Life cycle assessment of high-power white LEDs for indoor lighting in the context of Hong Kong

Abstract

The introduction of white light-emitting diodes (LEDs) is one of the key innovations that has revolutionized the lighting industry due to its multiple benefits. Despite their advantages, there is a gap in the environmental impact information of the recently developed high-power LED products within the whole lifecycle, which is a key step to achieve sustainable and green development. This life cycle assessment (LCA) is conducted by considering the cradle-to-grave system boundary. The functional units considered are a LED and compact fluorescent lamp (CFL) of 40 million lumen-hours (lm-h) used for indoor applications over an operating time of 20 000 h. In this study, the LCA was carried out using the SimaPro software and built-in ecoinvent database V2.2 with appropriate life cycle inventory data. The analysis results indicate that: (1) the LED-package has a dominant environmental impact followed by the LED driver while the housing and corrugated-board packaging materials showed the least negative effect to the ecosystem during the manufacturing phase. On the contrary, the CFL drivers are dominant followed by the light sources in the case of CFLs. From the lifecycle stages, the usage-phase showed a predominant environmental effect, mainly due to the energy consumption and sources of energy production. (2) A scenario analysis on the sources of electricity production revealed that prospective sources (70% natural gas, 25% nuclear and 5% pumped storage) of energy production lowered the environmental impact compared to the current electricity mix. These proposed electricity generation production sources provide a 61% reduction in the global warming potential in light sources for Hong Kong.