DOE Study Confirms LEDs Most 'Environmentally Friendly' Lighting

LED lamps have a slight environmental edge over compact fluorescent lamps and a significantly lower environmental impact than incandescent lighting over the lifetime of the products, according to a Department of Energy report.

The report, LED Manufacturing and Performance, is the second part of a DOE project to assess the life-cycle environmental and resource costs in the manufacturing, transport, use and disposal of LED lighting products.

Part 1, published in February, concluded that the life cycle energy consumption of LEDs and CFLs are similar — about 3,900 MJ per 20 million lumen-hours. LEDs consume 12.5 watts of electricity to produce about the same amount of light as a 15-watt compact fluorescent lamp or a 60-watt incandescent.

The new report finds that the energy these lighting products consume during operation makes up the majority of their environmental impact, compared to the energy consumed in manufacturing and transportation.

The study compared the environmental impacts associated with a CFL, an incandescent lamp, a 2012 Philips Endural LED and a 2017 LED (anticipating improvements in manufacturing, performance and driver electronics), by preparing “spider graphs” (pictured), with the impact of each lamp plotted on the graph. Lights with the least impact have their circle close to the center and lights with the greatest impact will be on the outer edges of the web.

Other key findings:

• CFLs have a slightly higher environmental impact than 2012 LED lamps on all measures except their contribution to landfills. The aluminum contained in an LED lamp’s large aluminum heat sink causes a greater impact on landfills because of the energy and resources consumed in manufacturing.
• The report projects that in five years, the environmental impacts of LEDs will be significantly lower than today’s LED products, based on expected near-term improvements in LED technology.
• As the market transitions from incandescent sources to energy-saving light sources that save consumers and businesses money, LEDs and CFLs are expected to achieve substantial reductions in the environmental impacts assessed —  from 1/3 to 1/10 current levels.

The study also makes recommendations for future work, suggesting DOE work with manufacturers to reduce the size of LEDs' aluminum heat sinks and/or find alternative materials, and work with manufacturers to meet DOE targets for efficiency.

The last part of the project, Part 3, will test LEDs for disposal thresholds.