Museum Lighting - an holistic approach

Among the environmental parameters that effect exhibited artifacts, light is the most complex and the only essential for the observer as to appreciate the artifacts, thus being one of the most critical variables of art exposure. Research on strategies for energy saving and the renovation of light destined to Heritage is examined by daylight admission and Light-Emitting Diode (LED) technology. The extended review of the literature presented below, over museum lighting, evidenced the parallel advance of lighting principles with lighting design, concerning what determines visual quality and perception. Lighting quality is an interdisciplinaryfield of research affecting human activity and under a requested task, visual performance, while at the same time improving well-being. In this sense, the role of the lighting designer is to match and rank human needs with economic and environmental aspects as to architectural principles and to translate the results into a feasible design and an efficient installation. Quality factors for art exposure, involving color fidelity and damage, along with visual perception necessitate of useful metrics through established criteria. The challenge for the museum for a holistic design of natural and artificial light is still missing of substantial metrics, even though recent findings provide some insight on the workflow to establish. Luminance-based design metrics and contrast criteria are used in this study as key strategies for museum lighting, combining comfort and viewing fine arts through advanced computer rendering. The exploration of the transition inside a daylit gallery where moving in the museum environment offers an experience for a series of adaptation changes through photopic, mesopic and dark-adapted scotopic function, along with change on the sensitivity of the spectrum. The luminance appearance and the transition adaptation in the museum field lack of research examination; the relationship of prescriptive requirements and luminance- based design has been explored initially in the field of road lighting, where the relative visual performance has been evidenced to be in the center of the CIE standard for tunnel lighting. Daylight simulation via climate-based modeling, introducing daylight filters as solar shading devices, has been proposed as the object of experimental research, connecting light “filtering” with luminance; this workflow could be applied in several fields of research considering museum environment and give responses in the preservation of artwork involving daylight. The subject of this thesis is the proposal of a ‘trama’ surface installed on windows to reduce and control daylight, studying how energy and conservation targets can be achieved. New light sources and smart control systems will integrate to a holistic approach for museum lighting design

Urban lighting project for a small town: comparing citizens and authority benefits

The smart and resilient city evolves by slow procedures of mutation without radical changes, increasing the livability of its territory. The value of the city center in a Smart City can increase through urban lighting systems: its elements on the territory can collect and convey data to increase services to city users; the electrical system becomes the so-called Smart Grid. This paper presents a study of smart lighting for a small town, a touristic location inside a nature reserve on the Italian coast. Three different approaches have been proposed, from minimal to more invasive interventions, and their effect on the territory has been investigated. Based on street typology and its surroundings, the work analyzes the opportunity to introduce smart and useful services for the citizens starting from a retrofitting intervention. Smart city capabilities are examined, showing how it is possible to provide new services to the cities through ICT (Information and Communication Technology) without deep changes and simplifying the control of basic city functions. The results evidence an important impact on annual energy costs, suggesting smart grid planning not only for metropolis applications, but also in smaller towns, such as the examined one

Study of a daylight 'filter' zone in tunnels

In tunnels high energy consumption is required for guarantying the visual adaptation to the light contrast between daylight and tunnel luminance. The opportunity to graduate daylight in the threshold zone could create an area of adaptation of the human eye to the tunnel' s interior luminance, reducing consumption. In this paper a daylight “filter” structure, called pre-tunnel, is placed before the tunnel's portal, to investigate how a gradual reduction of luminance maintaining uniformity could be achieved; the structure presents very small circular holes on the ceiling giving access to natural light. A scale model has been constructed to test the effect of different diameters of holes on luminance and to evaluate the reduction of the lighting percentage. Results show the ability of this solution to have a potential control daylight management at the entrance of the tunnel

Study for optimizing the daylight 'filter' in a pre-tunnel structure

The elevated lighting demand in tunnel's portal zone to guarantee drivers eye adaptation to the internal luminance has been the subject of previous studies exploring the opportunity to gradually introduce daylight in the threshold zone and thus reduce consumption. A 1:10 scale model of this adaptation zone, called daylight 'filter' structure, has been constructed to investigate uniformity and luminance reduction under panels with different percentages of holed ceiling surface. The trend of the luminance curve compared to CIE curve of luminance led to the optimization of panels' position along the tunnel. Results confirmed the possibility of implementing drivers' vision introducing daylight through the 'filter' structure

Dynamic Lighting For Space Habitats

Studies about sleep deprivation in Space suggest the desynchronization of astronauts' circadian rhythm during the mission. This alteration could be caused by the absence of natural light variation in Space, together with low illuminance levels existing within the habitat. The paper proposes a new dynamic lighting approach suited for Space habitats reproducing Earth daylight variation by means of electrical light sources. In a daily schedule, the artificial lighting variation from 7 a.m. to 11 p.m. was planned according to previous studies about melatonin secretion and physiological parameters variation in human body. Variations of illuminance (E) level and Correlated Colour Temperature (CCT) are obtained using the new LED technology, a light source suitable for Space applications. Results obtained suggest that the proposed scheduled lighting scenarios produce the proper conditions for astronauts' circadian rhythm regulation and cognitive performance