Potential Long-Term Global Environmental Implications of Efficient Light-Source Technologies

Summary Artificial lighting is a major source of electricity demand globally. As the demand for lighting services grows over the next 40 years, especially in developing countries, efficient light‐source technologies such as light‐emitting diodes (LEDs) can reduce the energy consumed for lighting services and therefore its environmental impacts. LED technologies in both residential and commercial/industrial applications are expected to see dramatic improvements in luminous efficacy over the coming decades, potentially leading to more environmentally benign lighting. A scenario‐based, integrated hybrid life cycle assessment quantifies and confirms the environmental benefits of deploying efficient light sources in all global regions through 2050, with electricity generation following the International Energy Agency's (IEA) BLUE Map scenario for limiting climate change to 2 degrees Celsius. Data used for previous assessments of light sources is updated and harmonized to reflect recent and expected future improvements in luminous efficacy and materials efficiency for LED lamps and luminaires. The aggregate life cycle greenhouse gas (GHG) emissions of global light provision can be reduced by more than a factor of 7 owing to decarbonization of electricity generation, increased adoption of efficient light sources, and future advances in LED technology. Estimates of the technological capability and market penetration of efficient light sources show that by 2050, a 2.5 to 2.9 times growth in the global demand for lighting services can be accommodated while still meeting IEA GHG mitigation goals and increasing metal depletion just 20% above 2010 estimates.