The paper presents the authors’ concept of an adaptive road lighting that is concurrent with vehicles moving on roads. The lighting system is based on luminaires with light emitting diodes. The authors describe the operation of the adaptive road lighting system and point out benefits and limitations of the solution. The theoretical considerations are supported by an analysis of the installed and working system that was implemented at Bożeny street in Poznan, Poland. The system was also evaluated by the residents living near the street.
The article proposes a method for measuring discomfort glare which uses numerical description of the phenomenon in the form of a digital luminance distribution map recorded on a CCD array. Essential procedures for determining partial quantities which are necessary for calculation of UGR index are discussed in detail, along with techniques for measuring position index and size of light sources, with regard to the parameters of the registering system and coordinates of the images of the sources on the array.
Designing, optimizing and analyzing optical systems as part of the implementation process into production of modern luminaires require using advanced simulation and computational methods. The progressive miniaturization of LED (light emitting diode) chips and growth in maximum luminance values, achieving up to 108 cd/m2, require constructing very accurate geometries of reflector and lens systems producing complex luminous intensity distributions while reducing discomfort glare levels. Currently, the design process cannot function without advanced simulation methods. Today’s simulation methods in the lighting technology offer very good results as far as relatively large conventional light sources such as halogen lamps, metal halide lamps and high pressure sodium lamps are concerned. Unfortunately, they often fail in the case of chip-on-board LED light sources whose luminous surface dimensions are increasingly often contained inside a cube of the side length below 1mm. With the high sensitivity of such small chips and lenses with dimensions ranging from a just a few to between 10 and 20 mm, which is presented in this paper, modern luminance distribution measurement methods, luminance modelling and ray tracing methods should be used to minimize any errors arising from incorrectly projecting the design in the final physical model. Also, very importantly, focus should be directed towards reducing a chance of making a mistake while collimating the position of the light source inside the optical system. The paper presents a novel simulation calculation method enriched with an analysis of optical system sensitivity to a light source position. The results of simulation calculations are compared with the results of laboratory measurements for corresponding systems.
Lighting technologies developed significantly in the last decade. New LED light sources, dedicated luminaires and improved lighting control techniques gave rise to new possibilities in improving energy efficiency of lighting solutions. The article is an overview of interior, road and exterior architectural object lighting design strategies. It also presents design considerations that directly impact lighting conditions and energy efficiency. Practical examples of the application of basic design strategies, accompanied by the obtained energy results, are also depicted. Issues discussed in the article may be useful in researching and designing interior and road lighting, as well as floodlighting. They can also be useful in planning and implementing strategies aimed at improving lighting conditions and energy efficiency of lighting solutions.
The article presents how multi-layered urban lighting projects fit into the programs of integrated activities to improve the living conditions of the local community, the surrounding space, and its economic relations. The role of the electric lighting in revealing the night image of the city, its promotion and public spaces transformations offering new impressions to city residents is growing thanks to the use of the SSL technology. The authors focus on a role of outdoor lighting projects in urban regeneration within the selected urban areas. The paper describes how conscious shaping of lighting by analysing the goals and stages of the project can contribute to the improvement of quality in the processes of renewal of degraded urban areas.
General lighting is the most common way of illuminating interiors and the source of electricity consumption in buildings. This fact forces the search for lighting solutions effective both for people and the environment. In this study the impact of room and luminaire characteristics on general lighting conditions and energy efficiency in interiors is considered. In rooms of different sizes and reflectances, seventeen luminaire types with various light distributions were arranged in uniform layouts. The levels of average illuminance, uniformity and normalised power density related to two horizontal working planes were calculated. The impact of working plane reduction, room index and reflectances, lighting class and luminous intensity distribution of luminaire on the considered parameters was investigated. The use of the reduced working plane resulted in the increase in the average illuminance (7.7% on average), uniformity (33% on average) and normalised power density (23% on average). The impact of the room index and lighting class on the average illuminance and normalised power density was significant while the impact of the luminaire luminous intensity distribution and room reflectances was low. The normalised power density levels of the general electric lighting in interiors, with luminaire luminous efficacy of 100 lm/W, are in the following range: 1.08‒3.42 W/m² per 100 lx. Based on these results a normalised power density level of 2 W/m² per 100 lx is recommended for designing and assessing the new general electric lighting systems in buildings.
The paper puts forward and implements a method of designing and creating a modelling simulation environment for extensive and complete analysis of economical lighting on highways. From a general design viewpoint, the proposed solution explores the concept of a network description language (SMOL), which has been designed to describe the necessary network functions, mechanisms, and devices for the purpose of their computer simulation and verification. The presented results of the performed research confirm the usability of intelligent lighting on highways, both in the sense of the design concept and in the aspect of saving energy.
Lighting sources with a cold cathode are widely used in electronics. The lamps with a cold cathode are used primarily as sources of white light in optical scanners, digital indicators, display panels and signalling devices. In the paper the advantages of carbonaceous materials as emitters of cold electrons and the possibilities of using them to create a cathode in an electron lamp are discussed.
The development of technology and design of light management systems remains dynamic. Among all the benefits offered by these systems, the most valuable might definitely be the possibility of saving energy consumption. Knowing the value of energy savings is the key factor that users need to know before deciding to use a lighting management system (the type of light management system). For this purpose, it is useful to simulate the operation of the lighting control system, for example in the DIALux program. Such simulation helps evaluate potential savings in electricity consumption using the proposed lighting control system. In the DIALux program, it is possible to change the luminous flux value of luminaires. In such a case, it becomes possible to semi-simulate the light management system’s operation as we don’t receive actual information on reducing installed power of the lighting system during reduction of the luminous flux value of luminaires. This article shows what type of technical data are important to use for the DIALux program to properly and accurately simulate light management systems and to receive accurate data on energy saving. It also presents the results of photometrical and electric parameter measurements (Φ – luminous flux, P – power, PF – power factor, THDi – total harmonic distortion of current). The article discusses the power control characteristics obtained on the basis of these measurements and explores the source of differences between simulation of energy saving calculations and real measured energy savings. An existing lighting control system installed in an office reception area was used to compare calculations with the real value of energy consumption reduction. The impact of electronic power and control systems on electrical network parameters is also an important problem mentioned in this article. It also explores the effect of power regulation of LED luminaires and LED modules on the value of the power factor and total harmonic distortion (current) value (THDi).
In the paper, an effective way to design asymmetrical optics for a uniform vertical surface illumination was presented. Assessment of the obtained distribution of luminance (illuminance) on the illuminated surface is done almost at the same time as designing the optical system elements. Advantage of the final application of the presented method in 3D will be independence from the implementation of time-consuming simulations in order to verify the already designed optics. Understanding the method and its application is simple and intuitive. Observing the luminance distribution, created on the illuminated surface almost at the same time as its design, allows to see the effect of adding the next elements of the optical system on this distribution.
This article is focused on considerations based on experimental studies concerning changes of selected parameters of identical compact fluorescent lamps (CFLs) intended for use in buildings during their operation. The studies constituted a long-term experiment whose goal was an evaluation of selected operating parameters of the CFLs in terms of meeting the requirements set out in the specified regulations as well as the issue of marking the lamps with the energy efficiency class. The measurements were performed with the authors’ experimental setup consisting of original equipment designed and made especially for the purpose of the measurements. The studies covered registration of the luminous flux as well as selected electrical parameters such as active power, current and the power factor during the so-called “start-up time” and operation time equal to 100 h, 500 h, 1000 h, 2000 h, etc. with a 1000 h step. The studies were finished with the moment of natural burnout of the CFLs tested. The results showed that the biggest drawback of CFLs is lack of preservation of the required time to reach 60% of the stabilized luminous flux just after short time of lamp operation. Similarly when assessing the conformity of the parameters declared by the manufacturer that have been verified, it can be stated that they are true only at the initial stage of lamp operation.
This article is focused on considerations based on experimental studies concerning changes of selected parameters of identical compact fluorescent lamps (CFLs) intended for use in buildings during their operation. The studies constituted a long-term experiment whose goal was an evaluation of selected operating parameters of the CFLs in terms of meeting the requirements set out in the specified regulations as well as the issue of marking the lamps with the energy efficiency class. The measurements were performed with the authors’ experimental setup consisting of original equipment designed and made especially for the purpose of the measurements. The studies covered registration of the luminous flux as well as selected electrical parameters such as active power, current and the power factor during the so-called “start-up time” and operation time equal to 100 h, 500 h, 1000 h, 2000 h, etc. with a 1000 h step. The studies were finished with the moment of natural burnout of the CFLs tested. The results showed that the biggest drawback of CFLs is lack of preservation of the required time to reach 60% of the stabilized luminous flux just after short time of lamp operation. Similarly when assessing the conformity of the parameters declared by the manufacturer that have been verified, it can be stated that they are true only at the initial stage of lamp operation.