Konstantinos Papamichael

• Professor Emeritus at University of California, Davis

Adaptive lighting refers to electric lighting sources that automatically adjust their output based on environmental changes, aiming at maximizing comfort, wellbeing and energy efficiency. This presentation provides an overview of the concept, focusing on adaptive lighting controls based on sensing occupancy and daylight. The overview reflects the a...

The economic efficiency of building core sunlighting systems (BCSS) that are used to deliver sunlight into building core is essential for their widespread use. This study analyses the costs and benefits of using the BCSS through a parametric evaluation process considering key parameters, such as installed and saved lighting power, electricity costs...

We report on the potential of today's LED technologies to approximate Spectral Power Distributions (SPDs) aimed at optimizing specific performance goals. We compare numerically optimal SPDs to actual SPDs produced by a 16-channel LED light source, aiming at optimizing performance for six different applications. These theoretical and practical limit...

For many people, the correct perception of the colors of objects is an important part of life, and today it is being threatened by misinformed policy-making and associated business decisions.Some conservationists and lamp manufacturers have concluded that the accurate color rendering provided by ordinary incandescent lamps is an unaffordable luxury...

The Energy Star Program Requirements for Televisions Version 5 test procedures for Automatic Brightness Control (ABC) enabled televisions' required power measurements at 0 Lux and 300 Lux of ambient light incident on the television screen. In 2010 the Collaborative Labeling and Appliance Standards Program (CLASP) funded a study to assess how accura...

Networked luminaires using occupancy sensors can ratchet up the energy savings for roadway lighting

On a worldwide scale lighting accounts for 20% to 50% of buildings’ energy use and 19% of the global electricity consumption, and therefore represents a key opportunity for energy efficiency efforts in different countries due to its relevant impact and often short payback periods of investments. Among the various strategies developed to foster effi...

A strategic approach that avoids the pitfalls of the CFL launch will be needed if LED replacement lamps are to dislodge incandescents in residential applications

The California Lighting Technology Center (CLTC) is demonstrating and evaluating various smart corridor technologies in the laboratory and in the field. The evaluations focus on energy savings, demand-response effectiveness, and occupant response, while continuing research and development projects aim to improve occupant experience through networke...

Managing the lighting in secondary spaces such as stairwells, lobbies and service rooms based on occupancy can carve a big chunk out of overall energy use

Decisions throughout the life cycle of a building, from design through construction and commissioning to operation and demolition, require the involvement of multiple interested parties (e.g., architects, engineers, owners, occupants and facility managers). The performance of alternative designs and courses of action must be assessed with respect t...

The California Lighting Technology Center (CLTC) at the University of California, Davis, has implemented a successful Demonstration Program to help emerging, energy-efficient lighting technologies and gain a foothold in the mainstream marketplace. Bi-level parking garage luminaries integrate intelligent controls with bi-level electronic drivers or...

Extensive researchers efforts have played a key role in enabling high dynamic range (HDR) imaging to be used in several consumer electronics products. Some of these consumer electronics include cameras, mobile phones, and the latest version of the iPhone. The HDR technology has been integrated in these devices to provide better lighting experience....

Abstract This paper is about ,research and development,efforts ,on the ,use ,of information,technologies ,to assist ,in building,design ,decisions. Theoretical models,of the ,design and decision-making processes are described along ,with their implementation,for the development ,of the Building Design Advisor (BDA), a software environment,designed...

The research has been performed at the California Lighting Technology Center (CLTC) in order to achieve required energy performance and develop a technology-neutral Super Lamp specification for replacement of incandescent technologies in the residential sector. The CLTC specification considered several factors that included color, size, run-up time...

Daylight harvesting is a technique to save energy as it can reduce the electric lighting during the daylight for a commercial and industrial buildings. Daylight harvesting can help to reduce the peak electricity demand during the peak demand. Architectural and interior designs of a building can provide effective and efficient lighting over differen...

The unreliability of photosensor-based lighting controls continues to be a significant market barrier that prevents widespread acceptance of daylight dimming controls in commercial buildings. Energy savings from the use of daylighting in commercial buildings is best realized through the installation of reliable photoelectric lighting controls that...

Design studios and building science courses have been conducted independent of each other, mainly due to a lack of tools that allow quick and easy consideration of building science criteria, such as comfort and energy requirements, during the design process. Existing tools are not user-friendly and their use requires significant effort in gaining f...

To make decisions, building designers need to predict and assess the performance of their ideas with respect to various criteria, such as comfort, esthetics, energy, environmental impact, economics, etc. Performance prediction with respect to environmental impact requires complicated models and massive computations, which are usually possible only...

In this paper, we describe the product modeling techniques that we use for the development of a computer-aided decision-making tool for the building industry. We start with an introduction to modeling and a brief description of the goals and scope of the project, and follow with an extensive presentation and discussion of the modeling techniques em...

The use of daylight for the illumination of building interiors has the potential to enhance the quality of the environment while providing opportunities to save energy by replacing or supplementing electric lighting. Moreover, it has the potential to reduce heating and cooling loads, which offer additional energy saving opportunities as well as red...

The Building Design Advisor (BDA) is a software environment that supports the integrated use of multiple analysis and visualization tools throughout the building design process, from the initial, conceptual and schematic phases to the detailed specification of building components and systems. Based on a comprehensive design theory, the BDA uses an...

According to the contractual agreement, BTP would develop a computer model of the POC holographic structures and then simulate the performance of alternative designs using the RADIANCE lighting and rendering computer program [Ward 1990]. The RADIANCE model would then be used to evaluate the daylight performance of alternative designs of holographic...

The Building Design Advisor (BDA) is a software environment that supports the integrated use of multiple analysis and visualization tools throughout the building design process, from the initial, schematic design phases to the detailed specification of building components and systems. Based on a comprehensive design theory, the BDA uses an object-o...

The paper presents the results of a study investigating the energy performance of electrochromic windows under a variety of state-switching control strategies. We used the DOE-2.1E energy simulation program to analyze the annual cooling, lighting, and total electricity use and peak demand as a function of glazing type, size, and electrochromic cont...

The light diffraction properties of holographic diffractive structures present an opportunity to improve the daylight performance in side-lit office spaces by redirecting and reflecting sunlight off the ceiling, providing adequate daylight illumination up to 30 ft (9.14 m) from the window wall. Prior studies of prototypical holographic glazings, in...

We describe the integrated development of PowerDOE, a new version of the DOE-2 building energy analysis program, and the Building Design Advisor (BDA), a multimedia-based design tool that assists building designers with the concurrent consideration of multiple design solutions with respect to multiple design criteria. PowerDOE has a windows-based G...

Most utility demand-side management (DSM) programs are designed to capture savings by substituting more efficient building components for less efficient products;for example, replace magnetic ballasts with electronic ballasts. Much larger savings can be captured at lower cost if a systems perspective is applied to the problem of capturing demand-si...

A new, comprehensive design theory is presented, applicable to all design domains such as engineering and industrial design, architecture, city and regional planning, and, in general, any goal-oriented activity that involves decision making. The design process is analyzed into fundamental activities that are characterized with respect to the nature...

A new method to simulate the daylight performance of fenestration systems and spaces is presented. This new method, named IDC (Integration of Directional Coefficients), allows the simulation of the daylight performance of fenestration systems and spaces of arbitrary complexity, under any sun, sky, and ground conditions. The IDC method is based on t...

We report on the simulation of the energy performance of prototype holographic glazings in commercial office buildings in a California climate. These prototype glazings, installed above conventional side windows, are designed to diffract the transmitted solar radiation and reflect it off the ceiling, providing adequate daylight illumination for typ...

We present a representative review of existing, emerging, and future technology options in each of five hardware and systems areas in envelope and lighting technologies: lighting systems, glazing systems, shading systems, daylighting optical systems, and dynamic curtain wall systems. The term technology is used here to describe any design choice fo...

We present a representative review of existing, emerging, and future technology options in each of five hardware and systems areas in envelope and lighting technologies: lighting systems, glazing systems, shading systems, daylighting optical systems, and dynamic curtain wall systems. The term technology is used here to describe any design choice fo...

We present a representative review of existing, emerging, and future technology options in each of five hardware and systems areas in envelope and lighting technologies: lighting systems, glazing systems, shading systems, daylighting optical systems, and dynamic curtain wall systems. The term technology is used here to describe any design choice fo...

We present a representative review of existing, emerging, and future technology options in each of five hardware and systems areas in envelope and lighting technologies: lighting systems, glazing systems, shading systems, daylighting optical systems, and dynamic curtain wall systems. The term technology is used here to describe any design choice fo...

We present a representative review of existing, emerging, and future technology options in each of five hardware and systems areas in envelope and lighting technologies: lighting systems, glazing systems, shading systems, daylighting optical systems, and dynamic curtain wall systems. The term technology is used here to describe any design choice fo...

Continuously decreasing cost has brought computers into most architectural and engineering offices, most commonly for activities such as drafting, accounting and word processing. Computers are used less often to predict the performance of design solutions. However, most performance simulation software packages are simplified versions of main-frame...

For the purposes of determining their luminous performance, fenestration systems can be considered as luminaires of varying candlepower distribution. In this way, daylighting and electric lighting analyses can be performed simultaneously, in a consistent way. An approach to determine the transmitted distribution through fenestration systems due to...

A model of the design process and related knowledge and expertise is applied to develop an advanced, computer-based, Building Design Support Environment (BDSE). The BDSE will support building design from the initial schematic phases, through working drawings and specifications, to a building's construction, occupancy, and use. The BDSE will consist...

Accurate determination of the luminous and thermal performance of fenestration systems that incorporate optically complex components requires detailed knowledge of their radiant behavior. We describe a large scanning radiometer used to measure the bidirectional transmittance and reflectance of fenestration systems and components. We present example...

A large scanning radiometer for measuring the bidirectional transmittance and reflectance of fenestration systems and components is described. Examples of measured data obtained for simple non-specular samples using the radiometer are presented. A method of obtaining the overall bidirectional properties of systems by calculation from scanning radio...

A review of current daylighting design tools indicates that over 30 tools are now available, including nomographs, protractors, overlays, and programs for micro-, mini-, and mainframe computers. Computer-based tools allow testing and analyzing of more design alternatives under a wider variety of conditions than was previously practical with slower...

When hourly energy simulation models are used to predict the performance of multi-zone buildings, they may be required to perform more than 2,000 daylight analyses in a single simulation. The traditional approach is to use a very fast computational model, which of necessity must be a very simple model. Coefficient of utilization models have been wi...

The bidirectional solar-optical properties of a fenestration system are necessary to accurately determine its luminous and thermal performance. Bidirectional transmittance and reflectance can be determined experimentally for fenestration systems of arbitrary complexity using a scanning radiometer, after which the total directional absorptance can b...

Traditional computational models predict daylight illuminance in a space by dividing window surfaces into discrete areas and then calculating the apparent luminance of each window element by multiplying the luminance of the natural light source in a given viewing direction by the window transmittance in that direction. This approach works well for...

Using daylighting in commercial buildings may significantly reduce electric lighting requirements if appropriate photoelectric controls are used to adjust the electric lighting output according to the available daylight. Prior analysis and results from monitored buildings and scale-model measurements suggest that the selection, placement, and insta...

A key impediment to improving the energy efficiency and reducing the environmental impact of buildings is the complexity and cost of managing information over the life cycle of a building. A surprisingly large fraction of the total cost of buildings is embodied in the decision making and information management process due to the structure of the bu...

Lighting design involves the consideration of multiple performance criteria, from the earliest stages of conceptual design, through various stages of controls and operation in a project's life cycle. These criteria include: (1) the quantitative analysis of illuminance and luminance distribution due to daylighting and electric lighting; (2) qualitat...

Many building simulation computer programs, originally developed on mainframe computers for research purposes, can now run on the powerful workstation and personal computers that are available to most architectural and engineering firms. Major efforts have been underway during the last decade to compile these programs on personal computers and make...

In this paper we address the issue of building data schema evolution in integrated simulation environments, as seen from the perspective of incorporating LCA tools within these environments. First we describe the key features of an integrated simulation environment designed for expandability, focusing on (a) the mechanism for the expansion of the i...

We describe LBL's involvement with multimedia concepts by discussing several modules of an advanced computer-based building envelope design tool. The qualitative and quantitative aspects of the building design process are accommodated within the same design tool which uses object-oriented programming procedures. This computer-based concept utilizes...

The design of energy-efficient buildings can be aided by intelligent computer tools that can evaluate design solutions and make recommendations for improving the buildings` energy performance. Such tools can be very productive when they are integrated with existing computer-aided design technology. Pacific Northwest Laboratory, in collaboration wit...

We present results from the first phase of a project to develop a fenestration performance design tool to be used by builders, designers, architects, utility auditors, etc. In phase 1 we defined the design tool concept and the experimental and analytical methodologies required to achieve the project goal. We defined five fenestration performance in...

This paper documents an approach for evaluating the comfort impacts associated with varying fenestration system parameters primarily under the influence of direct solar radiation. The authors present a method of evaluation in which it was shown that an annual comfort index could be determined by knowing the fenestration system solar heat gain coeff...

The need for proper consideration of energy-related performance aspects during building design has been identified since the energy crises of the 1970s. However, energy performance is still considered in a very small fraction of building projects, mainly because proper consideration is very expensive. It requires the use of computational software t...

Energy savings from the use of daylighting in commercial buildings are realized through implementation of photoelectric lighting controls that dim electric lights when sufficient daylight is available to provide adequate workplane illumination. The dimming level of electric lighting is based on the signal of a photosensor. Current simulation approa...

A three-step method has been developed to automate the selection of fenestration systems based on specific daylighting performance goals. This paper contains a brief description of the complete method, focusing mostly on the use of the Radiance software for the required lighting computations.

This paper is about a web-based ?virtual lighting simulator? that is intended to allow architects andlighting designers to quickly assess the effect of key parameters on the daylighting and lightingperformance in various space types. The virtual lighting simulator consists of a web-based interfacethat allows navigation through a large database of i...

The objective of this paper is to provide a conceptual framework that facilitates the development of integrated software environments that address the data and process needs of all building-related disciplines through the whole buil ding life cycle. The conceptual framework is based on a comprehensive analysis of the data and processes involved in...

The use of daylight for the illumination of building interiors has the potential to enhance the quality of the environment while providing opportunities to save energy by replacing or supplementing electric lighting. Moreover, it has the potential to reduce heating and cooling loads, which offer additional energy saving opportunities, as well as re...

An attempt to determine how computers can be used to assist designers resulted in the development of a design theory, according to which design is 'feeling and thinking while acting.' Design is theorized as living through one's imagination, however being continuously affected by real life itself. The design process is decomposed into elementary act...

Design studios and building science courses have been conducted independent of each other, mainly due to a lack of tools that allow quick and easy consideration of building science criteria, such as comfort and energy requirements, during the design process. Existing tools are not user-friendly and their use requires significant effort in gaining f...