Promoting future sustainable utilization of rare earth elements for efficient lighting technologies

Abstract

Energy efficient lights, such as fluorescent lamps (FLs) and light-emitting diode lamps (LEDs), can greatly help achieve carbon neutrality in the building sector. Yttrium, europium, and terbium, three rare earth elements (REEs), are essential for energy efficient lighting. However, due to the ongoing lighting technology transition from FLs to LEDs, 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 forecast the supply and demand dynamics of yttrium, europium, and terbium in China from 2021 to 2060 under the carbon neutrality contexts by applying a dynamicmaterial-flow-analysis based 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 88%-100% from 2021 to 2060. Driven bythe demand for other co-produced critical REEs, the growing REEs supply will resultin high surplus risks of yttrium and europium. Meanwhile, terbium deficit risk needsattention due to its demand growth in other fields. Such surpluses of these three REEsin 2060 are estimated to reach between 71,762 tons and 274,869 tons for yttrium, 535tons and 1,712 tons for europium, and -1,360 tons (i.e., deficit) and 540 tons forterbium R. ecycling 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 from governance, technology, and economic instruments perspectives.