The Solid-State Lighting Program at the U.S. Department of Energy’s Office of Energy Efficiency & Renewable Energy (EERE) published a life-cycle analysis (LCA) looking at the environmental impact of producing and using LED lighting as compared to incandescent and compact fluorescent lamps. The report, titled Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products, Part 2: LED Manufacturing and Performance, is the second part of a larger DOE project to assess the life-cycle environmental impacts and resource costs of LED lighting products in relation to comparable traditional lighting technologies.
The study compared 60W incandescent lamps, 15W compact fluorescent lamps (CFL) and 12.5W LED lamps. It found that incandescent lamps have the highest environmental impact of all the lamps considered, primarily because of their low efficacy and the amount of energy required to produce light as a result. Energy needed to manufacture product replacements to span the longer rated life of an LED lamp or CFL is also a factor, the report said. Generating the higher amount of electric energy consumed per unit of light output causes substantial environmental impacts and results in the incandescent lamp being the most environmentally harmful across all the impact measures covered in the study.
The researchers from Pacific Northwest National Laboratory who conducted the study found compact fluorescent lamps (CFLs) are slightly more harmful than the 2012 integrally ballasted LED lamp across all criteria except one — hazardous waste landfill, where manufacturing the large aluminum heat sink used in the LED lamp causes the impacts to be slightly greater for the LED lamp than for the CFL.
Researchers also compared the three existing lamp technologies with the projected performance of LED lighting systems in 2017, taking into account several prospective improvements in LED manufacturing, performance and driver electronics. The 2017 LED systems, predictably, are expected to perform significantly better than all three existing technologies.
The report uses the conclusions of Part 1, Review of the Life-Cycle Energy Consumption of Incandescent, Compact Fluorescent, and LED Lamps, as a starting point to produce a more detailed and conservative assessment of the manufacturing process. That study found that the life-cycle energy consumption of LED lamps and CFLs are similar, and significantly more efficient than incandescents. The second part of the study looks at a wider range of environmental impacts than Part 1, covering 15 impact measures in four broad categories — resource impacts, air impacts, water impacts and soil impacts.
The report concludes that continued focus on efficacy targets, cost reduction and market acceptance is appropriate.
“The important finding from the LCA study is not minor relative differences between the LED lamp and the CFL, but the significant reduction in environmental impacts from replacing an incandescent lamp with a more efficient product. Reductions on the order of three to 10 times are possible across the indicators by transitioning the market to new, more efficacious light sources,” said the report’s summary.
The third part of the report, which will focus on disassembly and chemical testing of the lighting alternatives, is expected to be published in late 2012.