A New York Times article by Eric A. Taub reports that a study conducted by the Siemens Corporate Technology Centre for Eco Innovations shows that LED lamps are essentially as energy efficient as compact fluorescents in the amount of energy needed to create, recycle and power a lamp. The study considered many factors, including the energy need to ship a lamp from a Chinese factory to a European installation.
Taub pointed out energy expended to create and dispose of an LED lamp that exceeds that for a comparable standard bulb negates any proclaimed energy efficiency.
A preliminary study, issued in March by Carnegie Mellon, indicated LED lamps were more energy efficient throughout their life, but the researchers pointed out that all aspects of the production process weren’t considered.
The Osram/Siemens (Siemens is the parent company of Osram) study used a 25,000-hour LED lamp life as a constant, comparing the energy needed throughout its life to that used for 25, 1,000-hour incandescents and 2.5, 10,000-hour compact fluorescents.
Osram expects those numbers to improve as LEDs become more energy efficient.
“Compound-semiconductor-optoelectronic fabrication facilities typically consume substantial energy to run and maintain,” explained ST’s “EDS Update” columnist Dr. Nisa Khan. “This can be compounded when yields of high-end LEDs are low, the problem otherwise known as the binning problem, particularly for high-brightness white LEDs.
“This study carried out by Osram/Siemens is encouraging and hopefully will point out where the cost and energy breakdowns are for a typical LED bulb comparable to a CFL. In the future, as LEDs become much more energy efficient and more easily reproducible, the energy consumption during production will decrease, and we can expect lower-cost LEDs in the market,” Khan said.
“CFLs have proved to be more energy and cost efficient compared to the current incandescent lamps,” Khan continued. “However, the biggest concern with CFLs appears to be the mercury content in them, posing a safety hazard in households. Manufacturers are continually improving several aspects of CFLs: lower mercury content, better recycling practices, warmer white color and dimmable features.”
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