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In 2020, an international project on residential lighting started and was implemented in four countries (Poland, Sweden, UK and Turkey). This article presents the results of a survey carried out in Poland, in the winter term between November 2020 and January 2021. A total of 125 Polish residents (59 women, 65 men, one person did not wish to specify gender) participated in the survey. A variety of data was collected on the respondents and their assessments as well as on their satisfaction with day- and artificial lighting in residential living spaces. The results from questionnaires were analyzed with STATISTICA 13.3. Descriptive statistics and Spearman rank order correlations were adopted to identify the light-related aspects, lighting patterns, and respondents’ perception of day- and artificial lighting conditions in living areas. The results revealed that satisfaction with daylighting in the living area, both in summer and winter, was significantly correlated with daylighting level, daylighting uniformity, sunlight exposure and view-out. The results also revealed that satisfaction with artificial lighting was significantly correlated with artificial lighting level, artificial lighting uniformity and color rendering. The results provide valuable information on lighting and factors that influence the luminous environment in residential living spaces.

This paper is related to light pollution and the energy efficiency of outdoor amenity lighting. It concerns the standard design assessment parameters of light pollution, the Upward Light Ratio (ULR) and Upward Flux Ratio (UFR), and the classic energy efficiency parameter—Normalized Power Density (NPD). The motivation for this research was the observation of certain inaccuracies related to the applicability and interpretation of these parameters in practice and the lack of connection between parameters of light pollution and energy efficiency. The multi-variant computer simulations of the exemplary large-area parking lot lighting system were conducted. Over four hundred cases were carefully analyzed. Individual cases differ in the shape of the task area, luminaire arrangements, mounting height, luminous intensity distribution, aiming, and maintenance factor. The results confirmed that the criteria values of ULR and UFR are often overestimated for modern luminaires, which emit luminous flux emitted only downwards. In this case, the ULR and UFR values do not exceed the criteria values for even zones with lower ambient brightness. Thus, lighting solutions with much lower energy efficiency easily meet the requirements of these parameters. This situation is not rational. So, it is crucial to make the criteria of ULR and UFR much more stringent in all environmental zones. Moreover, the research confirms a strong positive linear correlation between UFR and NPD (0.92, p < 0.001), which means that light pollution can be reduced by ensuring an appropriate level of energy efficiency. It is a great help in designing sustainable outdoor amenity lighting.

The current lighting solutions, both in terms of design process and later implementation, are becoming more and more intelligent. It mainly arises from higher opportunities to use information technology (IT) processes for these purposes. Designs cover many aspects, from physiological to including technical. The paper describes the problems faced by any designers while creating, evaluating them, and presenting the final results of their work in a visualisation form. Development of virtual reality (VR) technology and augmented reality, which is now taking place before our eyes, makes us inclined to think how to use this reality in lighting technology. The article presents some examples of applying VR technology in various types of smart lighting designs, for interiors and outdoor objects. The performed computer simulations are compared to reality. Some surveys, in terms of visualization rendering, were carried out. In the article, the current capabilities and main limitations of virtual reality of lighting are discussed, as well as what can be expected in the future. The luminance analysis of the virtual reality display is carried out, which shows that this equipment can be used in lighting technology after the appropriate calibration. Moreover, an innovative lighting design system based on virtual reality is presented.

In the era of recognising the adverse effects of our activities on the climate, more and more attention is being paid to designing sustainable solutions. The assumptions during such sustainable designs often do not fulfil the user’s needs and comfort. Therefore, we frequently encounter the discrepancies concerning higher energy consumption and user’s modifications in the building systems compared to the design and building use stages. To mitigate these problems in the context of interior lighting design, the authors innovatively researched the lighting preferences of a selected group of respondents based on their personality traits. The Gallup CliftonStrengths assessment tool was used for this research. The research was conducted using an online survey of 101 women from Poland with an average age of 42. The received lighting preferences were analysed using the descriptive statistics and the Kruskal–Wallis ANOVA test by Ranks. Some individuals exhibited preferences for electric lighting parameters that deviate from those recommended by the standards and current technical knowledge. Such preferences can sometimes lead to lower illuminances, maintaining comfort and reducing energy consumption. The knowledge of user’s preferences can reduce the discrepancies between the sustainable design and use stages as users’ interference in device operation will be minimised by meeting their needs, thus achieving sustainable goals.

This article describes a system for designing floodlighting of objects using computer graphics. Contrary to the currently used visualisation tools, the developed computer application is based on the daytime photography of the object and not on its three-dimensional geometric model. The advantage of the system is the high photorealism of the simulation, with no need to create a collage of visualisation with photography. The designer uses the photometric data of luminaires, and their photometric and colourimetric parameters are defined. With the system it is possible to perform a precise lighting analysis—the distribution of illuminance and luminance—both for the entire facility and in any plane or point. The system also analyses the total installed power of a given design solution. The system application is presented as an example in the form of a case study. This example shows the features of the system and further expected directions of development.

Replacing inefficient lighting with energy-efficient alternatives is a proven way to reduce urban energy use, yet evaluating such policies remains challenging. For example, in 2013, New York City (NYC) initiated a program to replace 250,000 high-pressure sodium (HPS) streetlights with light-emitting diodes (LEDs) by 2017, but no subsequent evaluation was published. Here, we employ ground-based hyperspectral imaging (HSI; 0.4–1.0 microns, ∼850 bands) observations from the “Urban Observatory” (UO), obtained in 2013 and 2018, to quantitatively characterize this technological transition. Following co-registration, artifact removal, and source identification, we classified individual light source technologies using both a maximum correlation approach with spectral templates of known lighting types and a one-dimensional Convolutional Neural Network (1D-CNN) trained on 1321 manually labeled spectra, achieving an average precision of ∼92% for the 2013 data and ∼94% for the 2018 data across technology classes. Scene-level mixture modeling indicates a reduction in the HPS-to-LED brightness ratio from 1.15 (2013) to 0.27 (2018), demonstrating the capability of longitudinal HSI for evaluating urban lighting policy outcomes.

The paper presents the opportunities to apply computer graphics in an object floodlighting design process and in an analysis of object illumination. The course of object floodlighting design has been defined based on a virtual three-dimensional geometric model. The problems related to carrying out the analysis of lighting, calculating the average illuminance, luminance levels and determining the illuminated object surface area are also described. These parameters are directly tied with the calculations of the Floodlighting Utilisation Factor, and therefore, with the energy efficiency of the design as well as the aspects of light pollution of the natural environment. The paper shows how high an impact of the geometric model of the object has on the accuracy of photometric calculations. Very often the model contains the components that should not be taken into account in the photometric calculations. The research on what influence the purity of the geometric mesh of the illuminated object has on the obtained results is presented. It shows that the errors can be significant, but it is possible to optimise the 3D object model appropriately in order to receive the precise results. For the example object presented in this paper, removing the planes that do not constitute its external surface has caused a two-fold increase in the average illuminance and average luminance. This is dangerous because a designer who wants to achieve a specific average luminance level in their design without optimizing the model will obtain the luminance values that will actually be much higher.

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.

This paper presents an attempt at a unified approach for the assessment of outdoor lighting solutions at the design stage. First of all, the lighting criteria for different types of outdoor lighting installations have been carefully described. Despite the differences in criteria, it is possible to find a common ground for the assessment of lighting solutions at the design stage. This is based on the need for the assessment of lighting solutions to be included in the requirements for the luminous environment, light pollution, and energy efficiency. The review and analysis of the standards and reports allows an experimental procedure to be created, the main aim of which is to find the best and most sustainable lighting solution for any outdoor situation. The procedure was tested by the example of an analysis of parking lot lighting solutions. In the case analyzed, 120 solutions were considered. It appeared that, in only 65 cases were the requirements referring to both lighting condition and light pollution met. Finally, based on the lighting energy efficiency assessment, ten solutions were selected as the most suitable. Furthermore, only one solution out of the ten was the most beneficial, taking into account the extra criterion of basic economic cost. The case study confirms that the assessment procedure allows the most beneficial solution to be selected, taking into account the luminous environment, as well as light pollution and energy efficiency criteria. The proposed multi-criteria assessment procedure may be used as a valuable tool by lighting designers to select the most beneficial solution in order to meet the needs of safety, visual efficiency, and comfort, as well as taking into account light pollution and energy efficiency restrictions.

Energy efficient lights, such as fluorescent lamps (FLs) and light-emitting diode (LED) lamps, can greatly help energy saving, which is critical for achieving carbon neutrality in the building sector. Yttrium, europium, and terbium are three essential rare earth elements (REEs) for energy efficient lighting. However, due to the ongoing lighting technology transition from FLs to LED lamps, the demands for yttrium, europium, and terbium have decreased significantly. It resulted in oversupplies of these three REEs in the lighting sector, indicating an economically and environmentally unsustainable supply chain. This study aims to estimate the supply and demand dynamics of yttrium, europium, and terbium in China from 2021 to 2060 under China’s carbon neutrality target by applying a dynamic-material-flow-analysis framework. Key flows and stocks along their life cycles are examined. Results show that the annual demands for yttrium, europium, and terbium in China’s lighting sector will decrease by 87%–100% from 2021 to 2060 under two demand scenarios. Driven by the demands for other co-produced critical REEs, the overall growing REEs supply will result in high surplus risks of yttrium and europium. Meanwhile, terbium deficit risk deserves more attentions due to its demand growth in other fields. Such surpluses of these three REEs in 2060 under six combined demand and supply scenarios are estimated to reach between 71 727 tonnes and 274 869 tonnes for yttrium, 530 tonnes and 1712 tonnes for europium, and −1360 tonnes (i.e. deficit) and 540 tonnes for terbium. Recycling activities of major co-produced REEs, such as neodymium, and the export expansion of surplus products can effectively mitigate such surplus risks. Finally, policy recommendations are proposed to improve the overall REEs efficiency by addressing the supply–demand imbalance and mitigating corresponding environmental impacts.