DOE Declares LED Most Environmentally Friendly Light Source

A new US Department of Energy (DOE) report finds that LED lamps have a significantly lower environmental impact than incandescent lighting and a slight environmental edge over compact fluorescent lamps (CFLs). The report, LED Manufacturing and Performance, compares these three technologies from the beginning to the end of their lifecycles—including manufacturing, operation, and disposal. The most comprehensive study of its kind for LED lamps, the new report goes beyond energy consumption to analyze the energy and environmental impacts of manufacturing, assembly, transport, operation, and disposal of these three lighting types, and is the first public report to consider the LED manufacturing process in depth.

DOE found today’s integrally ballasted LED lamp to be more environmentally friendly than CFL against all but one criterion: hazardous waste landfill. The manufacturing of the large aluminum heat sink used in the LED lamp causes the impacts to be slightly greater for the LED lamp than for the mercury-containing CFL.

The researchers projected the evolution of LED technology (anticipated improvements in LED manufacturing, performance and driver electronics) and predict that the impacts of the LED lamp in 2017 will be far lower than the CFL and the LED lamp of 2012. The most important finding is not the minor relative differences between CFL and LED technology, but instead the highly significant reduction in environmental impacts that will result from replacing an incandescent lamp today.

The report is the second part of a larger DOE project to assess the lifecycle environmental impacts and resource costs of LED lighting products in relation to comparable traditional lighting technologies. It uses the conclusions of Part 1, Review of the Life-Cycle Energy Consumption of Incandescent, Compact Fluorescent, and LED Lamps, to produce a more detailed and conservative assessment of manufacturing processes, taking into consideration a wider range of environmental impacts. The Part 1 report concluded that the lifecycle energy consumption of LED lamps and CFLs are similar at approximately 3,900 MJ per 20 million lumen-hours. Incandescent lamps consume significantly more energy (approximately 15,100 MJ per 20 million lumen-hours).

Key findings of Part 2:

  • Electricity consumption over an equivalent period of lighting service is far greater for the incandescent lamp, and is the dominant contributor to environmental impacts.
  • Because of its low efficacy, the incandescent lamp is the most environmentally harmful of the three lamp types considered, across all 15 impact measures.
  • The CFL is slightly more harmful than the 2012 LED lamp (today’s LED technology) on all impact measures except hazardous waste landfill, where the LED lamp’s large aluminum heat sink causes greater impact because of the energy and resources consumed in manufacturing it (which produces significant waste disposed of in landfills).
  • The best-performing light source is the LED lamp projected for 2017, whose prospective impacts are expected to be about 50 percent lower than the 2012 LED lamp and 70 percent lower than the CFL.

Visit www1.eere.energy.gov/buildings/ssl/tech_reports.html to download the full reports or summaries; both Part 1 and Part 2.