cost reduction in per point networking costs. This kind of effort is needed to encourage the control industry to make the commitment to build this technology and to demonstratesto prospective customers that this breakthrough approach to more comprehensive systemic control will provide them with high-quality,sconvenient control while saving them money.

The development and demonstration of network interfaces to DC- and AC-motorized shades and to an electrochromic window aresdescribed. The network interfaces enable one to control and monitor the condition of these fenestration appliances from a variety of sources,sincluding a user?s personal computer. By creating a functional specification for an IBECS network interface and testing a prototype, thesability to construct such an interface was demonstrated and the cost-effective price per point better understood. The network interfacesswere demonstrated to be reliable in a full-scale test of three DC-motorized Venetian blinds in an open-plan office over 2 years and in limitedsbench-scale tests of an electrochromic window.

}, author = {Eleanor S. Lee and Dennis L. DiBartolomeo and Francis M. Rubinstein and Stephen E. Selkowitz} } @article {30021, title = {Application issues for large-area electrochromic windows in commercial buildings}, journal = {Solar Energy Materials and Solar Cells}, volume = {71}, year = {2002}, month = {03/2002}, pages = {465{\textendash}491}, abstract = {

Projections of performance from small-area devices to large-area windows and enterprise marketing have created high expectations for electrochromic glazings. As a result, this paper seeks to precipitate an objective dialog between material scientists and building-application scientists to determine whether actual large-area electrochromic devices will result in significant performance benefits and what material improvements are needed, if any, to make electrochromics more practical for commercial building applications. Few in situ tests have been conducted with large-area electrochromic windows applied in buildings. This study presents monitored results from a full-scale field test of large-area electrochromic windows to illustrate how this technology will perform in commercial buildings. The visible transmittance (T v ) of the installed electrochromic ranged from 0.11 to 0.38. The data are limited to the winter period for a south-east-facing window. The effect of actual device performance on lighting energy use, direct sun control, discomfort glare, and interior illumination is discussed. No mechanical system loads were monitored. These data demonstrate the use of electrochromics in a moderate climate and focus on the most restrictive visual task: computer use in offices. Through this small demonstration, we were able to determine that electrochromic windows can indeed provide unmitigated transparent views and a level of dynamic illumination control never before seen in architectural glazing materials. Daily lighting energy use was 6-24\% less compared to the 11\%-glazing, with improved interior brightness levels. Daily lighting energy use was 3\% less to 13\% more compared to the 38\%-glazing, with improved window brightness control. The electrochromic window may not be able to fulfill both energy-efficiency and visual comfort objectives when low winter direct sun is present, particularly for computer tasks using cathode-ray tube (CRT) displays. However, window and architectural design as well as electrochromic control options are suggested as methods to broaden the applicability of electrochromics for commercial buildings. Without further modification, its applicability is expected to be limited during cold winter periods due to its slow switching speed. {\textcopyright} 2002 Elsevier Science B.V. All rights reserved.

}, issn = {0927-0248}, doi = {10.1016/S0927-0248(01)00101-5}, author = {Eleanor S. Lee and Dennis L. DiBartolomeo} } @techreport {1159, title = {A Characterization of the Nonresidential Fenestration Market}, year = {2002}, abstract = {

The purpose of this report is to characterize the nonresidential fenestration market in order to better understand market barriers to, and opportunities for, energy-efficient fenestration products. In particular, the goal is to:

The U.S. glass industry is a $27 billion enterprise with both large producers and small firms playing pivotal roles in the industry. While most sectors of the glass industry have restructured and consolidated in the past 20 years, the industry still employs 150,000 workers. Nonresidential glazing accounts for approximately 18\% of overall U.S. glass production. In 1999, nonresidential glazing was supplied to approximately 2.2 billion ft2 of new construction and additions. That same year, nonresidential glazing was also supplied to approximately 1.1 billion ft2 of remodeling construction. With an industry this large and complex, it is to be expected that many market participants can influence fenestration selection. If market barriers to the selection of high performance fenestration products are better understood, then the U. S. Department of Energy (USDOE), the Northwest Energy Efficiency Alliance (NEEA), and others can develop programs and policies that promote greater energy efficiency in commercial glazing products.

}, author = {Arman Shehabi and Charles N. Eley and Dariush K. Arasteh and Phil Degens} } @conference {11791, title = {Electrochromic Windows for Commercial Buildings: Monitored Results from a Full-Scale Testbed}, booktitle = {ACEEE 2000 Summer Study on Energy Efficiency in Buildings, Efficiency and Sustainability, August 20-25, 2000}, year = {2000}, month = {04/2000}, address = {Pacific Grove, CA}, abstract = {

Electrochromic glazings promise to be the next major advance in energy-efficient window technology, helping to transform windows and skylights from an energy liability to an energy source for the nations building stock. Monitored results from a full-scale demonstration of large-area electrochromic windows are given. The test consisted of two side-by-side, 3.7x4.6 m, office-like rooms. In each room, five 62x173-cm lower electrochromic windows and five 62x43-cm upper electrochromic windows formed a large window wall. The window-to-exterior wall ratio (WWR) was 0.40. The southeast-facing electrochromic windows had an overall visible transmittance (Tv) range of Tv =0.11-0.38 and were integrated with a dimmable electric lighting system to provide constant work plane illuminance and to control direct sun.

Daily lighting use from the automated electrochromic window system decreased by 6 to 24\% compared to energy use with static, low-transmission (Tv =0.11), unshaded windows in overcast to clear sky winter conditions in Oakland, California. Daily lighting energy use increased as much as 13\% compared to lighting energy use with static windows that had Tv =0.38. Even when lighting energy savings were not obtainable, the visual environment produced by the electrochromic windows, indicated by well-controlled window and room luminance levels, was significantly improved for computer-type tasks throughout the day compared to the visual environment with unshaded 38\%-glazing. Cooling loads were not measured, but previous building energy simulations indicate that additional savings could be achieved. To ensure visual and thermal comfort, electrochromics require occasional use of interior or exterior shading systems when direct sun is present. Other recommendations to improve electrochromic materials and controls are noted along with some architectural constraints.

}, author = {Eleanor S. Lee and Dennis L. DiBartolomeo and Stephen E. Selkowitz} } @article {12213, title = {Refractive Index Changes of Pd-Coated Magnesium Ianthanide Switchable Mirrors Upon Hydrogen Insertion}, journal = {Journal of Applied Physics}, volume = {85}, number = {1}, year = {1999}, month = {01/1999}, pages = {408-413}, chapter = {408}, abstract = {

The optical effect upon insertion of hydrogen into Pd-coated magnesium lanthanide switchable mirrors is investigated in terms of the changes of their complex refractive indices. A significant change in the optical constants of LnMg layers is seen between the as-deposited state and the dehydrided state after one cycle. Furthermore, the optical effect of switching the Pd cap layer to a PdH cap layer was determined. It is shown that the Pd layer mainly limits the visible transmittance of the hydrided stack to about 35\%-40\%. Whereas the extinction coefficient of dehydrided LnMg layers at 550 nm is between 2.2 and 3.1, it is as low 10-4 as in the transparent state. This is of great promise to applications requiring large optical contrast (e.g., optical switches).

}, issn = {0021-8979 }, doi = {10.1063/1.369399}, author = {Klaus von Rottkay and Michael D. Rubin and Peter A. Duine} } @article {11766, title = {Effect of Hydrogen Insertion on the Optical Properties of PD-Coated Magnesium Lanthanides}, journal = {Electrochimica Acta}, year = {1998}, month = {9/1998}, address = {London, U.K.}, abstract = {

Metallic magnesium lanthanide thin films upon insertion of hydrogen transform to a highly transparent hydride phase. With a Pd overlayer, the transformation can be produced either by electrochemical insertion of hydrogen or by exposing the film to hydrogen gas. Unlike amorphous oxide electrochromics, the transformation is accompanied by a large change in visible reflectance (about 50\%). The optical switching effect in these materials is investigated in terms of changes in the complex refractive index as determined by variable-angle spectroscopic ellipsometric and normal-incidence radiometric measurements over the solar spectrum. Furthermore the optical effect of converting the Pd caplayer to Pd-H was determined. It is shown that the pd layer limits the visible transmittance of the hyrdrided stack to about 35-40\%. Whereas the extinction coefficient of the dehydrided LnMg-layers at 550 nm is between 2.2 and 3.1, it is as low as 10-4 in the transparent state.

}, author = {Klaus von Rottkay and Michael D. Rubin and Franck Michalak and Robert D. Armitage and Thomas J. Richardson and Jonathan L. Slack and Peter A. Duine} } @article {11774, title = {The Effect of Venetian Blinds on Daylight Photoelectric Control Performance}, journal = {Journal of the Illuminating Engineering Society}, volume = {28}, number = {1}, year = {1998}, abstract = {

We investigate how a venetian blind, a common but optically complex fenestration system, contributes to the unreliable performance of daylighting control systems. Using a fully instrumented, full-scale testbed facility, we monitored the daylighting performance of a modified closed-loop proportional photoelectric control system in a private office over the course of a year. The ratio of workplane illuminance from daylight to photosensor signal is characterized in terms of solar condition and venetian blind angle. Variations in this ratio causes actual illuminance levels to be periodically insufficient. This type of characterization can be used by the installer to determine whether the initial control adjustments made during commissioning will lead to reliable performance under most daylight conditions. Commissioning guidelines are given with caution, based on our observations from this specific case study.

We quantified the effect of variability in this ratio on control performance. With a middle-of-the-road gain constant, monitored workplane illuminance levels did not fall below 90\% of the design setpoint for 91\% of the year. When discrepancies occurred, differences between the daylight correlation and measured conditions were the primary cause of insufficient illuminance at the workplane. This performance is not applicable to commercially-available closed-loop proportional systems because 1) typical systems are rarely commissioned properly upon installation, and 2) off-the-shelf systems combine the photosensor{\textquoteright}s response to daylight and electric light into one gain parameter. Even though the prototype system was subject to the same discrepancies in the daylight correlation fit as commercially-available systems, performance was substantially improved because the prototype was able to separate the electric lighting contribution to workplane illuminance from the daylighting contribution, at no added cost. Commissioning should accommodate the effect of the fenestration system, since variations in luminance distributions produced by the window are the primary cause of unreliable performance.

}, author = {Eleanor S. Lee and Dennis L. DiBartolomeo and Stephen E. Selkowitz} } @conference {2929, title = {Integrated Performance of an Automated Venetian Blind/Electric Lighting System in a Full-Scale Private Office}, booktitle = {ASHRAE/DOE/BTECC Conference, Thermal Performance of the Exterior Envelopes of Buildings VII}, year = {1998}, month = {09/1998}, address = {Clearwater Beach, FL}, abstract = {

Comprehensive results are presented from a full-scale testbed of a prototype automated venetian blind/lighting system installed in two unoccupied, private offices in Oakland, California. The dynamic system balanced daylight against solar heat gains in real-time, to reduce perimeter zone energy use and to increase comfort. This limited proof-of-concept test was designed to work out practical "bugs" and refine design details to increase cost effectiveness and acceptability of this innovative technology for real-world applications. We present results from 14 months of tuning the system design and monitoring energy performance and control system operations. For this southeast-facing office, we found that 1-22\% lighting energy savings, 13-28\% cooling load reductions, and 13-28\% peak cooling load reductions can be achieved by the dynamic system under clear sky and overcast conditions year round, compared to a static, partly closed blind with the same optimized daylighting control system. These energy savings increase if compared to conventional daylighting controls with manually-operated blinds. Monitored data indicated that the control system met design objectives under all weather conditions to within 10\% for at least 90\% of the year. A pilot human factors study indicated that some of our default control settings should be adjusted to increase user satisfaction. With these adjustments, energy savings will decrease. The final prototype design yielded a 10-year simple payback for this site. If mechanical system downsizing opportunities and qualitative improvements to worker{\textquoteright}s comfort are included, this innovative technology could be more cost effective. Marketing information for commercializing this technology is given.

}, author = {Eleanor S. Lee and Dennis L. DiBartolomeo and Edward L. Vine and Stephen E. Selkowitz} } @article {1675, title = {Office Worker Response to an Automated Venetian Blind and Electric Lighting System: A Pilot Study}, journal = {Energy and Buildings}, volume = {28}, year = {1998}, month = {10/1998}, pages = {205-218}, chapter = {205}, abstract = {

A prototype integrated, dynamic building envelope and lighting system designed to optimize daylight admission and solar heat gain rejection on a real-time basis in a commercial office building is evaluated. Office worker response to the system and occupant-based modifications to the control system are investigated to determine if the design and operation of the prototype system can be improved. Key findings from the study are: (1) the prototype integrated envelope and lighting system is ready for field testing, (2) most office workers (N=14) were satisfied with the system, and (3) there were few complaints. Additional studies are needed to explain how illuminance distribution, lighting quality, and room design can affect workplane illuminance preferences.

}, keywords = {behavior, Comfort, commercial buildings, daylighting, envelope}, doi = {10.1016/S0378-7788(98)00023-1}, author = {Edward L. Vine and Eleanor S. Lee and Robert D. Clear and Dennis L. DiBartolomeo and Stephen E. Selkowitz} } @article {2867, title = {Thermal and Daylighting of an Automated Venetian Blind and Lighting System in a Full-Scale Private Office}, journal = {Energy and Buildings}, volume = {29}, number = {1}, year = {1997}, month = {07/01/1997}, pages = {47-63}, abstract = {

Dynamic envelope/lighting systems have the potential to optimize the perimeter zone energy balance between daylight admission and solar heat gain rejection on a real-time basis, and to increase occupant comfort. Two side-by-side full-scale offices in Oakland, California were built to further develop and test this concept. An automated venetian blind was operated in synchronization with a dimmable electric lighting system to block direct sun, provide the design workplane illuminance, and maximize view. The research program encompassed system design refinements, energy measurements, and human factors tests. In this study, we present lighting energy and cooling load data that were monitored in this facility over the course of a year. Significant energy savings and peak demand reductions were attained with the automated venetian blind/ lighting system compared to a static venetian blind with the same dimmable electric lighting system. Correlations between key weather parameters and cooling and lighting were used to illustrate how the dynamic system was able to simultaneously achieve optimization between lighting and cooling end uses under the full range of weather conditions of this sunny, moderate climate. Energy-efficiency estimates were conservative since experience shows that conventional daylighting control systems and manually operated shading devices are rarely used effectively in real world applications.

}, author = {Eleanor S. Lee and Dennis L. DiBartolomeo and Stephen E. Selkowitz} } @article {2850, title = {Developing a Dynamic Envelope/Lighting Control System with Field Measurements}, journal = {Journal of the Illuminating Engineering Society}, volume = {26}, number = {1}, year = {1996}, month = {05/1996}, pages = {146-164}, abstract = {

The 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.

}, author = {Dennis L. DiBartolomeo and Eleanor S. Lee and Francis M. Rubinstein and Stephen E. Selkowitz} } @article {1849, title = {Strain Related Phenomena in GaN Thin Films}, journal = {Physical Review B}, volume = {54}, number = {24}, year = {1996}, month = {12/1996}, pages = {17745-17753}, chapter = {17745}, abstract = {

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

}, doi = {10.1103/PhysRevB.54.17745}, author = {Christian F. Kisielowski and Joachim Kr{\"u}ger and Sergei Ruvimov and Tadeusz Suski and Joel W. Ager III and Erin C. Jones and Zuzanna Liliental-Weber and Michael D. Rubin and Eicke R. Weber and Michael D. Bremser and Robert F. Davis}, editor = {Joachim Kr{\"u}ger} } @conference {12141, title = {Optical and Electrochemical Properties of Sol-gel Spin Coated CeO2-TiO2 Films}, booktitle = {SPIE Meeting}, year = {1995}, month = {07/1995}, address = {San Diego, CA}, abstract = {

The optical and electrochemical properties of sol-gel spin coated Ce02-TiO2 (50\% CeO2) films were investigated for electrochrornic applications. The coating solutions were prepared by using mixed organic-inorganic | Ti(OC2H5)4 and Ce(NH4)2 (NO3)6 | precursors. X-ray diffraction studies showed the sol-gel spin-coated films were composed of an amorphous matrix of titanium oxide containing nanocrystallites of cerium oxide. The coating solar transmission value was Ts=0.8 (250 nm thick). The refractive index and the extinction coefficient were derived from transmittance measurements in the UV-VIS-NIR regions. These films had refractive index value of n=2.18 and extinction coefficient value of k=8x10-4 at λ=550 nm. Cyclic voltametric measurements showed reversible electrochemical insertion of lithium ions in a CeO2-TiO2/LiClO4-propylene carbonate electrochemical cell. During cycling the films maintain high optical transmittance. Spectrophotometric and electrochemical investigations performed on CeO2-TiO2 films revealed that these films are suitable as an optically passive counter-electrode in lithium electrochromic devices.

}, keywords = {cerium oxide-titanium oxide, counter electrode, electrochemical properties, electrochromic device, optical properties, sol-gel deposition}, author = {Nilg{\"u}n {\"O}zer and Selmar DeSouza and Carl M Lampert} } @conference {11643, title = {A Comprehensive Approach to Integrated Envelope and Lighting Systems for New Commercial Buildings}, booktitle = {ACEEE 1994 Summer Study on Energy Efficiency in Buildings}, year = {1994}, month = {09/1994}, address = {Pacific Grove, CA}, abstract = {

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.

}, author = {Eleanor S. Lee and Stephen E. Selkowitz and Francis M. Rubinstein and Joseph H. Klems and Liliana O. Beltran and Dennis L. DiBartolomeo} } @conference {11610, title = {Characteristics of Laminated Electrochromic Devices Using Polyorganodisulfate Electrodes}, booktitle = {SPIE Proceedings 2017}, year = {1993}, pages = {143}, abstract = {

The use of polyorganodisulfides as optically passive counterelectrodes in a variety of electrochromic devices are discussed. Characteristic data is presented for electrochmmic devices using proton, and lithium coloration ions with polyethylene oxide electrolyte and polydimercaptothiadiazole positive electrodes. Solid state devices consisting of molybdenum doped W03, amorphous polyethylene oxide electrolyte (a-PEO), and a polyorganodisulfide counter-electrode colored rapidly from a pale yellow to a deep blue-green, upon application of 1.2 V d.c. The photopic transmittance changed from 61 to 98, and the solar transmittance from 45 to 5\% during the coloration process. Also, our experiments with polyimidazole are detailed. This family of compounds due to its unique electrical and ion conduction properties allow a single composite ion storage and ion conductor electrode to be made, simplifying the device construction. Devices rnade from this family of compounds color to deep blue-gray upon application of 1.2-1.5 V. Bleaching occurs at -0.4 to -0.5 s. The photopic transmittance changed from 55 to 9\%. and the solar transmittance from 34 to 4\% during coloration. Both coloration and bleaching are quite rapid.

}, author = {Carl M Lampert and Steven J. Visco and Marca M. Doeff and Yan Ping Ma and Yongxiang He and Jean-Christophe Giron} } @article {12175, title = {Phase I Results of the NFRC U-Value Procedure Validation Project}, journal = {ASHRAE Transactions}, volume = {100, Pt. 1}, number = {Part 1}, year = {1993}, month = {08/1993}, abstract = {

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

}, author = {Dariush K. Arasteh and Fredric A. Beck and Nehemiah Stone and William DuPont and R. Christophe Mathis and Michael Koenig} }