It seems that new technologies almost always attract criticism, sometimes well founded but often less so. So it has been with efforts to transition society from conventional incandescent lightbulbs to compact fluroescents and now to light-emitting diodes. With each of the new technologies there have been voices raised challenging the claims of environmental benefits.

Now a detailed study by the Pacific Northwest National Laboratory of the United States Department of Energy has provided what we hope is enough data to put the concerns to rest or at least to put the debate on a more sound scientific footing.

The reports, prepared for  the Solid-State Lighting Program of DOE’s Office of Energy Efficiency & Renewable Energy, have used Life Cycle Analysis tools to rigorously compare the three types of lighting. The lightbulbs have been compared on fifteen LCA parameters, including:

•  hazardous waste
• radioactive waste
• non-hazardous waste
• abiotic resource depletion
• terrestrial ecotoxicity
• ecosystem damage
• land use
• global warming
• acidification
• photochemical oxidation
• stratospheric ozone depletion
• human toxicity
• freshwater aquatic toxicity
• marine aquatic toxicity
• eutrophication

On all but one parameter, LED lightbulbs were found to be environmentally better than compact fluorescent lightbulbs.  Both LEDs and CFLs were significantly better than incandescent lightbulbs in all parameters. The one area where LEDs are slightly worse than CFLs is generation of hazardous waste. LED lightbulbs use an aluminum heatsink and manufacture of that aluminum adds to the hazardous waste element of their lifecycle. The researchers expect that this element will decline as new technology LEDs are introduced over the next few years. The new technology LEDs will produce less heat and therefore will require a smaller heatsink, the production of which generates less hazardous waste. However, even with the aluminum heatsink issue being taken into account, the data are pretty conclusive that LEDs are, from an environmental perspective, the best type of lightbulb currently available.

With CFLs now being shown quite clearly to be environmentally better than the incandescent bulb, GallonDaily hopes that both the federal and Ontario governments will return to their commitment to phase out traditional incandescent bulbs. This should be one of the easiest ways to pick up an approximately 5% reduction in electricity use with very little if any economic cost and a significant number of environmental co-benefits.

The Department of Energy LCA reports on lightbulbs, along with a press release, are available at http://www.pnnl.gov/news/release.aspx?id=940