Life cycle assessment of spectrally tunable light engines

This paper presents the life cycle assessment (LCA) of fully spectrally tunable solid-state lighting (SSL) systems conceived to operate in two different application fields: artwork (museum lighting) and horticulture. The choice of these scenarios responds to the requirement of high-quality light with reduced energy consumption. Reductions from 30% up to 60% in the energy consumption throughout the SSL systems life cycle compared to conventional luminaires are expected in an average European scenario.

The main objective of this work is to identify the environmental performance of these light engines using LCA methodology with the aim of improving their design for optimal recyclability and minimal resource consumption. For this purpose, the study includes an extensive inventory analysis of components and materials used for the luminaire production. In order to underline the environmental benefits of our light-emitting diode (LED) modules, a comparative LCA analysis has been set. This analysis has been done by comparing the lighting performance of our LED modules and their respective equivalent conventional luminaires (halogen and high-pressure sodium luminaires) within the selected application fields (artwork and horticulture, respectively).

The study shows that for both application scenarios, the highest contribution of the LED engines to environmental performance corresponds to the use phase when European average electricity mix is applied. On the contrary, when applying a high renewable source share electricity mix, the production phase becomes more significant. For LED luminaires, almost all the environmental indicators are strongly affected by the presence of electronic parts. The comparison also reveals that LED lighting exhibits lower environmental values for those impact categories related to energy consumption, whereas the use of electronic components in LED fixtures makes the results for the abiotic depletion (elements) higher than those exhibited by conventional luminaires. A meticulous analysis of our artwork design reveals potential 25% reduction in the nominal power consumption through a subsequent optimization design thereby enhancing its environmental profile compared to halogen luminaires.

Spectrally tunable LED luminaires discussed in this study for the selected scenarios show lower environmental impacts compared to the selected conventional luminaires, above all when comparing the results due to their lower energy consumption in their use phase. Trade-off between smart capabilities of our light engines and the use of materials required to implement them (mostly electronic components) is mandatory during the design stage, in order to minimize the environmental impact of the production phase.