Apart from the visual effects, light can also affect the human non-visual system, which includes a wide range of functions such as hormone secretion, alertness, mood etc. The non-image forming effects occur because light affects melanopsin, a photosensitive protein present in the receptive domain of retinal ganglion cells. These cells are responsible for generating nerve impulses that regulate the secretion of two hormones, cortisol and melatonin. Low-wavelength light at 460-480 nm inhibits melatonin secretion and activates brain activity. Aim of this paper is to create a sustainable and human centric luminaire suitable for office installations that will regulate the biological rhythm of the occupants and has the minimum environmental impact. The luminaire’s light source emits variable spectrum, with a collated colour temperature varying between 2700K and 6500K. For a 500K step of colour temperature values, the appropriate human centric lighting metrics are calculated: Equivalent Melanopic Lux, Melanopic Daylight Equivalent Illuminance, Circadian Stimulus. The development of the human centric luminaire considers not only the metrics of human centric lighting but energy efficiency and visual comfort as well. Conclusively, the proposed luminaire can provide a holistic approach to lighting design so as to integrate both visual and non-visual effects and produce sustainable and environmentally friendly lighting.
In general, for the last 150 years, linear economy dominates the society. A model in which products are made from raw materials recovered from the environment, used, repaired, and finally disposed of in landfills. The environmental impact of the linear economy gave rise to the concept of the circular economy. This paper aims to provide a literature overview that presents ways that lighting products can participate in the circular economy, and define the role and effect that specific strategies have on the design, production, use and end-of-life of lighting products. In this new model of circular economy, lighting products participate with specific strategies that help reduce the waste that eventually leads to the environment and also to conserve natural resources. These strategies are R9=Recover, R8=Recycle, R7=Repurpose, R6=Remanufacture, R5=Refurbish, R4=Repair, R3=Reuse, R2=Reduce, R1=Rethink and R0=Refuse. In recent years, many manufacturing companies that design and manufacture lighting products in the initial design of their products now use circular economy strategies. Also, independent scholars, agree on the necessity of using circular economy, since its benefits can reduce the environmental impacts, energy, and emissions and finally to reduce or even eliminate the waste that eventually leads to the environment
Life Cycle Impact Assessment (LCIA) of lighting products is a methodology that analyses and evaluates environmental impacts throughout their total life cycle, from the extraction and processing of raw materials, design, construction, transportation, distribution, use, recycling and re-use of materials, and last their final disposal. According to the results of a large number of LCIAs, lighting products have a substantial environmental impact in multiple areas, as for example in primary energy, toxicological effects, the effect on global warming, the level of environmental acidification, etc. All of those impacts could result in more efficient products by enhancing the product design process (using Ecodesign). At the initial design stage of lighting products, the manufacturer should also take into consideration circular economy aspects at the End of Life stage (EoL) such as repair, reuse, remanufacturing, retrofitting, recycling, and upcycling and not only the energy savings from the use stage or the selection of raw materials. The scope of this paper is to collect and present an overview of all environmental impacts of LCIA analyses focusing at EoL stage of lighting products. Those impacts could be used as data input into a future model that determines which lighting products are more environmentally friendly.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.